chromecast/public/media/video_pipeline_device.h

   1 // Copyright 2014 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 CHROMECAST_PUBLIC_MEDIA_VIDEO_PIPELINE_DEVICE_H_
   6 #define CHROMECAST_PUBLIC_MEDIA_VIDEO_PIPELINE_DEVICE_H_
   7
   8 #include "media_component_device.h"
   9
  10 namespace chromecast {
  11 struct Size;
  12
  13 namespace media {
  14 struct VideoConfig;
  15
  16 // Interface for platform-specific video pipeline backend.
  17 // See comments on MediaComponentDevice.
  18 //
  19 // Notes:
  20 // - Like a regular MediaComponentDevice, frames are possibly rendered only
  21 //   in the kRunning state.
  22 //   However, the first frame must be rendered regardless of the clock state:
  23 //   - no synchronization needed to display the first frame,
  24 //   - the clock rate has no impact on the presentation of the first frame.
  25 class VideoPipelineDevice : public MediaComponentDevice {
  26  public:
  27   // Callback interface for natural size of video changing.
  28   class VideoClient {
  29    public:
  30     virtual ~VideoClient() {}
  31     virtual void OnNaturalSizeChanged(const Size& size) = 0;
  32   };
  33
  34   ~VideoPipelineDevice() override {}
  35
  36   // Registers |client| as the video specific event handler.
  37   // Implementation takes ownership of |client|.
  38   virtual void SetVideoClient(VideoClient* client) = 0;
  39
  40   // Provides the video configuration.
  41   // Called before switching from |kStateUninitialized| to |kStateIdle|.
  42   // Afterwards, this can be invoked any time the configuration changes.
  43   // Returns true if the configuration is a supported configuration.
  44   virtual bool SetConfig(const VideoConfig& config) = 0;
  45 };
  46
  47 }  // namespace media
  48 }  // namespace chromecast
  49
  50 #endif  // CHROMECAST_MEDIA_CMA_BACKEND_VIDEO_PIPELINE_DEVICE_H_