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/*
* Copyright (C) 2013-2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_INCLUDE_CAMERA3_H
#define ANDROID_INCLUDE_CAMERA3_H
#include <system/camera_metadata.h>
#include "camera_common.h"
/**
* Camera device HAL 3.5[ CAMERA_DEVICE_API_VERSION_3_5 ]
*
* This is the current recommended version of the camera device HAL.
*
* Supports the android.hardware.Camera API, and as of v3.2, the
* android.hardware.camera2 API as LIMITED or above hardware level.
*
* Camera devices that support this version of the HAL must return
* CAMERA_DEVICE_API_VERSION_3_5 in camera_device_t.common.version and in
* camera_info_t.device_version (from camera_module_t.get_camera_info).
*
* CAMERA_DEVICE_API_VERSION_3_3 and above:
* Camera modules that may contain version 3.3 or above devices must
* implement at least version 2.2 of the camera module interface (as defined
* by camera_module_t.common.module_api_version).
*
* CAMERA_DEVICE_API_VERSION_3_2:
* Camera modules that may contain version 3.2 devices must implement at
* least version 2.2 of the camera module interface (as defined by
* camera_module_t.common.module_api_version).
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
* Camera modules that may contain version 3.1 (or 3.0) devices must
* implement at least version 2.0 of the camera module interface
* (as defined by camera_module_t.common.module_api_version).
*
* See camera_common.h for more versioning details.
*
* Documentation index:
* S1. Version history
* S2. Startup and operation sequencing
* S3. Operational modes
* S4. 3A modes and state machines
* S5. Cropping
* S6. Error management
* S7. Key Performance Indicator (KPI) glossary
* S8. Sample Use Cases
* S9. Notes on Controls and Metadata
* S10. Reprocessing flow and controls
*/
/**
* S1. Version history:
*
* 1.0: Initial Android camera HAL (Android 4.0) [camera.h]:
*
* - Converted from C++ CameraHardwareInterface abstraction layer.
*
* - Supports android.hardware.Camera API.
*
* 2.0: Initial release of expanded-capability HAL (Android 4.2) [camera2.h]:
*
* - Sufficient for implementing existing android.hardware.Camera API.
*
* - Allows for ZSL queue in camera service layer
*
* - Not tested for any new features such manual capture control, Bayer RAW
* capture, reprocessing of RAW data.
*
* 3.0: First revision of expanded-capability HAL:
*
* - Major version change since the ABI is completely different. No change to
* the required hardware capabilities or operational model from 2.0.
*
* - Reworked input request and stream queue interfaces: Framework calls into
* HAL with next request and stream buffers already dequeued. Sync framework
* support is included, necessary for efficient implementations.
*
* - Moved triggers into requests, most notifications into results.
*
* - Consolidated all callbacks into framework into one structure, and all
* setup methods into a single initialize() call.
*
* - Made stream configuration into a single call to simplify stream
* management. Bidirectional streams replace STREAM_FROM_STREAM construct.
*
* - Limited mode semantics for older/limited hardware devices.
*
* 3.1: Minor revision of expanded-capability HAL:
*
* - configure_streams passes consumer usage flags to the HAL.
*
* - flush call to drop all in-flight requests/buffers as fast as possible.
*
* 3.2: Minor revision of expanded-capability HAL:
*
* - Deprecates get_metadata_vendor_tag_ops. Please use get_vendor_tag_ops
* in camera_common.h instead.
*
* - register_stream_buffers deprecated. All gralloc buffers provided
* by framework to HAL in process_capture_request may be new at any time.
*
* - add partial result support. process_capture_result may be called
* multiple times with a subset of the available result before the full
* result is available.
*
* - add manual template to camera3_request_template. The applications may
* use this template to control the capture settings directly.
*
* - Rework the bidirectional and input stream specifications.
*
* - change the input buffer return path. The buffer is returned in
* process_capture_result instead of process_capture_request.
*
* 3.3: Minor revision of expanded-capability HAL:
*
* - OPAQUE and YUV reprocessing API updates.
*
* - Basic support for depth output buffers.
*
* - Addition of data_space field to camera3_stream_t.
*
* - Addition of rotation field to camera3_stream_t.
*
* - Addition of camera3 stream configuration operation mode to camera3_stream_configuration_t
*
* 3.4: Minor additions to supported metadata and changes to data_space support
*
* - Add ANDROID_SENSOR_OPAQUE_RAW_SIZE static metadata as mandatory if
* RAW_OPAQUE format is supported.
*
* - Add ANDROID_CONTROL_POST_RAW_SENSITIVITY_BOOST_RANGE static metadata as
* mandatory if any RAW format is supported
*
* - Switch camera3_stream_t data_space field to a more flexible definition,
* using the version 0 definition of dataspace encoding.
*
* - General metadata additions which are available to use for HALv3.2 or
* newer:
* - ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL_3
* - ANDROID_CONTROL_POST_RAW_SENSITIVITY_BOOST
* - ANDROID_CONTROL_POST_RAW_SENSITIVITY_BOOST_RANGE
* - ANDROID_SENSOR_DYNAMIC_BLACK_LEVEL
* - ANDROID_SENSOR_DYNAMIC_WHITE_LEVEL
* - ANDROID_SENSOR_OPAQUE_RAW_SIZE
* - ANDROID_SENSOR_OPTICAL_BLACK_REGIONS
*
* 3.5: Minor revisions to support session parameters and logical multi camera:
*
* - Add ANDROID_REQUEST_AVAILABLE_SESSION_KEYS static metadata, which is
* optional for implementations that want to support session parameters. If support is
* needed, then Hal should populate the list with all available capture request keys
* that can cause severe processing delays when modified by client. Typical examples
* include parameters that require time-consuming HW re-configuration or internal camera
* pipeline update.
*
* - Add a session parameter field to camera3_stream_configuration which can be populated
* by clients with initial values for the keys found in ANDROID_REQUEST_AVAILABLE_SESSION_KEYS.
*
* - Metadata additions for logical multi camera capability:
* - ANDROID_REQUEST_AVAILABLE_CAPABILITIES_LOGICAL_MULTI_CAMERA
* - ANDROID_LOGICAL_MULTI_CAMERA_PHYSICAL_IDS
* - ANDROID_LOGICAL_MULTI_CAMERA_SYNC_TYPE
*
* - Add physical camera id field in camera3_stream, so that for a logical
* multi camera, the application has the option to specify which physical camera
* a particular stream is configured on.
*
* - Add physical camera id and settings field in camera3_capture_request, so that
* for a logical multi camera, the application has the option to specify individual
* settings for a particular physical device.
*
*/
/**
* S2. Startup and general expected operation sequence:
*
* 1. Framework calls camera_module_t->common.open(), which returns a
* hardware_device_t structure.
*
* 2. Framework inspects the hardware_device_t->version field, and instantiates
* the appropriate handler for that version of the camera hardware device. In
* case the version is CAMERA_DEVICE_API_VERSION_3_0, the device is cast to
* a camera3_device_t.
*
* 3. Framework calls camera3_device_t->ops->initialize() with the framework
* callback function pointers. This will only be called this one time after
* open(), before any other functions in the ops structure are called.
*
* 4. The framework calls camera3_device_t->ops->configure_streams() with a list
* of input/output streams to the HAL device.
*
* 5. <= CAMERA_DEVICE_API_VERSION_3_1:
*
* The framework allocates gralloc buffers and calls
* camera3_device_t->ops->register_stream_buffers() for at least one of the
* output streams listed in configure_streams. The same stream is registered
* only once.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* camera3_device_t->ops->register_stream_buffers() is not called and must
* be NULL.
*
* 6. The framework requests default settings for some number of use cases with
* calls to camera3_device_t->ops->construct_default_request_settings(). This
* may occur any time after step 3.
*
* 7. The framework constructs and sends the first capture request to the HAL,
* with settings based on one of the sets of default settings, and with at
* least one output stream, which has been registered earlier by the
* framework. This is sent to the HAL with
* camera3_device_t->ops->process_capture_request(). The HAL must block the
* return of this call until it is ready for the next request to be sent.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* The buffer_handle_t provided in the camera3_stream_buffer_t array
* in the camera3_capture_request_t may be new and never-before-seen
* by the HAL on any given new request.
*
* 8. The framework continues to submit requests, and call
* construct_default_request_settings to get default settings buffers for
* other use cases.
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* The framework may call register_stream_buffers() at this time for
* not-yet-registered streams.
*
* 9. When the capture of a request begins (sensor starts exposing for the
* capture) or processing a reprocess request begins, the HAL
* calls camera3_callback_ops_t->notify() with the SHUTTER event, including
* the frame number and the timestamp for start of exposure. For a reprocess
* request, the timestamp must be the start of exposure of the input image
* which can be looked up with android.sensor.timestamp from
* camera3_capture_request_t.settings when process_capture_request() is
* called.
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* This notify call must be made before the first call to
* process_capture_result() for that frame number.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* The camera3_callback_ops_t->notify() call with the SHUTTER event should
* be made as early as possible since the framework will be unable to
* deliver gralloc buffers to the application layer (for that frame) until
* it has a valid timestamp for the start of exposure (or the input image's
* start of exposure for a reprocess request).
*
* Both partial metadata results and the gralloc buffers may be sent to the
* framework at any time before or after the SHUTTER event.
*
* 10. After some pipeline delay, the HAL begins to return completed captures to
* the framework with camera3_callback_ops_t->process_capture_result(). These
* are returned in the same order as the requests were submitted. Multiple
* requests can be in flight at once, depending on the pipeline depth of the
* camera HAL device.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* Once a buffer is returned by process_capture_result as part of the
* camera3_stream_buffer_t array, and the fence specified by release_fence
* has been signaled (this is a no-op for -1 fences), the ownership of that
* buffer is considered to be transferred back to the framework. After that,
* the HAL must no longer retain that particular buffer, and the
* framework may clean up the memory for it immediately.
*
* process_capture_result may be called multiple times for a single frame,
* each time with a new disjoint piece of metadata and/or set of gralloc
* buffers. The framework will accumulate these partial metadata results
* into one result.
*
* In particular, it is legal for a process_capture_result to be called
* simultaneously for both a frame N and a frame N+1 as long as the
* above rule holds for gralloc buffers (both input and output).
*
* 11. After some time, the framework may stop submitting new requests, wait for
* the existing captures to complete (all buffers filled, all results
* returned), and then call configure_streams() again. This resets the camera
* hardware and pipeline for a new set of input/output streams. Some streams
* may be reused from the previous configuration; if these streams' buffers
* had already been registered with the HAL, they will not be registered
* again. The framework then continues from step 7, if at least one
* registered output stream remains (otherwise, step 5 is required first).
*
* 12. Alternatively, the framework may call camera3_device_t->common->close()
* to end the camera session. This may be called at any time when no other
* calls from the framework are active, although the call may block until all
* in-flight captures have completed (all results returned, all buffers
* filled). After the close call returns, no more calls to the
* camera3_callback_ops_t functions are allowed from the HAL. Once the
* close() call is underway, the framework may not call any other HAL device
* functions.
*
* 13. In case of an error or other asynchronous event, the HAL must call
* camera3_callback_ops_t->notify() with the appropriate error/event
* message. After returning from a fatal device-wide error notification, the
* HAL should act as if close() had been called on it. However, the HAL must
* either cancel or complete all outstanding captures before calling
* notify(), so that once notify() is called with a fatal error, the
* framework will not receive further callbacks from the device. Methods
* besides close() should return -ENODEV or NULL after the notify() method
* returns from a fatal error message.
*/
/**
* S3. Operational modes:
*
* The camera 3 HAL device can implement one of two possible operational modes;
* limited and full. Full support is expected from new higher-end
* devices. Limited mode has hardware requirements roughly in line with those
* for a camera HAL device v1 implementation, and is expected from older or
* inexpensive devices. Full is a strict superset of limited, and they share the
* same essential operational flow, as documented above.
*
* The HAL must indicate its level of support with the
* android.info.supportedHardwareLevel static metadata entry, with 0 indicating
* limited mode, and 1 indicating full mode support.
*
* Roughly speaking, limited-mode devices do not allow for application control
* of capture settings (3A control only), high-rate capture of high-resolution
* images, raw sensor readout, or support for YUV output streams above maximum
* recording resolution (JPEG only for large images).
*
* ** Details of limited mode behavior:
*
* - Limited-mode devices do not need to implement accurate synchronization
* between capture request settings and the actual image data
* captured. Instead, changes to settings may take effect some time in the
* future, and possibly not for the same output frame for each settings
* entry. Rapid changes in settings may result in some settings never being
* used for a capture. However, captures that include high-resolution output
* buffers ( > 1080p ) have to use the settings as specified (but see below
* for processing rate).
*
* - Limited-mode devices do not need to support most of the
* settings/result/static info metadata. Specifically, only the following settings
* are expected to be consumed or produced by a limited-mode HAL device:
*
* android.control.aeAntibandingMode (controls and dynamic)
* android.control.aeExposureCompensation (controls and dynamic)
* android.control.aeLock (controls and dynamic)
* android.control.aeMode (controls and dynamic)
* android.control.aeRegions (controls and dynamic)
* android.control.aeTargetFpsRange (controls and dynamic)
* android.control.aePrecaptureTrigger (controls and dynamic)
* android.control.afMode (controls and dynamic)
* android.control.afRegions (controls and dynamic)
* android.control.awbLock (controls and dynamic)
* android.control.awbMode (controls and dynamic)
* android.control.awbRegions (controls and dynamic)
* android.control.captureIntent (controls and dynamic)
* android.control.effectMode (controls and dynamic)
* android.control.mode (controls and dynamic)
* android.control.sceneMode (controls and dynamic)
* android.control.videoStabilizationMode (controls and dynamic)
* android.control.aeAvailableAntibandingModes (static)
* android.control.aeAvailableModes (static)
* android.control.aeAvailableTargetFpsRanges (static)
* android.control.aeCompensationRange (static)
* android.control.aeCompensationStep (static)
* android.control.afAvailableModes (static)
* android.control.availableEffects (static)
* android.control.availableSceneModes (static)
* android.control.availableVideoStabilizationModes (static)
* android.control.awbAvailableModes (static)
* android.control.maxRegions (static)
* android.control.sceneModeOverrides (static)
* android.control.aeState (dynamic)
* android.control.afState (dynamic)
* android.control.awbState (dynamic)
*
* android.flash.mode (controls and dynamic)
* android.flash.info.available (static)
*
* android.info.supportedHardwareLevel (static)
*
* android.jpeg.gpsCoordinates (controls and dynamic)
* android.jpeg.gpsProcessingMethod (controls and dynamic)
* android.jpeg.gpsTimestamp (controls and dynamic)
* android.jpeg.orientation (controls and dynamic)
* android.jpeg.quality (controls and dynamic)
* android.jpeg.thumbnailQuality (controls and dynamic)
* android.jpeg.thumbnailSize (controls and dynamic)
* android.jpeg.availableThumbnailSizes (static)
* android.jpeg.maxSize (static)
*
* android.lens.info.minimumFocusDistance (static)
*
* android.request.id (controls and dynamic)
*
* android.scaler.cropRegion (controls and dynamic)
* android.scaler.availableStreamConfigurations (static)
* android.scaler.availableMinFrameDurations (static)
* android.scaler.availableStallDurations (static)
* android.scaler.availableMaxDigitalZoom (static)
* android.scaler.maxDigitalZoom (static)
* android.scaler.croppingType (static)
*
* android.sensor.orientation (static)
* android.sensor.timestamp (dynamic)
*
* android.statistics.faceDetectMode (controls and dynamic)
* android.statistics.info.availableFaceDetectModes (static)
* android.statistics.faceIds (dynamic)
* android.statistics.faceLandmarks (dynamic)
* android.statistics.faceRectangles (dynamic)
* android.statistics.faceScores (dynamic)
*
* android.sync.frameNumber (dynamic)
* android.sync.maxLatency (static)
*
* - Captures in limited mode that include high-resolution (> 1080p) output
* buffers may block in process_capture_request() until all the output buffers
* have been filled. A full-mode HAL device must process sequences of
* high-resolution requests at the rate indicated in the static metadata for
* that pixel format. The HAL must still call process_capture_result() to
* provide the output; the framework must simply be prepared for
* process_capture_request() to block until after process_capture_result() for
* that request completes for high-resolution captures for limited-mode
* devices.
