Extend media::VideoFrame to wrap CVPixelBuffer on OS X and iOS.

media/base/video_frame.cc

Index: media/base/video_frame.cc
diff --git a/media/base/video_frame.cc b/media/base/video_frame.cc
index 6b3427db1aa936c1707b507f13e1070ed33710b0..c77dc1348b69258fef99544846521374ddf1f290 100644
--- a/media/base/video_frame.cc
+++ b/media/base/video_frame.cc
@@ -278,6 +278,51 @@ scoped_refptr<VideoFrame> VideoFrame::WrapExternalDmabufs(
 }
 #endif
 
+#if defined(OS_MACOSX)
+// static
+scoped_refptr<VideoFrame> VideoFrame::WrapCVPixelBuffer(
+    CVPixelBufferRef cv_pixel_buffer,
+    base::TimeDelta timestamp) {
+  DCHECK(cv_pixel_buffer);
+  DCHECK(CFGetTypeID(cv_pixel_buffer) == CVPixelBufferGetTypeID());
+
+  OSType cv_format = CVPixelBufferGetPixelFormatType(cv_pixel_buffer);
+  Format format;
+  // There are very few compatible CV pixel formats, so just check each.
+  if (cv_format == kCVPixelFormatType_420YpCbCr8Planar) {
+    format = Format::I420;
+  } else if (cv_format == kCVPixelFormatType_444YpCbCr8) {
+    format = Format::YV24;
+  } else if (cv_format == '420v') {
+    // TODO(jfroy): Use kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange when the

[miu, 2014/08/25 18:39:35]

I've seen others solve this problem by using #ifdefs to define constants at the
top of the file based on the SDK version.  Meaning, when the SDK is too old, we
define the constants ourselves using those found in the newer SDK.  Example:

https://code.google.com/p/chromium/codesearch#chromium/src/base/mac/sdk_forwa...

[Robert Sesek, 2014/08/25 18:42:07]

There was already back-and-forth about this on the review. This is fine.

+    // minimum OS X and iOS SDKs permits it.
+    format = Format::NV12;
+  } else {
+    DLOG(ERROR) << "CVPixelBuffer format not supported: " << cv_format;
+    return NULL;
+  }
+
+  gfx::Size coded_size(CVImageBufferGetEncodedSize(cv_pixel_buffer));
+  gfx::Rect visible_rect(CVImageBufferGetCleanRect(cv_pixel_buffer));
+  gfx::Size natural_size(CVImageBufferGetDisplaySize(cv_pixel_buffer));
+
+  if (!IsValidConfig(format, coded_size, visible_rect, natural_size))
+    return NULL;
+
+  scoped_refptr<VideoFrame> frame(
+      new VideoFrame(format,
+                     coded_size,
+                     visible_rect,
+                     natural_size,
+                     scoped_ptr<gpu::MailboxHolder>(),
+                     timestamp,
+                     false));
+
+  frame->cv_pixel_buffer_.reset(cv_pixel_buffer, base::scoped_policy::RETAIN);
+  return frame;
+}
+#endif
+
 // static
 scoped_refptr<VideoFrame> VideoFrame::WrapExternalYuvData(
     Format format,
@@ -857,6 +902,12 @@ int VideoFrame::dmabuf_fd(size_t plane) const {
 }
 #endif
 
+#if defined(OS_MACOSX)
+CVPixelBufferRef VideoFrame::cv_pixel_buffer() const {
+  return cv_pixel_buffer_.get();
+}
+#endif
+
 void VideoFrame::HashFrameForTesting(base::MD5Context* context) {
   for (int plane = 0; plane < kMaxPlanes; ++plane) {
     if (!IsValidPlane(plane, format_))