Video Capture: extract storage info from pixel format in VideoCaptureFormat.

media/video/capture/video_capture_device.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // VideoCaptureDevice is the abstract base class for realizing video capture
 // device support in Chromium. It provides the interface for OS dependent
 // implementations.
 // The class is created and functions are invoked on a thread owned by
 // VideoCaptureManager. Capturing is done on other threads, depending on the OS
 // specific implementation.
@@ skipping 228 matching lines @@
     // The returned Buffer will always be allocated with a memory size suitable
     // for holding a packed video frame with pixels of |format| format, of
     // |dimensions| frame dimensions. It is permissible for |dimensions| to be
     // zero; in which case the returned Buffer does not guarantee memory
     // backing, but functions as a reservation for external input for the
     // purposes of buffer throttling.
     //
     // The output buffer stays reserved and mapped for use until the Buffer
     // object is destroyed or returned.
     virtual scoped_ptr<Buffer> ReserveOutputBuffer(
-        media::VideoPixelFormat format,
-        const gfx::Size& dimensions) = 0;
+        const VideoCaptureFormat& frame_format) = 0;

[miu, 2015/06/13 00:41:37]

Hmm...We talked about this in a similar change a few months back, where: 1) the
frame_rate field of VideoCaptureFormat is always unused; and 2) you're burdening
all client code with creating a VideoCaptureFormat struct to make a method call.
 Even with this new, 3rd argument I still feel you should just pass 3 args
instead of the struct.  We can revisit this when it becomes 4+ args.  ;-)

[mcasas, 2015/06/16 23:14:01]

Done.

 
     // Captured new video data, held in |frame| or |buffer|, respectively for
     // OnIncomingCapturedVideoFrame() and  OnIncomingCapturedBuffer().
     //
     // In both cases, as the frame is backed by a reservation returned by
     // ReserveOutputBuffer(), delivery is guaranteed and will require no
     // additional copies in the browser process.
     virtual void OnIncomingCapturedBuffer(
         scoped_ptr<Buffer> buffer,
         const VideoCaptureFormat& frame_format,
@@ skipping 37 matching lines @@
   int GetPowerLineFrequencyForLocation() const;
 
  protected:
   static const int kPowerLine50Hz = 50;
   static const int kPowerLine60Hz = 60;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_VIDEO_CAPTURE_VIDEO_CAPTURE_DEVICE_H_