*
* - Full-mode devices must support below additional capabilities:
* - 30fps at maximum resolution is preferred, more than 20fps is required.
* - Per frame control (android.sync.maxLatency == PER_FRAME_CONTROL).
* - Sensor manual control metadata. See MANUAL_SENSOR defined in
* android.request.availableCapabilities.
* - Post-processing manual control metadata. See MANUAL_POST_PROCESSING defined
* in android.request.availableCapabilities.
*
*/
/**
* S4. 3A modes and state machines:
*
* While the actual 3A algorithms are up to the HAL implementation, a high-level
* state machine description is defined by the HAL interface, to allow the HAL
* device and the framework to communicate about the current state of 3A, and to
* trigger 3A events.
*
* When the device is opened, all the individual 3A states must be
* STATE_INACTIVE. Stream configuration does not reset 3A. For example, locked
* focus must be maintained across the configure() call.
*
* Triggering a 3A action involves simply setting the relevant trigger entry in
* the settings for the next request to indicate start of trigger. For example,
* the trigger for starting an autofocus scan is setting the entry
* ANDROID_CONTROL_AF_TRIGGER to ANDROID_CONTROL_AF_TRIGGER_START for one
* request, and cancelling an autofocus scan is triggered by setting
* ANDROID_CONTROL_AF_TRIGGER to ANDROID_CONTRL_AF_TRIGGER_CANCEL. Otherwise,
* the entry will not exist, or be set to ANDROID_CONTROL_AF_TRIGGER_IDLE. Each
* request with a trigger entry set to a non-IDLE value will be treated as an
* independent triggering event.
*
* At the top level, 3A is controlled by the ANDROID_CONTROL_MODE setting, which
* selects between no 3A (ANDROID_CONTROL_MODE_OFF), normal AUTO mode
* (ANDROID_CONTROL_MODE_AUTO), and using the scene mode setting
* (ANDROID_CONTROL_USE_SCENE_MODE).
*
* - In OFF mode, each of the individual AE/AF/AWB modes are effectively OFF,
* and none of the capture controls may be overridden by the 3A routines.
*
* - In AUTO mode, Auto-focus, auto-exposure, and auto-whitebalance all run
* their own independent algorithms, and have their own mode, state, and
* trigger metadata entries, as listed in the next section.
*
* - In USE_SCENE_MODE, the value of the ANDROID_CONTROL_SCENE_MODE entry must
* be used to determine the behavior of 3A routines. In SCENE_MODEs other than
* FACE_PRIORITY, the HAL must override the values of
* ANDROId_CONTROL_AE/AWB/AF_MODE to be the mode it prefers for the selected
* SCENE_MODE. For example, the HAL may prefer SCENE_MODE_NIGHT to use
* CONTINUOUS_FOCUS AF mode. Any user selection of AE/AWB/AF_MODE when scene
* must be ignored for these scene modes.
*
* - For SCENE_MODE_FACE_PRIORITY, the AE/AWB/AF_MODE controls work as in
* ANDROID_CONTROL_MODE_AUTO, but the 3A routines must bias toward metering
* and focusing on any detected faces in the scene.
*
* S4.1. Auto-focus settings and result entries:
*
* Main metadata entries:
*
* ANDROID_CONTROL_AF_MODE: Control for selecting the current autofocus
* mode. Set by the framework in the request settings.
*
* AF_MODE_OFF: AF is disabled; the framework/app directly controls lens
* position.
*
* AF_MODE_AUTO: Single-sweep autofocus. No lens movement unless AF is
* triggered.
*
* AF_MODE_MACRO: Single-sweep up-close autofocus. No lens movement unless
* AF is triggered.
*
* AF_MODE_CONTINUOUS_VIDEO: Smooth continuous focusing, for recording
* video. Triggering immediately locks focus in current
* position. Canceling resumes cotinuous focusing.
*
* AF_MODE_CONTINUOUS_PICTURE: Fast continuous focusing, for
* zero-shutter-lag still capture. Triggering locks focus once currently
* active sweep concludes. Canceling resumes continuous focusing.
*
* AF_MODE_EDOF: Advanced extended depth of field focusing. There is no
* autofocus scan, so triggering one or canceling one has no effect.
* Images are focused automatically by the HAL.
*
* ANDROID_CONTROL_AF_STATE: Dynamic metadata describing the current AF
* algorithm state, reported by the HAL in the result metadata.
*
* AF_STATE_INACTIVE: No focusing has been done, or algorithm was
* reset. Lens is not moving. Always the state for MODE_OFF or MODE_EDOF.
* When the device is opened, it must start in this state.
*
* AF_STATE_PASSIVE_SCAN: A continuous focus algorithm is currently scanning
* for good focus. The lens is moving.
*
* AF_STATE_PASSIVE_FOCUSED: A continuous focus algorithm believes it is
* well focused. The lens is not moving. The HAL may spontaneously leave
* this state.
*
* AF_STATE_PASSIVE_UNFOCUSED: A continuous focus algorithm believes it is
* not well focused. The lens is not moving. The HAL may spontaneously
* leave this state.
*
* AF_STATE_ACTIVE_SCAN: A scan triggered by the user is underway.
*
* AF_STATE_FOCUSED_LOCKED: The AF algorithm believes it is focused. The
* lens is not moving.
*
* AF_STATE_NOT_FOCUSED_LOCKED: The AF algorithm has been unable to
* focus. The lens is not moving.
*
* ANDROID_CONTROL_AF_TRIGGER: Control for starting an autofocus scan, the
* meaning of which is mode- and state- dependent. Set by the framework in
* the request settings.
*
* AF_TRIGGER_IDLE: No current trigger.
*
* AF_TRIGGER_START: Trigger start of AF scan. Effect is mode and state
* dependent.
*
* AF_TRIGGER_CANCEL: Cancel current AF scan if any, and reset algorithm to
* default.
*
* Additional metadata entries:
*
* ANDROID_CONTROL_AF_REGIONS: Control for selecting the regions of the FOV
* that should be used to determine good focus. This applies to all AF
* modes that scan for focus. Set by the framework in the request
* settings.
*
* S4.2. Auto-exposure settings and result entries:
*
* Main metadata entries:
*
* ANDROID_CONTROL_AE_MODE: Control for selecting the current auto-exposure
* mode. Set by the framework in the request settings.
*
* AE_MODE_OFF: Autoexposure is disabled; the user controls exposure, gain,
* frame duration, and flash.
*
* AE_MODE_ON: Standard autoexposure, with flash control disabled. User may
* set flash to fire or to torch mode.
*
* AE_MODE_ON_AUTO_FLASH: Standard autoexposure, with flash on at HAL's
* discretion for precapture and still capture. User control of flash
* disabled.
*
* AE_MODE_ON_ALWAYS_FLASH: Standard autoexposure, with flash always fired
* for capture, and at HAL's discretion for precapture.. User control of
* flash disabled.
*
* AE_MODE_ON_AUTO_FLASH_REDEYE: Standard autoexposure, with flash on at
* HAL's discretion for precapture and still capture. Use a flash burst
* at end of precapture sequence to reduce redeye in the final
* picture. User control of flash disabled.
*
* ANDROID_CONTROL_AE_STATE: Dynamic metadata describing the current AE
* algorithm state, reported by the HAL in the result metadata.
*
* AE_STATE_INACTIVE: Initial AE state after mode switch. When the device is
* opened, it must start in this state.
*
* AE_STATE_SEARCHING: AE is not converged to a good value, and is adjusting
* exposure parameters.
*
* AE_STATE_CONVERGED: AE has found good exposure values for the current
* scene, and the exposure parameters are not changing. HAL may
* spontaneously leave this state to search for better solution.
*
* AE_STATE_LOCKED: AE has been locked with the AE_LOCK control. Exposure
* values are not changing.
*
* AE_STATE_FLASH_REQUIRED: The HAL has converged exposure, but believes
* flash is required for a sufficiently bright picture. Used for
* determining if a zero-shutter-lag frame can be used.
*
* AE_STATE_PRECAPTURE: The HAL is in the middle of a precapture
* sequence. Depending on AE mode, this mode may involve firing the
* flash for metering, or a burst of flash pulses for redeye reduction.
*
* ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER: Control for starting a metering
* sequence before capturing a high-quality image. Set by the framework in
* the request settings.
*
* PRECAPTURE_TRIGGER_IDLE: No current trigger.
*
* PRECAPTURE_TRIGGER_START: Start a precapture sequence. The HAL should
* use the subsequent requests to measure good exposure/white balance
* for an upcoming high-resolution capture.
*
* Additional metadata entries:
*
* ANDROID_CONTROL_AE_LOCK: Control for locking AE controls to their current
* values
*
* ANDROID_CONTROL_AE_EXPOSURE_COMPENSATION: Control for adjusting AE
* algorithm target brightness point.
*
* ANDROID_CONTROL_AE_TARGET_FPS_RANGE: Control for selecting the target frame
* rate range for the AE algorithm. The AE routine cannot change the frame
* rate to be outside these bounds.
*
* ANDROID_CONTROL_AE_REGIONS: Control for selecting the regions of the FOV
* that should be used to determine good exposure levels. This applies to
* all AE modes besides OFF.
*
* S4.3. Auto-whitebalance settings and result entries:
*
* Main metadata entries:
*
* ANDROID_CONTROL_AWB_MODE: Control for selecting the current white-balance
* mode.
*
* AWB_MODE_OFF: Auto-whitebalance is disabled. User controls color matrix.
*
* AWB_MODE_AUTO: Automatic white balance is enabled; 3A controls color
* transform, possibly using more complex transforms than a simple
* matrix.
*
* AWB_MODE_INCANDESCENT: Fixed white balance settings good for indoor
* incandescent (tungsten) lighting, roughly 2700K.
*
* AWB_MODE_FLUORESCENT: Fixed white balance settings good for fluorescent
* lighting, roughly 5000K.
*
* AWB_MODE_WARM_FLUORESCENT: Fixed white balance settings good for
* fluorescent lighting, roughly 3000K.
*
* AWB_MODE_DAYLIGHT: Fixed white balance settings good for daylight,
* roughly 5500K.
*
* AWB_MODE_CLOUDY_DAYLIGHT: Fixed white balance settings good for clouded
* daylight, roughly 6500K.
*
* AWB_MODE_TWILIGHT: Fixed white balance settings good for
* near-sunset/sunrise, roughly 15000K.
*
* AWB_MODE_SHADE: Fixed white balance settings good for areas indirectly
* lit by the sun, roughly 7500K.
*
* ANDROID_CONTROL_AWB_STATE: Dynamic metadata describing the current AWB
* algorithm state, reported by the HAL in the result metadata.
*
* AWB_STATE_INACTIVE: Initial AWB state after mode switch. When the device
* is opened, it must start in this state.
*
* AWB_STATE_SEARCHING: AWB is not converged to a good value, and is
* changing color adjustment parameters.
*
* AWB_STATE_CONVERGED: AWB has found good color adjustment values for the
* current scene, and the parameters are not changing. HAL may
* spontaneously leave this state to search for better solution.
*
* AWB_STATE_LOCKED: AWB has been locked with the AWB_LOCK control. Color
* adjustment values are not changing.
*
* Additional metadata entries:
*
* ANDROID_CONTROL_AWB_LOCK: Control for locking AWB color adjustments to
* their current values.
*
* ANDROID_CONTROL_AWB_REGIONS: Control for selecting the regions of the FOV
* that should be used to determine good color balance. This applies only
* to auto-WB mode.
*
* S4.4. General state machine transition notes
*
* Switching between AF, AE, or AWB modes always resets the algorithm's state
* to INACTIVE. Similarly, switching between CONTROL_MODE or
* CONTROL_SCENE_MODE if CONTROL_MODE == USE_SCENE_MODE resets all the
* algorithm states to INACTIVE.
*
* The tables below are per-mode.
