content/browser/renderer_host/media/video_capture_device_client.h

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_DEVICE_CLIENT_H_
   6 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_DEVICE_CLIENT_H_
   7
   8 #include "base/memory/ref_counted.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "base/memory/weak_ptr.h"
  11 #include "content/common/content_export.h"
  12 #include "media/capture/video/video_capture_device.h"
  13
  14 namespace content {
  15 class VideoCaptureBufferPool;
  16 class VideoCaptureController;
  17 class VideoCaptureGpuJpegDecoder;
  18
  19 // Receives events from the VideoCaptureDevice and posts them to a |controller_|
  20 // on the IO thread. An instance of this class may safely outlive its target
  21 // VideoCaptureController. This is a shallow class meant to convert incoming
  22 // frames and holds no significant state.
  23 //
  24 // Methods of this class may be called from any thread, and in practice will
  25 // often be called on some auxiliary thread depending on the platform and the
  26 // device type; including, for example, the DirectShow thread on Windows, the
  27 // v4l2_thread on Linux, and the UI thread for tab capture.
  28 //
  29 // It has an internal ref counted TextureWrapHelper class used to wrap incoming
  30 // GpuMemoryBuffers into Texture backed VideoFrames. This class creates and
  31 // manages the necessary entities to interact with the GPU process, notably an
  32 // offscreen Context to avoid janking the UI thread.
  33 class CONTENT_EXPORT VideoCaptureDeviceClient
  34     : public media::VideoCaptureDevice::Client,
  35       public base::SupportsWeakPtr<VideoCaptureDeviceClient> {
  36  public:
  37   VideoCaptureDeviceClient(
  38       const base::WeakPtr<VideoCaptureController>& controller,
  39       const scoped_refptr<VideoCaptureBufferPool>& buffer_pool,
  40       const scoped_refptr<base::SingleThreadTaskRunner>& capture_task_runner);
  41   ~VideoCaptureDeviceClient() override;
  42
  43   // VideoCaptureDevice::Client implementation.
  44   void OnIncomingCapturedData(const uint8* data,
  45                               int length,
  46                               const media::VideoCaptureFormat& frame_format,
  47                               int rotation,
  48                               const base::TimeTicks& timestamp) override;
  49   void OnIncomingCapturedYuvData(const uint8* y_data,
  50                                  const uint8* u_data,
  51                                  const uint8* v_data,
  52                                  size_t y_stride,
  53                                  size_t u_stride,
  54                                  size_t v_stride,
  55                                  const media::VideoCaptureFormat& frame_format,
  56                                  int clockwise_rotation,
  57                                  const base::TimeTicks& timestamp) override;
  58   scoped_ptr<Buffer> ReserveOutputBuffer(
  59       const gfx::Size& dimensions,
  60       media::VideoPixelFormat format,
  61       media::VideoPixelStorage storage) override;
  62   void OnIncomingCapturedBuffer(scoped_ptr<Buffer> buffer,
  63                                 const media::VideoCaptureFormat& frame_format,
  64                                 const base::TimeTicks& timestamp) override;
  65   void OnIncomingCapturedVideoFrame(
  66       scoped_ptr<Buffer> buffer,
  67       const scoped_refptr<media::VideoFrame>& frame,
  68       const base::TimeTicks& timestamp) override;
  69   void OnError(const std::string& reason) override;
  70   void OnLog(const std::string& message) override;
  71   double GetBufferPoolUtilization() const override;
  72
  73  private:
  74   // Reserve output buffer into which I420 contents can be copied directly.
  75   // The dimensions of the frame is described by |dimensions|, and requested
  76   // output buffer format is specified by |storage|. The reserved output buffer
  77   // is returned; and the pointer to Y plane is stored at [y_plane_data], U
  78   // plane is stored at [u_plane_data], V plane is stored at [v_plane_data].
  79   // Returns an nullptr if allocation fails.
  80   //
  81   // When requested |storage| is PIXEL_STORAGE_CPU, a single shared memory
  82   // chunk is reserved; whereas for PIXEL_STORAGE_GPUMEMORYBUFFER, three
  83   // GpuMemoryBuffers in R_8 format representing I420 planes are reserved. The
  84   // output buffers stay reserved and mapped for use until the Buffer objects
  85   // are destroyed or returned.
  86   scoped_ptr<Buffer> ReserveI420OutputBuffer(const gfx::Size& dimensions,
  87                                              media::VideoPixelStorage storage,
  88                                              uint8** y_plane_data,
  89                                              uint8** u_plane_data,
  90                                              uint8** v_plane_data);
  91
  92   // The controller to which we post events.
  93   const base::WeakPtr<VideoCaptureController> controller_;
  94
  95   // Hardware JPEG decoder.
  96   scoped_ptr<VideoCaptureGpuJpegDecoder> external_jpeg_decoder_;
  97
  98   // Whether |external_jpeg_decoder_| has been initialized.
  99   bool external_jpeg_decoder_initialized_;
 100
 101   // The pool of shared-memory buffers used for capturing.
 102   const scoped_refptr<VideoCaptureBufferPool> buffer_pool_;
 103
 104   // Indication to the Client to copy-transform the incoming data into
 105   // GpuMemoryBuffers.
 106   const bool use_gpu_memory_buffers_;
 107
 108   // Internal delegate for GpuMemoryBuffer-into-VideoFrame wrapping.
 109   class TextureWrapHelper;
 110   scoped_refptr<TextureWrapHelper> texture_wrap_helper_;
 111   // Reference to Capture Thread task runner, where |texture_wrap_helper_|
 112   // lives.
 113   const scoped_refptr<base::SingleThreadTaskRunner> capture_task_runner_;
 114
 115   media::VideoPixelFormat last_captured_pixel_format_;
 116
 117   DISALLOW_COPY_AND_ASSIGN(VideoCaptureDeviceClient);
 118 };
 119
 120
 121 }  // namespace content
 122
 123 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_DEVICE_CLIENT_H_