[EXPERIMENTAL] Generic stereo codec with index header sending single frames

api/video/video_frame_buffer.cc

 /*
  *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 31 matching lines @@
 }
 
 int I420BufferInterface::ChromaWidth() const {
   return (width() + 1) / 2;
 }
 
 int I420BufferInterface::ChromaHeight() const {
   return (height() + 1) / 2;
 }
 
+bool I420BufferInterface::HasAlpha() const {
+  return DataA() != nullptr && StrideA() != 0;
+}
+
+const uint8_t* I420BufferInterface::DataA() const {
+  return nullptr;
+}
+
+int I420BufferInterface::StrideA() const {
+  return 0;
+}
+
 rtc::scoped_refptr<I420BufferInterface> I420BufferInterface::ToI420() {
   return this;
 }
 
 VideoFrameBuffer::Type I444BufferInterface::type() const {
   return Type::kI444;
 }
 
 int I444BufferInterface::ChromaWidth() const {
   return width();
 }
 
 int I444BufferInterface::ChromaHeight() const {
   return height();
 }
 
 rtc::scoped_refptr<I420BufferInterface> I444BufferInterface::ToI420() {
   rtc::scoped_refptr<I420Buffer> i420_buffer =
       I420Buffer::Create(width(), height());
   libyuv::I444ToI420(DataY(), StrideY(), DataU(), StrideU(), DataV(), StrideV(),
                      i420_buffer->MutableDataY(), i420_buffer->StrideY(),
                      i420_buffer->MutableDataU(), i420_buffer->StrideU(),
                      i420_buffer->MutableDataV(), i420_buffer->StrideV(),
                      width(), height());
   return i420_buffer;
 }
 
 }  // namespace webrtc