*
* S4.5. AF state machines
*
* when enabling AF or changing AF mode
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| Any | AF mode change| INACTIVE | |
*+--------------------+---------------+--------------------+------------------+
*
* mode = AF_MODE_OFF or AF_MODE_EDOF
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | | INACTIVE | Never changes |
*+--------------------+---------------+--------------------+------------------+
*
* mode = AF_MODE_AUTO or AF_MODE_MACRO
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | AF_TRIGGER | ACTIVE_SCAN | Start AF sweep |
*| | | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| ACTIVE_SCAN | AF sweep done | FOCUSED_LOCKED | If AF successful |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| ACTIVE_SCAN | AF sweep done | NOT_FOCUSED_LOCKED | If AF successful |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| ACTIVE_SCAN | AF_CANCEL | INACTIVE | Cancel/reset AF |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Cancel/reset AF |
*+--------------------+---------------+--------------------+------------------+
*| FOCUSED_LOCKED | AF_TRIGGER | ACTIVE_SCAN | Start new sweep |
*| | | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| NOT_FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Cancel/reset AF |
*+--------------------+---------------+--------------------+------------------+
*| NOT_FOCUSED_LOCKED | AF_TRIGGER | ACTIVE_SCAN | Start new sweep |
*| | | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| All states | mode change | INACTIVE | |
*+--------------------+---------------+--------------------+------------------+
*
* mode = AF_MODE_CONTINUOUS_VIDEO
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | HAL initiates | PASSIVE_SCAN | Start AF scan |
*| | new scan | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | AF_TRIGGER | NOT_FOCUSED_LOCKED | AF state query |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | HAL completes | PASSIVE_FOCUSED | End AF scan |
*| | current scan | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | HAL fails | PASSIVE_UNFOCUSED | End AF scan |
*| | current scan | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | AF_TRIGGER | FOCUSED_LOCKED | Immediate trans. |
*| | | | if focus is good |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | AF_TRIGGER | NOT_FOCUSED_LOCKED | Immediate trans. |
*| | | | if focus is bad |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | AF_CANCEL | INACTIVE | Reset lens |
*| | | | position |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_FOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan |
*| | new scan | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_UNFOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan |
*| | new scan | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_FOCUSED | AF_TRIGGER | FOCUSED_LOCKED | Immediate trans. |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_UNFOCUSED | AF_TRIGGER | NOT_FOCUSED_LOCKED | Immediate trans. |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| FOCUSED_LOCKED | AF_TRIGGER | FOCUSED_LOCKED | No effect |
*+--------------------+---------------+--------------------+------------------+
*| FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan |
*+--------------------+---------------+--------------------+------------------+
*| NOT_FOCUSED_LOCKED | AF_TRIGGER | NOT_FOCUSED_LOCKED | No effect |
*+--------------------+---------------+--------------------+------------------+
*| NOT_FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan |
*+--------------------+---------------+--------------------+------------------+
*
* mode = AF_MODE_CONTINUOUS_PICTURE
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | HAL initiates | PASSIVE_SCAN | Start AF scan |
*| | new scan | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | AF_TRIGGER | NOT_FOCUSED_LOCKED | AF state query |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | HAL completes | PASSIVE_FOCUSED | End AF scan |
*| | current scan | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | HAL fails | PASSIVE_UNFOCUSED | End AF scan |
*| | current scan | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | AF_TRIGGER | FOCUSED_LOCKED | Eventual trans. |
*| | | | once focus good |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | AF_TRIGGER | NOT_FOCUSED_LOCKED | Eventual trans. |
*| | | | if cannot focus |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_SCAN | AF_CANCEL | INACTIVE | Reset lens |
*| | | | position |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_FOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan |
*| | new scan | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_UNFOCUSED | HAL initiates | PASSIVE_SCAN | Start AF scan |
*| | new scan | | Lens now moving |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_FOCUSED | AF_TRIGGER | FOCUSED_LOCKED | Immediate trans. |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| PASSIVE_UNFOCUSED | AF_TRIGGER | NOT_FOCUSED_LOCKED | Immediate trans. |
*| | | | Lens now locked |
*+--------------------+---------------+--------------------+------------------+
*| FOCUSED_LOCKED | AF_TRIGGER | FOCUSED_LOCKED | No effect |
*+--------------------+---------------+--------------------+------------------+
*| FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan |
*+--------------------+---------------+--------------------+------------------+
*| NOT_FOCUSED_LOCKED | AF_TRIGGER | NOT_FOCUSED_LOCKED | No effect |
*+--------------------+---------------+--------------------+------------------+
*| NOT_FOCUSED_LOCKED | AF_CANCEL | INACTIVE | Restart AF scan |
*+--------------------+---------------+--------------------+------------------+
*
* S4.6. AE and AWB state machines
*
* The AE and AWB state machines are mostly identical. AE has additional
* FLASH_REQUIRED and PRECAPTURE states. So rows below that refer to those two
* states should be ignored for the AWB state machine.
*
* when enabling AE/AWB or changing AE/AWB mode
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| Any | mode change | INACTIVE | |
*+--------------------+---------------+--------------------+------------------+
*
* mode = AE_MODE_OFF / AWB mode not AUTO
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | | INACTIVE | AE/AWB disabled |
*+--------------------+---------------+--------------------+------------------+
*
* mode = AE_MODE_ON_* / AWB_MODE_AUTO
*| state | trans. cause | new state | notes |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | HAL initiates | SEARCHING | |
*| | AE/AWB scan | | |
*+--------------------+---------------+--------------------+------------------+
*| INACTIVE | AE/AWB_LOCK | LOCKED | values locked |
*| | on | | |
*+--------------------+---------------+--------------------+------------------+
*| SEARCHING | HAL finishes | CONVERGED | good values, not |
*| | AE/AWB scan | | changing |
*+--------------------+---------------+--------------------+------------------+
*| SEARCHING | HAL finishes | FLASH_REQUIRED | converged but too|
*| | AE scan | | dark w/o flash |
*+--------------------+---------------+--------------------+------------------+
*| SEARCHING | AE/AWB_LOCK | LOCKED | values locked |
*| | on | | |
*+--------------------+---------------+--------------------+------------------+
*| CONVERGED | HAL initiates | SEARCHING | values locked |
*| | AE/AWB scan | | |
*+--------------------+---------------+--------------------+------------------+
*| CONVERGED | AE/AWB_LOCK | LOCKED | values locked |
*| | on | | |
*+--------------------+---------------+--------------------+------------------+
*| FLASH_REQUIRED | HAL initiates | SEARCHING | values locked |
*| | AE/AWB scan | | |
*+--------------------+---------------+--------------------+------------------+
*| FLASH_REQUIRED | AE/AWB_LOCK | LOCKED | values locked |
*| | on | | |
*+--------------------+---------------+--------------------+------------------+
*| LOCKED | AE/AWB_LOCK | SEARCHING | values not good |
*| | off | | after unlock |
*+--------------------+---------------+--------------------+------------------+
*| LOCKED | AE/AWB_LOCK | CONVERGED | values good |
*| | off | | after unlock |
*+--------------------+---------------+--------------------+------------------+
*| LOCKED | AE_LOCK | FLASH_REQUIRED | exposure good, |
*| | off | | but too dark |
*+--------------------+---------------+--------------------+------------------+
*| All AE states | PRECAPTURE_ | PRECAPTURE | Start precapture |
*| | START | | sequence |
*+--------------------+---------------+--------------------+------------------+
*| PRECAPTURE | Sequence done.| CONVERGED | Ready for high- |
*| | AE_LOCK off | | quality capture |
*+--------------------+---------------+--------------------+------------------+
*| PRECAPTURE | Sequence done.| LOCKED | Ready for high- |
*| | AE_LOCK on | | quality capture |
*+--------------------+---------------+--------------------+------------------+
*
*/
/**
* S5. Cropping:
*
* Cropping of the full pixel array (for digital zoom and other use cases where
* a smaller FOV is desirable) is communicated through the
* ANDROID_SCALER_CROP_REGION setting. This is a per-request setting, and can
* change on a per-request basis, which is critical for implementing smooth
* digital zoom.
*
* The region is defined as a rectangle (x, y, width, height), with (x, y)
* describing the top-left corner of the rectangle. The rectangle is defined on
* the coordinate system of the sensor active pixel array, with (0,0) being the
* top-left pixel of the active pixel array. Therefore, the width and height
* cannot be larger than the dimensions reported in the
* ANDROID_SENSOR_ACTIVE_PIXEL_ARRAY static info field. The minimum allowed
* width and height are reported by the HAL through the
* ANDROID_SCALER_MAX_DIGITAL_ZOOM static info field, which describes the
* maximum supported zoom factor. Therefore, the minimum crop region width and
* height are:
*
* {width, height} =
* { floor(ANDROID_SENSOR_ACTIVE_PIXEL_ARRAY[0] /
* ANDROID_SCALER_MAX_DIGITAL_ZOOM),
* floor(ANDROID_SENSOR_ACTIVE_PIXEL_ARRAY[1] /
* ANDROID_SCALER_MAX_DIGITAL_ZOOM) }
*
* If the crop region needs to fulfill specific requirements (for example, it
* needs to start on even coordinates, and its width/height needs to be even),
* the HAL must do the necessary rounding and write out the final crop region
* used in the output result metadata. Similarly, if the HAL implements video
* stabilization, it must adjust the result crop region to describe the region
* actually included in the output after video stabilization is applied. In
* general, a camera-using application must be able to determine the field of
* view it is receiving based on the crop region, the dimensions of the image
* sensor, and the lens focal length.
*
* It is assumed that the cropping is applied after raw to other color space
* conversion. Raw streams (RAW16 and RAW_OPAQUE) don't have this conversion stage,
* and are not croppable. Therefore, the crop region must be ignored by the HAL
* for raw streams.
*
* Since the crop region applies to all non-raw streams, which may have different aspect
* ratios than the crop region, the exact sensor region used for each stream may
* be smaller than the crop region. Specifically, each stream should maintain
* square pixels and its aspect ratio by minimally further cropping the defined
* crop region. If the stream's aspect ratio is wider than the crop region, the
* stream should be further cropped vertically, and if the stream's aspect ratio
* is narrower than the crop region, the stream should be further cropped
* horizontally.
*
* In all cases, the stream crop must be centered within the full crop region,
* and each stream is only either cropped horizontally or vertical relative to
* the full crop region, never both.
*
* For example, if two streams are defined, a 640x480 stream (4:3 aspect), and a
* 1280x720 stream (16:9 aspect), below demonstrates the expected output regions
* for each stream for a few sample crop regions, on a hypothetical 3 MP (2000 x
* 1500 pixel array) sensor.
*
* Crop region: (500, 375, 1000, 750) (4:3 aspect ratio)
*
* 640x480 stream crop: (500, 375, 1000, 750) (equal to crop region)
* 1280x720 stream crop: (500, 469, 1000, 562) (marked with =)
*
* 0 1000 2000
* +---------+---------+---------+----------+
* | Active pixel array |
* | |
* | |
* + +-------------------+ + 375
* | | | |
* | O===================O |
* | I 1280x720 stream I |
* + I I + 750
* | I I |
* | O===================O |
* | | | |
* + +-------------------+ + 1125
* | Crop region, 640x480 stream |
* | |
* | |
* +---------+---------+---------+----------+ 1500
*
* Crop region: (500, 375, 1333, 750) (16:9 aspect ratio)
*
* 640x480 stream crop: (666, 375, 1000, 750) (marked with =)
* 1280x720 stream crop: (500, 375, 1333, 750) (equal to crop region)
*
* 0 1000 2000
* +---------+---------+---------+----------+
* | Active pixel array |
* | |
* | |
* + +---O==================O---+ + 375
* | | I 640x480 stream I | |
* | | I I | |
* | | I I | |
* + | I I | + 750
* | | I I | |
* | | I I | |
* | | I I | |
* + +---O==================O---+ + 1125
* | Crop region, 1280x720 stream |
* | |
* | |
* +---------+---------+---------+----------+ 1500
*
* Crop region: (500, 375, 750, 750) (1:1 aspect ratio)
*
* 640x480 stream crop: (500, 469, 750, 562) (marked with =)
* 1280x720 stream crop: (500, 543, 750, 414) (marged with #)
*
* 0 1000 2000
* +---------+---------+---------+----------+
* | Active pixel array |
* | |
* | |
* + +--------------+ + 375
* | O==============O |
* | ################ |
* | # # |
* + # # + 750
* | # # |
* | ################ 1280x720 |
* | O==============O 640x480 |
* + +--------------+ + 1125
* | Crop region |
* | |
* | |
* +---------+---------+---------+----------+ 1500
*
* And a final example, a 1024x1024 square aspect ratio stream instead of the
* 480p stream:
*
* Crop region: (500, 375, 1000, 750) (4:3 aspect ratio)
*
* 1024x1024 stream crop: (625, 375, 750, 750) (marked with #)
* 1280x720 stream crop: (500, 469, 1000, 562) (marked with =)
*
* 0 1000 2000
* +---------+---------+---------+----------+
* | Active pixel array |
* | |
* | 1024x1024 stream |
* + +--###############--+ + 375
* | | # # | |
* | O===================O |
* | I 1280x720 stream I |
* + I I + 750
* | I I |
* | O===================O |
* | | # # | |
* + +--###############--+ + 1125
* | Crop region |
* | |
* | |
* +---------+---------+---------+----------+ 1500
*
*/
/**
* S6. Error management:
*
* Camera HAL device ops functions that have a return value will all return
* -ENODEV / NULL in case of a serious error. This means the device cannot
* continue operation, and must be closed by the framework. Once this error is
* returned by some method, or if notify() is called with ERROR_DEVICE, only
* the close() method can be called successfully. All other methods will return
* -ENODEV / NULL.
*
* If a device op is called in the wrong sequence, for example if the framework
* calls configure_streams() is called before initialize(), the device must
* return -ENOSYS from the call, and do nothing.
*
* Transient errors in image capture must be reported through notify() as follows:
*
* - The failure of an entire capture to occur must be reported by the HAL by
* calling notify() with ERROR_REQUEST. Individual errors for the result
* metadata or the output buffers must not be reported in this case.
*
* - If the metadata for a capture cannot be produced, but some image buffers
* were filled, the HAL must call notify() with ERROR_RESULT.
*
* - If an output image buffer could not be filled, but either the metadata was
* produced or some other buffers were filled, the HAL must call notify() with
* ERROR_BUFFER for each failed buffer.
*
* In each of these transient failure cases, the HAL must still call
* process_capture_result, with valid output and input (if an input buffer was
* submitted) buffer_handle_t. If the result metadata could not be produced, it
* should be NULL. If some buffers could not be filled, they must be returned with
* process_capture_result in the error state, their release fences must be set to
* the acquire fences passed by the framework, or -1 if they have been waited on by
* the HAL already.
*
* Invalid input arguments result in -EINVAL from the appropriate methods. In
* that case, the framework must act as if that call had never been made.
*
*/
/**
* S7. Key Performance Indicator (KPI) glossary:
*
* This includes some critical definitions that are used by KPI metrics.
*
* Pipeline Latency:
* For a given capture request, the duration from the framework calling
* process_capture_request to the HAL sending capture result and all buffers
* back by process_capture_result call. To make the Pipeline Latency measure
* independent of frame rate, it is measured by frame count.
*
* For example, when frame rate is 30 (fps), the frame duration (time interval
* between adjacent frame capture time) is 33 (ms).
* If it takes 5 frames for framework to get the result and buffers back for
* a given request, then the Pipeline Latency is 5 (frames), instead of
* 5 x 33 = 165 (ms).
