media: Introduce Y8 and Y16 video pixel format

media/renderers/skcanvas_video_renderer.cc

 // 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.
 
 #include "media/renderers/skcanvas_video_renderer.h"
 
 #include <limits>
 
 #include "base/macros.h"
 #include "gpu/GLES2/gl2extchromium.h"
@@ skipping 592 matching lines @@
     case PIXEL_FORMAT_NV12:
     case PIXEL_FORMAT_NV21:
     case PIXEL_FORMAT_UYVY:
     case PIXEL_FORMAT_YUY2:
     case PIXEL_FORMAT_ARGB:
     case PIXEL_FORMAT_XRGB:
     case PIXEL_FORMAT_RGB24:
     case PIXEL_FORMAT_RGB32:
     case PIXEL_FORMAT_MJPEG:
     case PIXEL_FORMAT_MT21:
+    case PIXEL_FORMAT_Y8:

[fbarchard1, 2016/09/20 21:52:24]

Y8 is supported by libyuv if you want to add the converter to ARGB.
Use either I400ToARGB or J400ToARGB depending if you want bt601 constrained
range of 16 to 240, or JPeg full range 601 coefficients.

[dshwang, 2016/09/21 09:00:00]

Thank you for suggestion. My plan is to draw Y8 directly by compositor renderer.
If the conversion is necessary, we will add J400ToARGB conversion in
https://codereview.chromium.org/2121043002/ when we actually support Y8
rendering.

[fbarchard1, 2016/09/22 21:06:57]

Add a TODO to that effect?
Not all drivers support Y8 or Y16.  Some would have P8 that could be used as a
fallback.  But the software conversion is trivial/fast.

[dshwang, 2016/09/26 13:02:22]

Done. Added the comment you explained.

+    case PIXEL_FORMAT_Y16:
     case PIXEL_FORMAT_UNKNOWN:
       NOTREACHED();
   }
 }
 
 // static
 void SkCanvasVideoRenderer::CopyVideoFrameSingleTextureToGLTexture(
     gpu::gles2::GLES2Interface* gl,
     VideoFrame* video_frame,
     unsigned int texture,
@@ skipping 131 matching lines @@
     if (!last_image_)  // Couldn't create the SkImage.
       return false;
     last_timestamp_ = video_frame->timestamp();
   }
   last_image_deleting_timer_.Reset();
   DCHECK(!!last_image_);
   return true;
 }
 
 }  // namespace media