| // Copyright (c) 2010 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef MEDIA_V4L2_DEVICE_H_ |
| #define MEDIA_V4L2_DEVICE_H_ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <linux/videodev2.h> |
| #include <malloc.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/ioctl.h> |
| #include <sys/mman.h> |
| #include <unistd.h> |
| |
| class V4L2Device { |
| public: |
| enum IOMethod { |
| IO_METHOD_READ, |
| IO_METHOD_MMAP, |
| IO_METHOD_USERPTR, |
| }; |
| |
| struct Buffer { |
| void* start; |
| size_t length; |
| }; |
| |
| V4L2Device(const char* dev_name, |
| IOMethod io, |
| uint32_t buffers); |
| virtual ~V4L2Device() {} |
| |
| virtual bool OpenDevice(); |
| virtual void CloseDevice(); |
| virtual bool InitDevice(uint32_t width, |
| uint32_t height, |
| uint32_t pixfmt, |
| uint32_t fps); |
| virtual bool UninitDevice(); |
| virtual bool StartCapture(); |
| virtual bool StopCapture(); |
| virtual bool Run(uint32_t frames, uint32_t time_in_sec = 0); |
| |
| // Helper methods. |
| bool EnumInput(); |
| bool EnumStandard(); |
| bool EnumControl(bool show_menu = true); |
| bool EnumControlMenu(const v4l2_queryctrl& query_ctrl); |
| bool EnumFormat(uint32_t* num_formats, bool show_fmt = true); |
| bool EnumFrameSize(uint32_t pixfmt, bool show_frmsize = true); |
| |
| bool QueryControl(uint32_t id, v4l2_queryctrl* ctrl); |
| bool SetControl(uint32_t id, int32_t value); |
| bool ProbeCaps(v4l2_capability* cap, bool show_caps = false); |
| bool GetCropCap(v4l2_cropcap* cropcap); |
| bool GetCrop(v4l2_crop* crop); |
| bool SetCrop(v4l2_crop* crop); |
| bool GetParam(v4l2_streamparm* param); |
| bool SetParam(v4l2_streamparm* param); |
| bool SetFrameRate(uint32_t fps); |
| uint32_t GetPixelFormat(uint32_t index); |
| uint32_t GetFrameRate(); |
| bool Stop(); |
| |
| // Getter. |
| int32_t GetActualWidth() { |
| return width_; |
| } |
| |
| int32_t GetActualHeight() { |
| return height_; |
| } |
| |
| v4l2_format& GetActualPixelFormat() { |
| return pixfmt_; |
| } |
| |
| static uint32_t MapFourCC(const char* fourcc); |
| |
| virtual void ProcessImage(const void* p); |
| |
| private: |
| int32_t DoIoctl(int32_t request, void* arg); |
| int32_t ReadOneFrame(); |
| bool InitReadIO(uint32_t buffer_size); |
| bool InitMmapIO(); |
| bool InitUserPtrIO(uint32_t buffer_size); |
| bool AllocateBuffer(uint32_t buffer_count); |
| bool FreeBuffer(); |
| uint64_t Now(); |
| |
| const char* dev_name_; |
| IOMethod io_; |
| int32_t fd_; |
| Buffer* v4l2_buffers_; |
| uint32_t num_buffers_; // Actual buffers allocation. |
| uint32_t min_buffers_; // Minimum buffers requirement. |
| bool stopped_; |
| |
| // Valid only after |InitDevice()|. |
| uint32_t width_, height_; |
| v4l2_format pixfmt_; |
| }; |
| |
| #endif // MEDIA_V4L2_DEVICE_H_ |
| |