*
* The Pipeline Latency is determined by android.request.pipelineDepth and
* android.request.pipelineMaxDepth, see their definitions for more details.
*
*/
/**
* S8. Sample Use Cases:
*
* This includes some typical use case examples the camera HAL may support.
*
* S8.1 Zero Shutter Lag (ZSL) with CAMERA3_STREAM_BIDIRECTIONAL stream.
*
* For this use case, the bidirectional stream will be used by the framework as follows:
*
* 1. The framework includes a buffer from this stream as output buffer in a
* request as normal.
*
* 2. Once the HAL device returns a filled output buffer to the framework,
* the framework may do one of two things with the filled buffer:
*
* 2. a. The framework uses the filled data, and returns the now-used buffer
* to the stream queue for reuse. This behavior exactly matches the
* OUTPUT type of stream.
*
* 2. b. The framework wants to reprocess the filled data, and uses the
* buffer as an input buffer for a request. Once the HAL device has
* used the reprocessing buffer, it then returns it to the
* framework. The framework then returns the now-used buffer to the
* stream queue for reuse.
*
* 3. The HAL device will be given the buffer again as an output buffer for
* a request at some future point.
*
* For ZSL use case, the pixel format for bidirectional stream will be
* HAL_PIXEL_FORMAT_RAW_OPAQUE or HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED if it
* is listed in android.scaler.availableInputOutputFormatsMap. When
* HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED is used, the gralloc
* usage flags for the consumer endpoint will be set to GRALLOC_USAGE_HW_CAMERA_ZSL.
* A configuration stream list that has BIDIRECTIONAL stream used as input, will
* usually also have a distinct OUTPUT stream to get the reprocessing data. For example,
* for the ZSL use case, the stream list might be configured with the following:
*
* - A HAL_PIXEL_FORMAT_RAW_OPAQUE bidirectional stream is used
* as input.
* - And a HAL_PIXEL_FORMAT_BLOB (JPEG) output stream.
*
* S8.2 ZSL (OPAQUE) reprocessing with CAMERA3_STREAM_INPUT stream.
*
* CAMERA_DEVICE_API_VERSION_3_3:
* When OPAQUE_REPROCESSING capability is supported by the camera device, the INPUT stream
* can be used for application/framework implemented use case like Zero Shutter Lag (ZSL).
* This kind of stream will be used by the framework as follows:
*
* 1. Application/framework configures an opaque (RAW or YUV based) format output stream that is
* used to produce the ZSL output buffers. The stream pixel format will be
* HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED.
*
* 2. Application/framework configures an opaque format input stream that is used to
* send the reprocessing ZSL buffers to the HAL. The stream pixel format will
* also be HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED.
*
* 3. Application/framework configures a YUV/JPEG output stream that is used to receive the
* reprocessed data. The stream pixel format will be YCbCr_420/HAL_PIXEL_FORMAT_BLOB.
*
* 4. Application/framework picks a ZSL buffer from the ZSL output stream when a ZSL capture is
* issued by the application, and sends the data back as an input buffer in a
* reprocessing request, then sends to the HAL for reprocessing.
*
* 5. The HAL sends back the output YUV/JPEG result to framework.
*
* The HAL can select the actual opaque buffer format and configure the ISP pipeline
* appropriately based on the HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED format and
* the gralloc usage flag GRALLOC_USAGE_HW_CAMERA_ZSL.
* S8.3 YUV reprocessing with CAMERA3_STREAM_INPUT stream.
*
* When YUV reprocessing is supported by the HAL, the INPUT stream
* can be used for the YUV reprocessing use cases like lucky-shot and image fusion.
* This kind of stream will be used by the framework as follows:
*
* 1. Application/framework configures an YCbCr_420 format output stream that is
* used to produce the output buffers.
*
* 2. Application/framework configures an YCbCr_420 format input stream that is used to
* send the reprocessing YUV buffers to the HAL.
*
* 3. Application/framework configures a YUV/JPEG output stream that is used to receive the
* reprocessed data. The stream pixel format will be YCbCr_420/HAL_PIXEL_FORMAT_BLOB.
*
* 4. Application/framework processes the output buffers (could be as simple as picking
* an output buffer directly) from the output stream when a capture is issued, and sends
* the data back as an input buffer in a reprocessing request, then sends to the HAL
* for reprocessing.
*
* 5. The HAL sends back the output YUV/JPEG result to framework.
*
*/
/**
* S9. Notes on Controls and Metadata
*
* This section contains notes about the interpretation and usage of various metadata tags.
*
* S9.1 HIGH_QUALITY and FAST modes.
*
* Many camera post-processing blocks may be listed as having HIGH_QUALITY,
* FAST, and OFF operating modes. These blocks will typically also have an
* 'available modes' tag representing which of these operating modes are
* available on a given device. The general policy regarding implementing
* these modes is as follows:
*
* 1. Operating mode controls of hardware blocks that cannot be disabled
* must not list OFF in their corresponding 'available modes' tags.
*
* 2. OFF will always be included in their corresponding 'available modes'
* tag if it is possible to disable that hardware block.
*
* 3. FAST must always be included in the 'available modes' tags for all
* post-processing blocks supported on the device. If a post-processing
* block also has a slower and higher quality operating mode that does
* not meet the framerate requirements for FAST mode, HIGH_QUALITY should
* be included in the 'available modes' tag to represent this operating
* mode.
*/
/**
* S10. Reprocessing flow and controls
*
* This section describes the OPAQUE and YUV reprocessing flow and controls. OPAQUE reprocessing
* uses an opaque format that is not directly application-visible, and the application can
* only select some of the output buffers and send back to HAL for reprocessing, while YUV
* reprocessing gives the application opportunity to process the buffers before reprocessing.
*
* S8 gives the stream configurations for the typical reprocessing uses cases,
* this section specifies the buffer flow and controls in more details.
*
* S10.1 OPAQUE (typically for ZSL use case) reprocessing flow and controls
*
* For OPAQUE reprocessing (e.g. ZSL) use case, after the application creates the specific
* output and input streams, runtime buffer flow and controls are specified as below:
*
* 1. Application starts output streaming by sending repeating requests for output
* opaque buffers and preview. The buffers are held by an application
* maintained circular buffer. The requests are based on CAMERA3_TEMPLATE_ZERO_SHUTTER_LAG
* capture template, which should have all necessary settings that guarantee output
* frame rate is not slowed down relative to sensor output frame rate.
*
* 2. When a capture is issued, the application selects one output buffer based
* on application buffer selection logic, e.g. good AE and AF statistics etc.
* Application then creates an reprocess request based on the capture result associated
* with this selected buffer. The selected output buffer is now added to this reprocess
* request as an input buffer, the output buffer of this reprocess request should be
* either JPEG output buffer or YUV output buffer, or both, depending on the application
* choice.
*
* 3. Application then alters the reprocess settings to get best image quality. The HAL must
* support and only support below controls if the HAL support OPAQUE_REPROCESSING capability:
* - android.jpeg.* (if JPEG buffer is included as one of the output)
* - android.noiseReduction.mode (change to HIGH_QUALITY if it is supported)
* - android.edge.mode (change to HIGH_QUALITY if it is supported)
* All other controls must be ignored by the HAL.
* 4. HAL processed the input buffer and return the output buffers in the capture results
* as normal.
*
* S10.2 YUV reprocessing flow and controls
*
* The YUV reprocessing buffer flow is similar as OPAQUE reprocessing, with below difference:
*
* 1. Application may want to have finer granularity control of the intermediate YUV images
* (before reprocessing). For example, application may choose
* - android.noiseReduction.mode == MINIMAL
* to make sure the no YUV domain noise reduction has applied to the output YUV buffers,
* then it can do its own advanced noise reduction on them. For OPAQUE reprocessing case, this
* doesn't matter, as long as the final reprocessed image has the best quality.
* 2. Application may modify the YUV output buffer data. For example, for image fusion use
* case, where multiple output images are merged together to improve the signal-to-noise
* ratio (SNR). The input buffer may be generated from multiple buffers by the application.
* To avoid excessive amount of noise reduction and insufficient amount of edge enhancement
* being applied to the input buffer, the application can hint the HAL how much effective
* exposure time improvement has been done by the application, then the HAL can adjust the
* noise reduction and edge enhancement paramters to get best reprocessed image quality.
* Below tag can be used for this purpose:
* - android.reprocess.effectiveExposureFactor
* The value would be exposure time increase factor applied to the original output image,
* for example, if there are N image merged, the exposure time increase factor would be up
* to sqrt(N). See this tag spec for more details.
*
* S10.3 Reprocessing pipeline characteristics
*
* Reprocessing pipeline has below different characteristics comparing with normal output
* pipeline:
*
* 1. The reprocessing result can be returned ahead of the pending normal output results. But
* the FIFO ordering must be maintained for all reprocessing results. For example, there are
* below requests (A stands for output requests, B stands for reprocessing requests)
* being processed by the HAL:
* A1, A2, A3, A4, B1, A5, B2, A6...
* result of B1 can be returned before A1-A4, but result of B2 must be returned after B1.
* 2. Single input rule: For a given reprocessing request, all output buffers must be from the
* input buffer, rather than sensor output. For example, if a reprocess request include both
* JPEG and preview buffers, all output buffers must be produced from the input buffer
* included by the reprocessing request, rather than sensor. The HAL must not output preview
* buffers from sensor, while output JPEG buffer from the input buffer.
* 3. Input buffer will be from camera output directly (ZSL case) or indirectly(image fusion
* case). For the case where buffer is modified, the size will remain same. The HAL can
* notify CAMERA3_MSG_ERROR_REQUEST if buffer from unknown source is sent.
* 4. Result as reprocessing request: The HAL can expect that a reprocessing request is a copy
* of one of the output results with minor allowed setting changes. The HAL can notify
* CAMERA3_MSG_ERROR_REQUEST if a request from unknown source is issued.
* 5. Output buffers may not be used as inputs across the configure stream boundary, This is
* because an opaque stream like the ZSL output stream may have different actual image size
* inside of the ZSL buffer to save power and bandwidth for smaller resolution JPEG capture.
* The HAL may notify CAMERA3_MSG_ERROR_REQUEST if this case occurs.
* 6. HAL Reprocess requests error reporting during flush should follow the same rule specified
* by flush() method.
*
*/
__BEGIN_DECLS
struct camera3_device;
/**********************************************************************
*
* Camera3 stream and stream buffer definitions.
*
* These structs and enums define the handles and contents of the input and
* output streams connecting the HAL to various framework and application buffer
* consumers. Each stream is backed by a gralloc buffer queue.
*
*/
/**
* camera3_stream_type_t:
*
* The type of the camera stream, which defines whether the camera HAL device is
* the producer or the consumer for that stream, and how the buffers of the
* stream relate to the other streams.
*/
typedef enum camera3_stream_type {
/**
* This stream is an output stream; the camera HAL device will be
* responsible for filling buffers from this stream with newly captured or
* reprocessed image data.
*/
CAMERA3_STREAM_OUTPUT = 0,
/**
* This stream is an input stream; the camera HAL device will be responsible
* for reading buffers from this stream and sending them through the camera
* processing pipeline, as if the buffer was a newly captured image from the
* imager.
*
* The pixel format for input stream can be any format reported by
* android.scaler.availableInputOutputFormatsMap. The pixel format of the
* output stream that is used to produce the reprocessing data may be any
* format reported by android.scaler.availableStreamConfigurations. The
* supported input/output stream combinations depends the camera device
* capabilities, see android.scaler.availableInputOutputFormatsMap for
* stream map details.
*
* This kind of stream is generally used to reprocess data into higher
* quality images (that otherwise would cause a frame rate performance
* loss), or to do off-line reprocessing.
*
* CAMERA_DEVICE_API_VERSION_3_3:
* The typical use cases are OPAQUE (typically ZSL) and YUV reprocessing,
* see S8.2, S8.3 and S10 for more details.
*/
CAMERA3_STREAM_INPUT = 1,
/**
* This stream can be used for input and output. Typically, the stream is
* used as an output stream, but occasionally one already-filled buffer may
* be sent back to the HAL device for reprocessing.
*
* This kind of stream is meant generally for Zero Shutter Lag (ZSL)
* features, where copying the captured image from the output buffer to the
* reprocessing input buffer would be expensive. See S8.1 for more details.
*
* Note that the HAL will always be reprocessing data it produced.
*
*/
CAMERA3_STREAM_BIDIRECTIONAL = 2,
/**
* Total number of framework-defined stream types
*/
CAMERA3_NUM_STREAM_TYPES
} camera3_stream_type_t;
/**
* camera3_stream_rotation_t:
*
* The required counterclockwise rotation of camera stream.
*/
typedef enum camera3_stream_rotation {
/* No rotation */
CAMERA3_STREAM_ROTATION_0 = 0,
/* Rotate by 90 degree counterclockwise */
CAMERA3_STREAM_ROTATION_90 = 1,
/* Rotate by 180 degree counterclockwise */
CAMERA3_STREAM_ROTATION_180 = 2,
/* Rotate by 270 degree counterclockwise */
CAMERA3_STREAM_ROTATION_270 = 3
} camera3_stream_rotation_t;
/**
* camera3_stream_configuration_mode_t:
*
* This defines the general operation mode for the HAL (for a given stream configuration), where
* modes besides NORMAL have different semantics, and usually limit the generality of the API in
* exchange for higher performance in some particular area.
*/
typedef enum camera3_stream_configuration_mode {
/**
* Normal stream configuration operation mode. This is the default camera operation mode,
* where all semantics of HAL APIs and metadata controls apply.
*/
CAMERA3_STREAM_CONFIGURATION_NORMAL_MODE = 0,
/**
* Special constrained high speed operation mode for devices that can not support high
* speed output in NORMAL mode. All streams in this configuration are operating at high speed
* mode and have different characteristics and limitations to achieve high speed output.
* The NORMAL mode can still be used for high speed output if the HAL can support high speed
* output while satisfying all the semantics of HAL APIs and metadata controls. It is
* recommended for the HAL to support high speed output in NORMAL mode (by advertising the high
* speed FPS ranges in android.control.aeAvailableTargetFpsRanges) if possible.
*
* This mode has below limitations/requirements:
*
* 1. The HAL must support up to 2 streams with sizes reported by
* android.control.availableHighSpeedVideoConfigurations.
* 2. In this mode, the HAL is expected to output up to 120fps or higher. This mode must
* support the targeted FPS range and size configurations reported by
* android.control.availableHighSpeedVideoConfigurations.
* 3. The HAL must support HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED output stream format.
* 4. To achieve efficient high speed streaming, the HAL may have to aggregate
* multiple frames together and send to camera device for processing where the request
* controls are same for all the frames in this batch (batch mode). The HAL must support
* max batch size and the max batch size requirements defined by
* android.control.availableHighSpeedVideoConfigurations.
* 5. In this mode, the HAL must override aeMode, awbMode, and afMode to ON, ON, and
* CONTINUOUS_VIDEO, respectively. All post-processing block mode controls must be
* overridden to be FAST. Therefore, no manual control of capture and post-processing
* parameters is possible. All other controls operate the same as when
* android.control.mode == AUTO. This means that all other android.control.* fields
* must continue to work, such as
*
* android.control.aeTargetFpsRange
* android.control.aeExposureCompensation
* android.control.aeLock
* android.control.awbLock
* android.control.effectMode
* android.control.aeRegions
* android.control.afRegions
* android.control.awbRegions
* android.control.afTrigger
* android.control.aePrecaptureTrigger
*
* Outside of android.control.*, the following controls must work:
*
* android.flash.mode (TORCH mode only, automatic flash for still capture will not work
* since aeMode is ON)
* android.lens.opticalStabilizationMode (if it is supported)
* android.scaler.cropRegion
* android.statistics.faceDetectMode (if it is supported)
* 6. To reduce the amount of data passed across process boundaries at
* high frame rate, within one batch, camera framework only propagates
* the last shutter notify and the last capture results (including partial
* results and final result) to the app. The shutter notifies and capture
* results for the other requests in the batch are derived by
* the camera framework. As a result, the HAL can return empty metadata
* except for the last result in the batch.
*
* For more details about high speed stream requirements, see
* android.control.availableHighSpeedVideoConfigurations and CONSTRAINED_HIGH_SPEED_VIDEO
* capability defined in android.request.availableCapabilities.
*
* This mode only needs to be supported by HALs that include CONSTRAINED_HIGH_SPEED_VIDEO in
* the android.request.availableCapabilities static metadata.
*/
CAMERA3_STREAM_CONFIGURATION_CONSTRAINED_HIGH_SPEED_MODE = 1,
/**
* First value for vendor-defined stream configuration modes.
*/
CAMERA3_VENDOR_STREAM_CONFIGURATION_MODE_START = 0x8000
} camera3_stream_configuration_mode_t;
/**
* camera3_stream_t:
*
* A handle to a single camera input or output stream. A stream is defined by
* the framework by its buffer resolution and format, and additionally by the
* HAL with the gralloc usage flags and the maximum in-flight buffer count.
*
* The stream structures are owned by the framework, but pointers to a
* camera3_stream passed into the HAL by configure_streams() are valid until the
* end of the first subsequent configure_streams() call that _does not_ include
* that camera3_stream as an argument, or until the end of the close() call.
*
* All camera3_stream framework-controlled members are immutable once the
* camera3_stream is passed into configure_streams(). The HAL may only change
* the HAL-controlled parameters during a configure_streams() call, except for
* the contents of the private pointer.
*
* If a configure_streams() call returns a non-fatal error, all active streams
* remain valid as if configure_streams() had not been called.
*
* The endpoint of the stream is not visible to the camera HAL device.
* In DEVICE_API_VERSION_3_1, this was changed to share consumer usage flags
* on streams where the camera is a producer (OUTPUT and BIDIRECTIONAL stream
* types) see the usage field below.
*/
typedef struct camera3_stream {
/*****
* Set by framework before configure_streams()
*/
/**
* The type of the stream, one of the camera3_stream_type_t values.
*/
int stream_type;
/**
* The width in pixels of the buffers in this stream
*/
uint32_t width;
/**
* The height in pixels of the buffers in this stream
*/
uint32_t height;
/**
* The pixel format for the buffers in this stream. Format is a value from
* the HAL_PIXEL_FORMAT_* list in system/core/include/system/graphics.h, or
* from device-specific headers.
*
* If HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED is used, then the platform
* gralloc module will select a format based on the usage flags provided by
* the camera device and the other endpoint of the stream.
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* The camera HAL device must inspect the buffers handed to it in the
* subsequent register_stream_buffers() call to obtain the
* implementation-specific format details, if necessary.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* register_stream_buffers() won't be called by the framework, so the HAL
* should configure the ISP and sensor pipeline based purely on the sizes,
* usage flags, and formats for the configured streams.
*/
int format;
/*****
* Set by HAL during configure_streams().
*/
/**
* The gralloc usage flags for this stream, as needed by the HAL. The usage
* flags are defined in gralloc.h (GRALLOC_USAGE_*), or in device-specific
* headers.
*
* For output streams, these are the HAL's producer usage flags. For input
* streams, these are the HAL's consumer usage flags. The usage flags from
* the producer and the consumer will be combined together and then passed
* to the platform gralloc HAL module for allocating the gralloc buffers for
* each stream.
*
* Version information:
*
* == CAMERA_DEVICE_API_VERSION_3_0:
*
* No initial value guaranteed when passed via configure_streams().
* HAL may not use this field as input, and must write over this field
* with its usage flags.
*
* >= CAMERA_DEVICE_API_VERSION_3_1:
*
* For stream_type OUTPUT and BIDIRECTIONAL, when passed via
* configure_streams(), the initial value of this is the consumer's
* usage flags. The HAL may use these consumer flags to decide stream
* configuration.
* For stream_type INPUT, when passed via configure_streams(), the initial
* value of this is 0.
* For all streams passed via configure_streams(), the HAL must write
* over this field with its usage flags.
*
* From Android O, the usage flag for an output stream may be bitwise
* combination of usage flags for multiple consumers, for the purpose of
* sharing one camera stream between those consumers. The HAL must fail
* configure_streams call with -EINVAL if the combined flags cannot be
* supported due to imcompatible buffer format, dataSpace, or other hardware
* limitations.
*/
uint32_t usage;
/**
* The maximum number of buffers the HAL device may need to have dequeued at
* the same time. The HAL device may not have more buffers in-flight from
* this stream than this value.
*/
uint32_t max_buffers;
/**
* A handle to HAL-private information for the stream. Will not be inspected
* by the framework code.
*/
void *priv;
/**
* A field that describes the contents of the buffer. The format and buffer
* dimensions define the memory layout and structure of the stream buffers,
* while dataSpace defines the meaning of the data within the buffer.
*
* For most formats, dataSpace defines the color space of the image data.
* In addition, for some formats, dataSpace indicates whether image- or
* depth-based data is requested. See system/core/include/system/graphics.h
* for details of formats and valid dataSpace values for each format.
*
* Version information:
*
* < CAMERA_DEVICE_API_VERSION_3_3:
*
* Not defined and should not be accessed. dataSpace should be assumed to
* be HAL_DATASPACE_UNKNOWN, and the appropriate color space, etc, should
* be determined from the usage flags and the format.
*
* = CAMERA_DEVICE_API_VERSION_3_3:
*
* Always set by the camera service. HAL must use this dataSpace to
* configure the stream to the correct colorspace, or to select between
* color and depth outputs if supported. The dataspace values are the
* legacy definitions in graphics.h
*
* >= CAMERA_DEVICE_API_VERSION_3_4:
*
* Always set by the camera service. HAL must use this dataSpace to
* configure the stream to the correct colorspace, or to select between
* color and depth outputs if supported. The dataspace values are set
* using the V0 dataspace definitions in graphics.h
*/
android_dataspace_t data_space;
/**
* The required output rotation of the stream, one of
* the camera3_stream_rotation_t values. This must be inspected by HAL along
* with stream width and height. For example, if the rotation is 90 degree
* and the stream width and height is 720 and 1280 respectively, camera service
* will supply buffers of size 720x1280, and HAL should capture a 1280x720 image
* and rotate the image by 90 degree counterclockwise. The rotation field is
* no-op when the stream type is input. Camera HAL must ignore the rotation
* field for an input stream.
*
* <= CAMERA_DEVICE_API_VERSION_3_2:
*
* Not defined and must not be accessed. HAL must not apply any rotation
* on output images.
*
* >= CAMERA_DEVICE_API_VERSION_3_3:
*
* Always set by camera service. HAL must inspect this field during stream
* configuration and returns -EINVAL if HAL cannot perform such rotation.
* HAL must always support CAMERA3_STREAM_ROTATION_0, so a
* configure_streams() call must not fail for unsupported rotation if
* rotation field of all streams is CAMERA3_STREAM_ROTATION_0.
*
*/
int rotation;
/**
* The physical camera id this stream belongs to.
*
* <= CAMERA_DEVICE_API_VERISON_3_4:
*
* Not defined and must not be accessed.
*
* >= CAMERA_DEVICE_API_VERISON_3_5:
*
* Always set by camera service. If the camera device is not a logical
* multi camera, or if the camera is a logical multi camera but the stream
* is not a physical output stream, this field will point to a 0-length
* string.
*
* A logical multi camera is a camera device backed by multiple physical
* cameras that are also exposed to the application. And for a logical
* multi camera, a physical output stream is an output stream specifically
* requested on an underlying physical camera.
*
* For an input stream, this field is guaranteed to be a 0-length string.
*/
const char* physical_camera_id;
/**
* This should be one of the camera3_stream_rotation_t values except for
* CAMERA3_STREAM_ROTATION_180.
* When setting to CAMERA3_STREAM_ROTATION_90 or CAMERA3_STREAM_ROTATION_270, HAL would crop,
* rotate the frame by the specified degrees clockwise and scale it up to original size.
* In Chrome OS, it's possible to have a portrait activity run in a landscape screen with
* landscape-mounted camera. The activity would show stretched or rotated preview because it
* does not expect to receive landscape preview frames. To solve this problem, we ask HAL to
* crop, rotate and scale the frames and modify CameraCharacteristics.SENSOR_ORIENTATION
* accordingly to imitate a portrait camera.
* Setting it to CAMERA3_STREAM_ROTATION_0 means no crop-rotate-scale would be performed.
* |cros_rotate_scale_degrees| in all camera3_stream_t of a configure_streams() call must be
* identical. The HAL should return -EINVAL if the degrees are not the same for all the streams.
*/
int crop_rotate_scale_degrees;
/* reserved for future use */
void *reserved[5];
} camera3_stream_t;
/**
* camera3_stream_configuration_t:
*
* A structure of stream definitions, used by configure_streams(). This
* structure defines all the output streams and the reprocessing input
* stream for the current camera use case.
*/
typedef struct camera3_stream_configuration {
/**
* The total number of streams requested by the framework. This includes
* both input and output streams. The number of streams will be at least 1,
* and there will be at least one output-capable stream.
*/
uint32_t num_streams;
/**
* An array of camera stream pointers, defining the input/output
* configuration for the camera HAL device.
*
* At most one input-capable stream may be defined (INPUT or BIDIRECTIONAL)
* in a single configuration.
*
* At least one output-capable stream must be defined (OUTPUT or
* BIDIRECTIONAL).
*/
camera3_stream_t **streams;
/**
* >= CAMERA_DEVICE_API_VERSION_3_3:
*
* The operation mode of streams in this configuration, one of the value
* defined in camera3_stream_configuration_mode_t. The HAL can use this
* mode as an indicator to set the stream property (e.g.,
* camera3_stream->max_buffers) appropriately. For example, if the
* configuration is
* CAMERA3_STREAM_CONFIGURATION_CONSTRAINED_HIGH_SPEED_MODE, the HAL may
* want to set aside more buffers for batch mode operation (see
* android.control.availableHighSpeedVideoConfigurations for batch mode
* definition).
*
*/
uint32_t operation_mode;
/**
* >= CAMERA_DEVICE_API_VERSION_3_5:
*
* The session metadata buffer contains the initial values of
* ANDROID_REQUEST_AVAILABLE_SESSION_KEYS. This field is optional
* and camera clients can choose to ignore it, in which case it will
* be set to NULL. If parameters are present, then Hal should examine
* the parameter values and configure its internal camera pipeline
* accordingly.
*/
const camera_metadata_t *session_parameters;
} camera3_stream_configuration_t;
/**
* camera3_buffer_status_t:
*
* The current status of a single stream buffer.
*/
typedef enum camera3_buffer_status {
/**
* The buffer is in a normal state, and can be used after waiting on its
* sync fence.
*/
CAMERA3_BUFFER_STATUS_OK = 0,
/**
* The buffer does not contain valid data, and the data in it should not be
* used. The sync fence must still be waited on before reusing the buffer.
*/
CAMERA3_BUFFER_STATUS_ERROR = 1
} camera3_buffer_status_t;
/**
* camera3_stream_buffer_t:
*
* A single buffer from a camera3 stream. It includes a handle to its parent
* stream, the handle to the gralloc buffer itself, and sync fences
*
* The buffer does not specify whether it is to be used for input or output;
* that is determined by its parent stream type and how the buffer is passed to
* the HAL device.
*/
typedef struct camera3_stream_buffer {
/**
* The handle of the stream this buffer is associated with
*/
camera3_stream_t *stream;
/**
* The native handle to the buffer
*/
buffer_handle_t *buffer;
/**
* Current state of the buffer, one of the camera3_buffer_status_t
* values. The framework will not pass buffers to the HAL that are in an
* error state. In case a buffer could not be filled by the HAL, it must
* have its status set to CAMERA3_BUFFER_STATUS_ERROR when returned to the
* framework with process_capture_result().
*/
int status;
/**
* The acquire sync fence for this buffer. The HAL must wait on this fence
* fd before attempting to read from or write to this buffer.
*
* The framework may be set to -1 to indicate that no waiting is necessary
* for this buffer.
*
* When the HAL returns an output buffer to the framework with
* process_capture_result(), the acquire_fence must be set to -1. If the HAL
* never waits on the acquire_fence due to an error in filling a buffer,
* when calling process_capture_result() the HAL must set the release_fence
* of the buffer to be the acquire_fence passed to it by the framework. This
* will allow the framework to wait on the fence before reusing the buffer.
*
* For input buffers, the HAL must not change the acquire_fence field during
* the process_capture_request() call.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* When the HAL returns an input buffer to the framework with
* process_capture_result(), the acquire_fence must be set to -1. If the HAL
* never waits on input buffer acquire fence due to an error, the sync
* fences should be handled similarly to the way they are handled for output
* buffers.
*/
int acquire_fence;
/**
* The release sync fence for this buffer. The HAL must set this fence when
* returning buffers to the framework, or write -1 to indicate that no
* waiting is required for this buffer.
*
* For the output buffers, the fences must be set in the output_buffers
* array passed to process_capture_result().
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* For the input buffer, the release fence must be set by the
* process_capture_request() call.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* For the input buffer, the fences must be set in the input_buffer
* passed to process_capture_result().
*
* After signaling the release_fence for this buffer, the HAL
* should not make any further attempts to access this buffer as the
* ownership has been fully transferred back to the framework.
*
* If a fence of -1 was specified then the ownership of this buffer
* is transferred back immediately upon the call of process_capture_result.
*/
int release_fence;
} camera3_stream_buffer_t;
/**
* camera3_stream_buffer_set_t:
*
* The complete set of gralloc buffers for a stream. This structure is given to
* register_stream_buffers() to allow the camera HAL device to register/map/etc
* newly allocated stream buffers.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* Deprecated (and not used). In particular,
* register_stream_buffers is also deprecated and will never be invoked.
*
*/
typedef struct camera3_stream_buffer_set {
/**
* The stream handle for the stream these buffers belong to
*/
camera3_stream_t *stream;
/**
* The number of buffers in this stream. It is guaranteed to be at least
* stream->max_buffers.
*/
uint32_t num_buffers;
/**
* The array of gralloc buffer handles for this stream. If the stream format
* is set to HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED, the camera HAL device
* should inspect the passed-in buffers to determine any platform-private
* pixel format information.
*/
buffer_handle_t **buffers;
} camera3_stream_buffer_set_t;
/**
* camera3_jpeg_blob:
*
* Transport header for compressed JPEG buffers in output streams.
*
* To capture JPEG images, a stream is created using the pixel format
* HAL_PIXEL_FORMAT_BLOB. The buffer size for the stream is calculated by the
* framework, based on the static metadata field android.jpeg.maxSize. Since
* compressed JPEG images are of variable size, the HAL needs to include the
* final size of the compressed image using this structure inside the output
* stream buffer. The JPEG blob ID field must be set to CAMERA3_JPEG_BLOB_ID.
*
* Transport header should be at the end of the JPEG output stream buffer. That
* means the jpeg_blob_id must start at byte[buffer_size -
* sizeof(camera3_jpeg_blob)], where the buffer_size is the size of gralloc buffer.
* Any HAL using this transport header must account for it in android.jpeg.maxSize
* The JPEG data itself starts at the beginning of the buffer and should be
* jpeg_size bytes long.
*/
typedef struct camera3_jpeg_blob {
uint16_t jpeg_blob_id;
uint32_t jpeg_size;
} camera3_jpeg_blob_t;
enum {
CAMERA3_JPEG_BLOB_ID = 0x00FF
};
/**********************************************************************
*
* Message definitions for the HAL notify() callback.
*
* These definitions are used for the HAL notify callback, to signal
* asynchronous events from the HAL device to the Android framework.
*
*/
/**
* camera3_msg_type:
*
* Indicates the type of message sent, which specifies which member of the
* message union is valid.
*
*/
typedef enum camera3_msg_type {
/**
* An error has occurred. camera3_notify_msg.message.error contains the
* error information.
*/
CAMERA3_MSG_ERROR = 1,
/**
* The exposure of a given request or processing a reprocess request has
* begun. camera3_notify_msg.message.shutter contains the information
* the capture.
*/
CAMERA3_MSG_SHUTTER = 2,
/**
* Number of framework message types
*/
CAMERA3_NUM_MESSAGES
} camera3_msg_type_t;
/**
* Defined error codes for CAMERA_MSG_ERROR
*/
typedef enum camera3_error_msg_code {
/**
* A serious failure occured. No further frames or buffer streams will
* be produced by the device. Device should be treated as closed. The
* client must reopen the device to use it again. The frame_number field
* is unused.
*/
CAMERA3_MSG_ERROR_DEVICE = 1,
/**
* An error has occurred in processing a request. No output (metadata or
* buffers) will be produced for this request. The frame_number field
* specifies which request has been dropped. Subsequent requests are
* unaffected, and the device remains operational.
*/
CAMERA3_MSG_ERROR_REQUEST = 2,
/**
* An error has occurred in producing an output result metadata buffer
* for a request, but output stream buffers for it will still be
* available. Subsequent requests are unaffected, and the device remains
* operational. The frame_number field specifies the request for which
* result metadata won't be available.
*/
CAMERA3_MSG_ERROR_RESULT = 3,
/**
* An error has occurred in placing an output buffer into a stream for a
* request. The frame metadata and other buffers may still be
* available. Subsequent requests are unaffected, and the device remains
* operational. The frame_number field specifies the request for which the
* buffer was dropped, and error_stream contains a pointer to the stream
* that dropped the frame.
*/
CAMERA3_MSG_ERROR_BUFFER = 4,
/**
* Number of error types
*/
CAMERA3_MSG_NUM_ERRORS
} camera3_error_msg_code_t;
/**
* camera3_error_msg_t:
*
* Message contents for CAMERA3_MSG_ERROR
*/
typedef struct camera3_error_msg {
/**
* Frame number of the request the error applies to. 0 if the frame number
* isn't applicable to the error.
*/
uint32_t frame_number;
/**
* Pointer to the stream that had a failure. NULL if the stream isn't
* applicable to the error.
*/
camera3_stream_t *error_stream;
/**
* The code for this error; one of the CAMERA_MSG_ERROR enum values.
*/
int error_code;
} camera3_error_msg_t;
/**
* camera3_shutter_msg_t:
*
* Message contents for CAMERA3_MSG_SHUTTER
*/
typedef struct camera3_shutter_msg {
/**
* Frame number of the request that has begun exposure or reprocessing.
*/
uint32_t frame_number;
/**
* Timestamp for the start of capture. For a reprocess request, this must
* be input image's start of capture. This must match the capture result
* metadata's sensor exposure start timestamp.
*/
uint64_t timestamp;
} camera3_shutter_msg_t;
/**
* camera3_notify_msg_t:
*
* The message structure sent to camera3_callback_ops_t.notify()
*/
typedef struct camera3_notify_msg {
/**
* The message type. One of camera3_notify_msg_type, or a private extension.
*/
int type;
union {
/**
* Error message contents. Valid if type is CAMERA3_MSG_ERROR
*/
camera3_error_msg_t error;
/**
* Shutter message contents. Valid if type is CAMERA3_MSG_SHUTTER
*/
camera3_shutter_msg_t shutter;
/**
* Generic message contents. Used to ensure a minimum size for custom
* message types.
*/
uint8_t generic[32];
} message;
} camera3_notify_msg_t;
/**********************************************************************
*
* Capture request/result definitions for the HAL process_capture_request()
* method, and the process_capture_result() callback.
*
*/
/**
* camera3_request_template_t:
*
* Available template types for
* camera3_device_ops.construct_default_request_settings()
*/
typedef enum camera3_request_template {
/**
* Standard camera preview operation with 3A on auto.
*/
CAMERA3_TEMPLATE_PREVIEW = 1,
/**
* Standard camera high-quality still capture with 3A and flash on auto.
*/
CAMERA3_TEMPLATE_STILL_CAPTURE = 2,
/**
* Standard video recording plus preview with 3A on auto, torch off.
*/
CAMERA3_TEMPLATE_VIDEO_RECORD = 3,
/**
* High-quality still capture while recording video. Application will
* include preview, video record, and full-resolution YUV or JPEG streams in
* request. Must not cause stuttering on video stream. 3A on auto.
*/
CAMERA3_TEMPLATE_VIDEO_SNAPSHOT = 4,
/**
* Zero-shutter-lag mode. Application will request preview and
* full-resolution data for each frame, and reprocess it to JPEG when a
* still image is requested by user. Settings should provide highest-quality
* full-resolution images without compromising preview frame rate. 3A on
* auto.
*/
CAMERA3_TEMPLATE_ZERO_SHUTTER_LAG = 5,
/**
* A basic template for direct application control of capture
* parameters. All automatic control is disabled (auto-exposure, auto-white
* balance, auto-focus), and post-processing parameters are set to preview
* quality. The manual capture parameters (exposure, sensitivity, etc.)
* are set to reasonable defaults, but should be overridden by the
* application depending on the intended use case.
*/
CAMERA3_TEMPLATE_MANUAL = 6,
/* Total number of templates */
CAMERA3_TEMPLATE_COUNT,
/**
* First value for vendor-defined request templates
*/
CAMERA3_VENDOR_TEMPLATE_START = 0x40000000
} camera3_request_template_t;
/**
* camera3_capture_request_t:
*
* A single request for image capture/buffer reprocessing, sent to the Camera
* HAL device by the framework in process_capture_request().
*
* The request contains the settings to be used for this capture, and the set of
* output buffers to write the resulting image data in. It may optionally
* contain an input buffer, in which case the request is for reprocessing that
* input buffer instead of capturing a new image with the camera sensor. The
* capture is identified by the frame_number.
*
* In response, the camera HAL device must send a camera3_capture_result
* structure asynchronously to the framework, using the process_capture_result()
* callback.
*/
typedef struct camera3_capture_request {
/**
* The frame number is an incrementing integer set by the framework to
* uniquely identify this capture. It needs to be returned in the result
* call, and is also used to identify the request in asynchronous
* notifications sent to camera3_callback_ops_t.notify().
*/
uint32_t frame_number;
/**
* The settings buffer contains the capture and processing parameters for
* the request. As a special case, a NULL settings buffer indicates that the
* settings are identical to the most-recently submitted capture request. A
* NULL buffer cannot be used as the first submitted request after a
* configure_streams() call.
*/
const camera_metadata_t *settings;
/**
* The input stream buffer to use for this request, if any.
*
* If input_buffer is NULL, then the request is for a new capture from the
* imager. If input_buffer is valid, the request is for reprocessing the
* image contained in input_buffer.
*
* In the latter case, the HAL must set the release_fence of the
* input_buffer to a valid sync fence, or to -1 if the HAL does not support
* sync, before process_capture_request() returns.
*
* The HAL is required to wait on the acquire sync fence of the input buffer
* before accessing it.
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* Any input buffer included here will have been registered with the HAL
* through register_stream_buffers() before its inclusion in a request.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* The buffers will not have been pre-registered with the HAL.
* Subsequent requests may reuse buffers, or provide entirely new buffers.
*/
camera3_stream_buffer_t *input_buffer;
/**
* The number of output buffers for this capture request. Must be at least
* 1.
*/
uint32_t num_output_buffers;
/**
* An array of num_output_buffers stream buffers, to be filled with image
* data from this capture/reprocess. The HAL must wait on the acquire fences
* of each stream buffer before writing to them.
*
* The HAL takes ownership of the actual buffer_handle_t entries in
* output_buffers; the framework does not access them until they are
* returned in a camera3_capture_result_t.
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* All the buffers included here will have been registered with the HAL
* through register_stream_buffers() before their inclusion in a request.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* Any or all of the buffers included here may be brand new in this
* request (having never before seen by the HAL).
*/
const camera3_stream_buffer_t *output_buffers;
/**
* <= CAMERA_DEVICE_API_VERISON_3_4:
*
* Not defined and must not be accessed.
*
* >= CAMERA_DEVICE_API_VERSION_3_5:
* The number of physical camera settings to be applied. If 'num_physcam_settings'
* equals 0 or a physical device is not included, then Hal must decide the
* specific physical device settings based on the default 'settings'.
*/
uint32_t num_physcam_settings;
/**
* <= CAMERA_DEVICE_API_VERISON_3_4:
*
* Not defined and must not be accessed.
*
* >= CAMERA_DEVICE_API_VERSION_3_5:
* The physical camera ids. The array will contain 'num_physcam_settings'
* camera id strings for all physical devices that have specific settings.
* In case some id is invalid, the process capture request must fail and return
* -EINVAL.
*/
const char **physcam_id;
/**
* <= CAMERA_DEVICE_API_VERISON_3_4:
*
* Not defined and must not be accessed.
*
* >= CAMERA_DEVICE_API_VERSION_3_5:
* The capture settings for the physical cameras. The array will contain
* 'num_physcam_settings' settings for invididual physical devices. In
* case the settings at some particular index are empty, the process capture
* request must fail and return -EINVAL.
*/
const camera_metadata_t **physcam_settings;
} camera3_capture_request_t;
/**
* camera3_capture_result_t:
*
* The result of a single capture/reprocess by the camera HAL device. This is
* sent to the framework asynchronously with process_capture_result(), in
* response to a single capture request sent to the HAL with
* process_capture_request(). Multiple process_capture_result() calls may be
* performed by the HAL for each request.
*
* Each call, all with the same frame
* number, may contain some subset of the output buffers, and/or the result
* metadata. The metadata may only be provided once for a given frame number;
* all other calls must set the result metadata to NULL.
*
* The result structure contains the output metadata from this capture, and the
* set of output buffers that have been/will be filled for this capture. Each
* output buffer may come with a release sync fence that the framework will wait
* on before reading, in case the buffer has not yet been filled by the HAL.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* The metadata may be provided multiple times for a single frame number. The
* framework will accumulate together the final result set by combining each
* partial result together into the total result set.
*
* If an input buffer is given in a request, the HAL must return it in one of
* the process_capture_result calls, and the call may be to just return the input
* buffer, without metadata and output buffers; the sync fences must be handled
* the same way they are done for output buffers.
*
*
* Performance considerations:
*
* Applications will also receive these partial results immediately, so sending
* partial results is a highly recommended performance optimization to avoid
* the total pipeline latency before sending the results for what is known very
* early on in the pipeline.
*
* A typical use case might be calculating the AF state halfway through the
* pipeline; by sending the state back to the framework immediately, we get a
* 50% performance increase and perceived responsiveness of the auto-focus.
*
*/
typedef struct camera3_capture_result {
/**
* The frame number is an incrementing integer set by the framework in the
* submitted request to uniquely identify this capture. It is also used to
* identify the request in asynchronous notifications sent to
* camera3_callback_ops_t.notify().
*/
uint32_t frame_number;
/**
* The result metadata for this capture. This contains information about the
* final capture parameters, the state of the capture and post-processing
* hardware, the state of the 3A algorithms, if enabled, and the output of
* any enabled statistics units.
*
* Only one call to process_capture_result() with a given frame_number may
* include the result metadata. All other calls for the same frame_number
* must set this to NULL.
*
* If there was an error producing the result metadata, result must be an
* empty metadata buffer, and notify() must be called with ERROR_RESULT.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* Multiple calls to process_capture_result() with a given frame_number
* may include the result metadata.
*
* Partial metadata submitted should not include any metadata key returned
* in a previous partial result for a given frame. Each new partial result
* for that frame must also set a distinct partial_result value.
*
* If notify has been called with ERROR_RESULT, all further partial
* results for that frame are ignored by the framework.
*/
const camera_metadata_t *result;
/**
* The number of output buffers returned in this result structure. Must be
* less than or equal to the matching capture request's count. If this is
* less than the buffer count in the capture request, at least one more call
* to process_capture_result with the same frame_number must be made, to
* return the remaining output buffers to the framework. This may only be
* zero if the structure includes valid result metadata or an input buffer
* is returned in this result.
*/
uint32_t num_output_buffers;
/**
* The handles for the output stream buffers for this capture. They may not
* yet be filled at the time the HAL calls process_capture_result(); the
* framework will wait on the release sync fences provided by the HAL before
* reading the buffers.
*
* The HAL must set the stream buffer's release sync fence to a valid sync
* fd, or to -1 if the buffer has already been filled.
*
* If the HAL encounters an error while processing the buffer, and the
* buffer is not filled, the buffer's status field must be set to
* CAMERA3_BUFFER_STATUS_ERROR. If the HAL did not wait on the acquire fence
* before encountering the error, the acquire fence should be copied into
* the release fence, to allow the framework to wait on the fence before
* reusing the buffer.
*
* The acquire fence must be set to -1 for all output buffers. If
* num_output_buffers is zero, this may be NULL. In that case, at least one
* more process_capture_result call must be made by the HAL to provide the
* output buffers.
*
* When process_capture_result is called with a new buffer for a frame,
* all previous frames' buffers for that corresponding stream must have been
* already delivered (the fences need not have yet been signaled).
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* Gralloc buffers for a frame may be sent to framework before the
* corresponding SHUTTER-notify.
*
* Performance considerations:
*
* Buffers delivered to the framework will not be dispatched to the
* application layer until a start of exposure timestamp has been received
* via a SHUTTER notify() call. It is highly recommended to
* dispatch that call as early as possible.
*/
const camera3_stream_buffer_t *output_buffers;
/**
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* The handle for the input stream buffer for this capture. It may not
* yet be consumed at the time the HAL calls process_capture_result(); the
* framework will wait on the release sync fences provided by the HAL before
* reusing the buffer.
*
* The HAL should handle the sync fences the same way they are done for
* output_buffers.
*
* Only one input buffer is allowed to be sent per request. Similarly to
* output buffers, the ordering of returned input buffers must be
* maintained by the HAL.
*
* Performance considerations:
*
* The input buffer should be returned as early as possible. If the HAL
* supports sync fences, it can call process_capture_result to hand it back
* with sync fences being set appropriately. If the sync fences are not
* supported, the buffer can only be returned when it is consumed, which
* may take long time; the HAL may choose to copy this input buffer to make
* the buffer return sooner.
*/
const camera3_stream_buffer_t *input_buffer;
/**
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* In order to take advantage of partial results, the HAL must set the
* static metadata android.request.partialResultCount to the number of
* partial results it will send for each frame.
*
* Each new capture result with a partial result must set
* this field (partial_result) to a distinct inclusive value between
* 1 and android.request.partialResultCount.
*
* HALs not wishing to take advantage of this feature must not
* set an android.request.partialResultCount or partial_result to a value
* other than 1.
*
* This value must be set to 0 when a capture result contains buffers only
* and no metadata.
*/
uint32_t partial_result;
/**
* >= CAMERA_DEVICE_API_VERSION_3_5:
*
* Specifies the number of physical camera metadata this capture result
* contains. It must be equal to the number of physical cameras being
* requested from.
*
* If the current camera device is not a logical multi-camera, or the
* corresponding capture_request doesn't request on any physical camera,
* this field must be 0.
*/
uint32_t num_physcam_metadata;
/**
* >= CAMERA_DEVICE_API_VERSION_3_5:
*
* An array of strings containing the physical camera ids for the returned
* physical camera metadata. The length of the array is
* num_physcam_metadata.
*/
const char **physcam_ids;
/**
* >= CAMERA_DEVICE_API_VERSION_3_5:
*
* The array of physical camera metadata for the physical cameras being
* requested upon. This array should have a 1-to-1 mapping with the
* physcam_ids. The length of the array is num_physcam_metadata.
*/
const camera_metadata_t **physcam_metadata;
} camera3_capture_result_t;
/**********************************************************************
*
* Callback methods for the HAL to call into the framework.
*
* These methods are used to return metadata and image buffers for a completed
* or failed captures, and to notify the framework of asynchronous events such
* as errors.
*
* The framework will not call back into the HAL from within these callbacks,
* and these calls will not block for extended periods.
*
*/
typedef struct camera3_callback_ops {
/**
* process_capture_result:
*
* Send results from a completed capture to the framework.
* process_capture_result() may be invoked multiple times by the HAL in
* response to a single capture request. This allows, for example, the
* metadata and low-resolution buffers to be returned in one call, and
* post-processed JPEG buffers in a later call, once it is available. Each
* call must include the frame number of the request it is returning
* metadata or buffers for.
*
* A component (buffer or metadata) of the complete result may only be
* included in one process_capture_result call. A buffer for each stream,
* and the result metadata, must be returned by the HAL for each request in
* one of the process_capture_result calls, even in case of errors producing
* some of the output. A call to process_capture_result() with neither
* output buffers or result metadata is not allowed.
*
* The order of returning metadata and buffers for a single result does not
* matter, but buffers for a given stream must be returned in FIFO order. So
* the buffer for request 5 for stream A must always be returned before the
* buffer for request 6 for stream A. This also applies to the result
* metadata; the metadata for request 5 must be returned before the metadata
* for request 6.
*
* However, different streams are independent of each other, so it is
* acceptable and expected that the buffer for request 5 for stream A may be
* returned after the buffer for request 6 for stream B is. And it is
* acceptable that the result metadata for request 6 for stream B is
* returned before the buffer for request 5 for stream A is.
*
* The HAL retains ownership of result structure, which only needs to be
* valid to access during this call. The framework will copy whatever it
* needs before this call returns.
*
* The output buffers do not need to be filled yet; the framework will wait
* on the stream buffer release sync fence before reading the buffer
* data. Therefore, this method should be called by the HAL as soon as
* possible, even if some or all of the output buffers are still in
* being filled. The HAL must include valid release sync fences into each
* output_buffers stream buffer entry, or -1 if that stream buffer is
* already filled.
*
* If the result buffer cannot be constructed for a request, the HAL should
* return an empty metadata buffer, but still provide the output buffers and
* their sync fences. In addition, notify() must be called with an
* ERROR_RESULT message.
*
* If an output buffer cannot be filled, its status field must be set to
* STATUS_ERROR. In addition, notify() must be called with a ERROR_BUFFER
* message.
*
* If the entire capture has failed, then this method still needs to be
* called to return the output buffers to the framework. All the buffer
* statuses should be STATUS_ERROR, and the result metadata should be an
* empty buffer. In addition, notify() must be called with a ERROR_REQUEST
* message. In this case, individual ERROR_RESULT/ERROR_BUFFER messages
* should not be sent.
*
* Performance requirements:
*
* This is a non-blocking call. The framework will return this call in 5ms.
*
* The pipeline latency (see S7 for definition) should be less than or equal to
* 4 frame intervals, and must be less than or equal to 8 frame intervals.
*
*/
void (*process_capture_result)(const struct camera3_callback_ops *,
const camera3_capture_result_t *result);
/**
* notify:
*
* Asynchronous notification callback from the HAL, fired for various
* reasons. Only for information independent of frame capture, or that
* require specific timing. The ownership of the message structure remains
* with the HAL, and the msg only needs to be valid for the duration of this
* call.
*
* Multiple threads may call notify() simultaneously.
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* The notification for the start of exposure for a given request must be
* sent by the HAL before the first call to process_capture_result() for
* that request is made.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* Buffers delivered to the framework will not be dispatched to the
* application layer until a start of exposure timestamp (or input image's
* start of exposure timestamp for a reprocess request) has been received
* via a SHUTTER notify() call. It is highly recommended to dispatch this
* call as early as possible.
*
* ------------------------------------------------------------------------
* Performance requirements:
*
* This is a non-blocking call. The framework will return this call in 5ms.
*/
void (*notify)(const struct camera3_callback_ops *,
const camera3_notify_msg_t *msg);
} camera3_callback_ops_t;
/**********************************************************************
*
* Camera device operations
*
*/
typedef struct camera3_device_ops {
/**
* initialize:
*
* One-time initialization to pass framework callback function pointers to
* the HAL. Will be called once after a successful open() call, before any
* other functions are called on the camera3_device_ops structure.
*
* Performance requirements:
*
* This should be a non-blocking call. The HAL should return from this call
* in 5ms, and must return from this call in 10ms.
*
* Return values:
*
* 0: On successful initialization
*
* -ENODEV: If initialization fails. Only close() can be called successfully
* by the framework after this.
*/
int (*initialize)(const struct camera3_device *,
const camera3_callback_ops_t *callback_ops);
/**********************************************************************
* Stream management
*/
/**
* configure_streams:
*
* CAMERA_DEVICE_API_VERSION_3_0 only:
*
* Reset the HAL camera device processing pipeline and set up new input and
* output streams. This call replaces any existing stream configuration with
* the streams defined in the stream_list. This method will be called at
* least once after initialize() before a request is submitted with
* process_capture_request().
*
* The stream_list must contain at least one output-capable stream, and may
* not contain more than one input-capable stream.
*
* The stream_list may contain streams that are also in the currently-active
* set of streams (from the previous call to configure_stream()). These
* streams will already have valid values for usage, max_buffers, and the
* private pointer.
*
* If such a stream has already had its buffers registered,
* register_stream_buffers() will not be called again for the stream, and
* buffers from the stream can be immediately included in input requests.
*
* If the HAL needs to change the stream configuration for an existing
* stream due to the new configuration, it may rewrite the values of usage
* and/or max_buffers during the configure call.
*
* The framework will detect such a change, and will then reallocate the
* stream buffers, and call register_stream_buffers() again before using
* buffers from that stream in a request.
*
* If a currently-active stream is not included in stream_list, the HAL may
* safely remove any references to that stream. It will not be reused in a
* later configure() call by the framework, and all the gralloc buffers for
* it will be freed after the configure_streams() call returns.
*
* The stream_list structure is owned by the framework, and may not be
* accessed once this call completes. The address of an individual
* camera3_stream_t structure will remain valid for access by the HAL until
* the end of the first configure_stream() call which no longer includes
* that camera3_stream_t in the stream_list argument. The HAL may not change
* values in the stream structure outside of the private pointer, except for
* the usage and max_buffers members during the configure_streams() call
* itself.
*
* If the stream is new, the usage, max_buffer, and private pointer fields
* of the stream structure will all be set to 0. The HAL device must set
* these fields before the configure_streams() call returns. These fields
* are then used by the framework and the platform gralloc module to
* allocate the gralloc buffers for each stream.
*
* Before such a new stream can have its buffers included in a capture
* request, the framework will call register_stream_buffers() with that
* stream. However, the framework is not required to register buffers for
* _all_ streams before submitting a request. This allows for quick startup
* of (for example) a preview stream, with allocation for other streams
* happening later or concurrently.
*
* ------------------------------------------------------------------------
* CAMERA_DEVICE_API_VERSION_3_1 only:
*
* Reset the HAL camera device processing pipeline and set up new input and
* output streams. This call replaces any existing stream configuration with
* the streams defined in the stream_list. This method will be called at
* least once after initialize() before a request is submitted with
* process_capture_request().
*
* The stream_list must contain at least one output-capable stream, and may
* not contain more than one input-capable stream.
*
* The stream_list may contain streams that are also in the currently-active
* set of streams (from the previous call to configure_stream()). These
* streams will already have valid values for usage, max_buffers, and the
* private pointer.
*
* If such a stream has already had its buffers registered,
* register_stream_buffers() will not be called again for the stream, and
* buffers from the stream can be immediately included in input requests.
*
* If the HAL needs to change the stream configuration for an existing
* stream due to the new configuration, it may rewrite the values of usage
* and/or max_buffers during the configure call.
*
* The framework will detect such a change, and will then reallocate the
* stream buffers, and call register_stream_buffers() again before using
* buffers from that stream in a request.
*
* If a currently-active stream is not included in stream_list, the HAL may
* safely remove any references to that stream. It will not be reused in a
* later configure() call by the framework, and all the gralloc buffers for
* it will be freed after the configure_streams() call returns.
*
* The stream_list structure is owned by the framework, and may not be
* accessed once this call completes. The address of an individual
* camera3_stream_t structure will remain valid for access by the HAL until
* the end of the first configure_stream() call which no longer includes
* that camera3_stream_t in the stream_list argument. The HAL may not change
* values in the stream structure outside of the private pointer, except for
* the usage and max_buffers members during the configure_streams() call
* itself.
*
* If the stream is new, max_buffer, and private pointer fields of the
* stream structure will all be set to 0. The usage will be set to the
* consumer usage flags. The HAL device must set these fields before the
* configure_streams() call returns. These fields are then used by the
* framework and the platform gralloc module to allocate the gralloc
* buffers for each stream.
*
* Before such a new stream can have its buffers included in a capture
* request, the framework will call register_stream_buffers() with that
* stream. However, the framework is not required to register buffers for
* _all_ streams before submitting a request. This allows for quick startup
* of (for example) a preview stream, with allocation for other streams
* happening later or concurrently.
*
* ------------------------------------------------------------------------
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* Reset the HAL camera device processing pipeline and set up new input and
* output streams. This call replaces any existing stream configuration with
* the streams defined in the stream_list. This method will be called at
* least once after initialize() before a request is submitted with
* process_capture_request().
*
* The stream_list must contain at least one output-capable stream, and may
* not contain more than one input-capable stream.
*
* The stream_list may contain streams that are also in the currently-active
* set of streams (from the previous call to configure_stream()). These
* streams will already have valid values for usage, max_buffers, and the
* private pointer.
*
* If the HAL needs to change the stream configuration for an existing
* stream due to the new configuration, it may rewrite the values of usage
* and/or max_buffers during the configure call.
*
* The framework will detect such a change, and may then reallocate the
* stream buffers before using buffers from that stream in a request.
*
* If a currently-active stream is not included in stream_list, the HAL may
* safely remove any references to that stream. It will not be reused in a
* later configure() call by the framework, and all the gralloc buffers for
* it will be freed after the configure_streams() call returns.
*
* The stream_list structure is owned by the framework, and may not be
* accessed once this call completes. The address of an individual
* camera3_stream_t structure will remain valid for access by the HAL until
* the end of the first configure_stream() call which no longer includes
* that camera3_stream_t in the stream_list argument. The HAL may not change
* values in the stream structure outside of the private pointer, except for
* the usage and max_buffers members during the configure_streams() call
* itself.
*
* If the stream is new, max_buffer, and private pointer fields of the
* stream structure will all be set to 0. The usage will be set to the
* consumer usage flags. The HAL device must set these fields before the
* configure_streams() call returns. These fields are then used by the
* framework and the platform gralloc module to allocate the gralloc
* buffers for each stream.
*
* Newly allocated buffers may be included in a capture request at any time
* by the framework. Once a gralloc buffer is returned to the framework
* with process_capture_result (and its respective release_fence has been
* signaled) the framework may free or reuse it at any time.
*
* ------------------------------------------------------------------------
*
* Preconditions:
*
* The framework will only call this method when no captures are being
* processed. That is, all results have been returned to the framework, and
* all in-flight input and output buffers have been returned and their
* release sync fences have been signaled by the HAL. The framework will not
* submit new requests for capture while the configure_streams() call is
* underway.
*
* Postconditions:
*
* The HAL device must configure itself to provide maximum possible output
* frame rate given the sizes and formats of the output streams, as
* documented in the camera device's static metadata.
*
* Performance requirements:
*
* This call is expected to be heavyweight and possibly take several hundred
* milliseconds to complete, since it may require resetting and
* reconfiguring the image sensor and the camera processing pipeline.
* Nevertheless, the HAL device should attempt to minimize the
* reconfiguration delay to minimize the user-visible pauses during
* application operational mode changes (such as switching from still
* capture to video recording).
*
* The HAL should return from this call in 500ms, and must return from this
* call in 1000ms.
*
* Return values:
*
* 0: On successful stream configuration
*
* -EINVAL: If the requested stream configuration is invalid. Some examples
* of invalid stream configurations include:
*
* - Including more than 1 input-capable stream (INPUT or
* BIDIRECTIONAL)
*
* - Not including any output-capable streams (OUTPUT or
* BIDIRECTIONAL)
*
* - Including streams with unsupported formats, or an unsupported
* size for that format.
*
* - Including too many output streams of a certain format.
*
* - Unsupported rotation configuration (only applies to
* devices with version >= CAMERA_DEVICE_API_VERSION_3_3)
*
* - Stream sizes/formats don't satisfy the
* camera3_stream_configuration_t->operation_mode requirements for non-NORMAL mode,
* or the requested operation_mode is not supported by the HAL.
* (only applies to devices with version >= CAMERA_DEVICE_API_VERSION_3_3)
*
* Note that the framework submitting an invalid stream
* configuration is not normal operation, since stream
* configurations are checked before configure. An invalid
* configuration means that a bug exists in the framework code, or
* there is a mismatch between the HAL's static metadata and the
* requirements on streams.
*
* -ENODEV: If there has been a fatal error and the device is no longer
* operational. Only close() can be called successfully by the
* framework after this error is returned.
*/
int (*configure_streams)(const struct camera3_device *,
camera3_stream_configuration_t *stream_list);
/**
* register_stream_buffers:
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* DEPRECATED. This will not be called and must be set to NULL.
*
* <= CAMERA_DEVICE_API_VERSION_3_1:
*
* Register buffers for a given stream with the HAL device. This method is
* called by the framework after a new stream is defined by
* configure_streams, and before buffers from that stream are included in a
* capture request. If the same stream is listed in a subsequent
* configure_streams() call, register_stream_buffers will _not_ be called
* again for that stream.
*
* The framework does not need to register buffers for all configured
* streams before it submits the first capture request. This allows quick
* startup for preview (or similar use cases) while other streams are still
* being allocated.
*
* This method is intended to allow the HAL device to map or otherwise
* prepare the buffers for later use. The buffers passed in will already be
* locked for use. At the end of the call, all the buffers must be ready to
* be returned to the stream. The buffer_set argument is only valid for the
* duration of this call.
*
* If the stream format was set to HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED,
* the camera HAL should inspect the passed-in buffers here to determine any
* platform-private pixel format information.
*
* Performance requirements:
*
* This should be a non-blocking call. The HAL should return from this call
* in 1ms, and must return from this call in 5ms.
*
* Return values:
*
* 0: On successful registration of the new stream buffers
*
* -EINVAL: If the stream_buffer_set does not refer to a valid active
* stream, or if the buffers array is invalid.
*
* -ENOMEM: If there was a failure in registering the buffers. The framework
* must consider all the stream buffers to be unregistered, and can
* try to register again later.
*
* -ENODEV: If there is a fatal error, and the device is no longer
* operational. Only close() can be called successfully by the
* framework after this error is returned.
*/
int (*register_stream_buffers)(const struct camera3_device *,
const camera3_stream_buffer_set_t *buffer_set);
/**********************************************************************
* Request creation and submission
*/
/**
* construct_default_request_settings:
*
* Create capture settings for standard camera use cases.
*
* The device must return a settings buffer that is configured to meet the
* requested use case, which must be one of the CAMERA3_TEMPLATE_*
* enums. All request control fields must be included.
*
* The HAL retains ownership of this structure, but the pointer to the
* structure must be valid until the device is closed. The framework and the
* HAL may not modify the buffer once it is returned by this call. The same
* buffer may be returned for subsequent calls for the same template, or for
* other templates.
*
* Performance requirements:
*
* This should be a non-blocking call. The HAL should return from this call
* in 1ms, and must return from this call in 5ms.
*
* Return values:
*
* Valid metadata: On successful creation of a default settings
* buffer.
*
* NULL: In case of a fatal error. After this is returned, only
* the close() method can be called successfully by the
* framework.
*/
const camera_metadata_t* (*construct_default_request_settings)(
const struct camera3_device *,
int type);
/**
* process_capture_request:
*
* Send a new capture request to the HAL. The HAL should not return from
* this call until it is ready to accept the next request to process. Only
* one call to process_capture_request() will be made at a time by the
* framework, and the calls will all be from the same thread. The next call
* to process_capture_request() will be made as soon as a new request and
* its associated buffers are available. In a normal preview scenario, this
* means the function will be called again by the framework almost
* instantly.
*
* The actual request processing is asynchronous, with the results of
* capture being returned by the HAL through the process_capture_result()
* call. This call requires the result metadata to be available, but output
* buffers may simply provide sync fences to wait on. Multiple requests are
* expected to be in flight at once, to maintain full output frame rate.
*
* The framework retains ownership of the request structure. It is only
* guaranteed to be valid during this call. The HAL device must make copies
* of the information it needs to retain for the capture processing. The HAL
* is responsible for waiting on and closing the buffers' fences and
* returning the buffer handles to the framework.
*
* The HAL must write the file descriptor for the input buffer's release
* sync fence into input_buffer->release_fence, if input_buffer is not
* NULL. If the HAL returns -1 for the input buffer release sync fence, the
* framework is free to immediately reuse the input buffer. Otherwise, the
* framework will wait on the sync fence before refilling and reusing the
* input buffer.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
*
* The input/output buffers provided by the framework in each request
* may be brand new (having never before seen by the HAL).
*
* ------------------------------------------------------------------------
* Performance considerations:
*
* Handling a new buffer should be extremely lightweight and there should be
* no frame rate degradation or frame jitter introduced.
*
* This call must return fast enough to ensure that the requested frame
* rate can be sustained, especially for streaming cases (post-processing
* quality settings set to FAST). The HAL should return this call in 1
* frame interval, and must return from this call in 4 frame intervals.
*
* Return values:
*
* 0: On a successful start to processing the capture request
*
* -EINVAL: If the input is malformed (the settings are NULL when not
* allowed, invalid physical camera settings,
* there are 0 output buffers, etc) and capture processing
* cannot start. Failures during request processing should be
* handled by calling camera3_callback_ops_t.notify(). In case of
* this error, the framework will retain responsibility for the
* stream buffers' fences and the buffer handles; the HAL should
* not close the fences or return these buffers with
* process_capture_result.
*
* -ENODEV: If the camera device has encountered a serious error. After this
* error is returned, only the close() method can be successfully
* called by the framework.
*
*/
int (*process_capture_request)(const struct camera3_device *,
camera3_capture_request_t *request);
/**********************************************************************
* Miscellaneous methods
*/
/**
* get_metadata_vendor_tag_ops:
*
* Get methods to query for vendor extension metadata tag information. The
* HAL should fill in all the vendor tag operation methods, or leave ops
* unchanged if no vendor tags are defined.
*
* The definition of vendor_tag_query_ops_t can be found in
* system/media/camera/include/system/camera_metadata.h.
*
* >= CAMERA_DEVICE_API_VERSION_3_2:
* DEPRECATED. This function has been deprecated and should be set to
* NULL by the HAL. Please implement get_vendor_tag_ops in camera_common.h
* instead.
*/
void (*get_metadata_vendor_tag_ops)(const struct camera3_device*,
vendor_tag_query_ops_t* ops);
/**
* dump:
*
* Print out debugging state for the camera device. This will be called by
* the framework when the camera service is asked for a debug dump, which
* happens when using the dumpsys tool, or when capturing a bugreport.
*
* The passed-in file descriptor can be used to write debugging text using
* dprintf() or write(). The text should be in ASCII encoding only.
*
* Performance requirements:
*
* This must be a non-blocking call. The HAL should return from this call
* in 1ms, must return from this call in 10ms. This call must avoid
* deadlocks, as it may be called at any point during camera operation.
* Any synchronization primitives used (such as mutex locks or semaphores)
* should be acquired with a timeout.
*/
void (*dump)(const struct camera3_device *, int fd);
/**
* flush:
*
* Flush all currently in-process captures and all buffers in the pipeline
* on the given device. The framework will use this to dump all state as
* quickly as possible in order to prepare for a configure_streams() call.
*
* No buffers are required to be successfully returned, so every buffer
* held at the time of flush() (whether successfully filled or not) may be
* returned with CAMERA3_BUFFER_STATUS_ERROR. Note the HAL is still allowed
* to return valid (CAMERA3_BUFFER_STATUS_OK) buffers during this call,
* provided they are successfully filled.
*
* All requests currently in the HAL are expected to be returned as soon as
* possible. Not-in-process requests should return errors immediately. Any
* interruptible hardware blocks should be stopped, and any uninterruptible
* blocks should be waited on.
*
* flush() may be called concurrently to process_capture_request(), with the expectation that
* process_capture_request will return quickly and the request submitted in that
* process_capture_request call is treated like all other in-flight requests. Due to
* concurrency issues, it is possible that from the HAL's point of view, a
* process_capture_request() call may be started after flush has been invoked but has not
* returned yet. If such a call happens before flush() returns, the HAL should treat the new
* capture request like other in-flight pending requests (see #4 below).
*
* More specifically, the HAL must follow below requirements for various cases:
*
* 1. For captures that are too late for the HAL to cancel/stop, and will be
* completed normally by the HAL; i.e. the HAL can send shutter/notify and
* process_capture_result and buffers as normal.
*
* 2. For pending requests that have not done any processing, the HAL must call notify
* CAMERA3_MSG_ERROR_REQUEST, and return all the output buffers with
* process_capture_result in the error state (CAMERA3_BUFFER_STATUS_ERROR).
* The HAL must not place the release fence into an error state, instead,
* the release fences must be set to the acquire fences passed by the framework,
* or -1 if they have been waited on by the HAL already. This is also the path
* to follow for any captures for which the HAL already called notify() with
* CAMERA3_MSG_SHUTTER but won't be producing any metadata/valid buffers for.
* After CAMERA3_MSG_ERROR_REQUEST, for a given frame, only process_capture_results with
* buffers in CAMERA3_BUFFER_STATUS_ERROR are allowed. No further notifys or
* process_capture_result with non-null metadata is allowed.
*
* 3. For partially completed pending requests that will not have all the output
* buffers or perhaps missing metadata, the HAL should follow below:
*
* 3.1. Call notify with CAMERA3_MSG_ERROR_RESULT if some of the expected result
* metadata (i.e. one or more partial metadata) won't be available for the capture.
*
* 3.2. Call notify with CAMERA3_MSG_ERROR_BUFFER for every buffer that won't
* be produced for the capture.
*
* 3.3 Call notify with CAMERA3_MSG_SHUTTER with the capture timestamp before
* any buffers/metadata are returned with process_capture_result.
*
* 3.4 For captures that will produce some results, the HAL must not call
* CAMERA3_MSG_ERROR_REQUEST, since that indicates complete failure.
*
* 3.5. Valid buffers/metadata should be passed to the framework as normal.
*
* 3.6. Failed buffers should be returned to the framework as described for case 2.
* But failed buffers do not have to follow the strict ordering valid buffers do,
* and may be out-of-order with respect to valid buffers. For example, if buffers
* A, B, C, D, E are sent, D and E are failed, then A, E, B, D, C is an acceptable
* return order.
*
* 3.7. For fully-missing metadata, calling CAMERA3_MSG_ERROR_RESULT is sufficient, no
* need to call process_capture_result with NULL metadata or equivalent.
*
* 4. If a flush() is invoked while a process_capture_request() invocation is active, that
* process call should return as soon as possible. In addition, if a process_capture_request()
* call is made after flush() has been invoked but before flush() has returned, the
* capture request provided by the late process_capture_request call should be treated like
* a pending request in case #2 above.
*
* flush() should only return when there are no more outstanding buffers or
* requests left in the HAL. The framework may call configure_streams (as
* the HAL state is now quiesced) or may issue new requests.
*
* Note that it's sufficient to only support fully-succeeded and fully-failed result cases.
* However, it is highly desirable to support the partial failure cases as well, as it
* could help improve the flush call overall performance.
*
* Performance requirements:
*
* The HAL should return from this call in 100ms, and must return from this
* call in 1000ms. And this call must not be blocked longer than pipeline
* latency (see S7 for definition).
*
* Version information:
*
* only available if device version >= CAMERA_DEVICE_API_VERSION_3_1.
*
* Return values:
*
* 0: On a successful flush of the camera HAL.
*
* -EINVAL: If the input is malformed (the device is not valid).
*
* -ENODEV: If the camera device has encountered a serious error. After this
* error is returned, only the close() method can be successfully
* called by the framework.
*/
int (*flush)(const struct camera3_device *);
/* reserved for future use */
void *reserved[8];
} camera3_device_ops_t;
/**********************************************************************
*
* Camera device definition
*
*/
typedef struct camera3_device {
/**
* common.version must equal CAMERA_DEVICE_API_VERSION_3_0 to identify this
* device as implementing version 3.0 of the camera device HAL.
*
* Performance requirements:
*
* Camera open (common.module->common.methods->open) should return in 200ms, and must return
* in 500ms.
* Camera close (common.close) should return in 200ms, and must return in 500ms.
*
*/
hw_device_t common;
camera3_device_ops_t *ops;
void *priv;
} camera3_device_t;
__END_DECLS
#endif /* #ifdef ANDROID_INCLUDE_CAMERA3_H */