media: Add support for playback of VP8 Alpha video streams

media/base/decoder_buffer.cc

Index: media/base/decoder_buffer.cc
diff --git a/media/base/decoder_buffer.cc b/media/base/decoder_buffer.cc
index 03f9bbbc566abc70abb878bc0dc00b34c82b7093..aec45211f10d3d68998e304b445e463ea55b0f61 100644
--- a/media/base/decoder_buffer.cc
+++ b/media/base/decoder_buffer.cc
@@ -10,12 +10,14 @@
 namespace media {
 
 DecoderBuffer::DecoderBuffer(int size)
-    : size_(size) {
+    : size_(size),
+      side_data_size_(0) {
   Initialize();
 }
 
 DecoderBuffer::DecoderBuffer(const uint8* data, int size)
-    : size_(size) {
+    : size_(size),
+      side_data_size_(0) {
   if (!data) {
     CHECK_EQ(size_, 0);
     return;
@@ -25,6 +27,20 @@ DecoderBuffer::DecoderBuffer(const uint8* data, int size)
   memcpy(data_.get(), data, size_);
 }
 
+DecoderBuffer::DecoderBuffer(const uint8* data, int size,
+                             const uint8* side_data, int side_data_size)
+    : size_(size),
+      side_data_size_(side_data_size) {
+  if (!data) {
+    CHECK_EQ(size_, 0);
+    return;
+  }
+
+  Initialize();
+  memcpy(data_.get(), data, size_);
+  memcpy(side_data_.get(), side_data, side_data_size_);
+}
+
 DecoderBuffer::~DecoderBuffer() {}
 
 void DecoderBuffer::Initialize() {
@@ -32,6 +48,11 @@ void DecoderBuffer::Initialize() {
   data_.reset(reinterpret_cast<uint8*>(
       base::AlignedAlloc(size_ + kPaddingSize, kAlignmentSize)));
   memset(data_.get() + size_, 0, kPaddingSize);
+  if (side_data_size_ > 0) {
+    side_data_.reset(reinterpret_cast<uint8*>(
+        base::AlignedAlloc(side_data_size_ + kPaddingSize, kAlignmentSize)));
+    memset(side_data_.get() + side_data_size_, 0, kPaddingSize);
+  }
 }
 
 // static
@@ -43,6 +64,18 @@ scoped_refptr<DecoderBuffer> DecoderBuffer::CopyFrom(const uint8* data,
 }
 
 // static
+scoped_refptr<DecoderBuffer> DecoderBuffer::CopyFrom(const uint8* data,
+                                                     int data_size,
+                                                     const uint8* side_data,
+                                                     int side_data_size) {
+  // If you hit this CHECK you likely have a bug in a demuxer. Go fix it.
+  CHECK(data);
+  CHECK(side_data);
+  return make_scoped_refptr(new DecoderBuffer(data, data_size,
+                                              side_data, side_data_size));
+}
+
+// static
 scoped_refptr<DecoderBuffer> DecoderBuffer::CreateEOSBuffer() {
   return make_scoped_refptr(new DecoderBuffer(NULL, 0));
 }
@@ -82,6 +115,16 @@ int DecoderBuffer::GetDataSize() const {
   return size_;
 }
 
+const uint8* DecoderBuffer::GetSideData() const {
+  DCHECK(!IsEndOfStream());
+  return side_data_.get();
+}
+
+int DecoderBuffer::GetSideDataSize() const {
+  DCHECK(!IsEndOfStream());
+  return side_data_size_;
+}
+
 const DecryptConfig* DecoderBuffer::GetDecryptConfig() const {
   DCHECK(!IsEndOfStream());
   return decrypt_config_.get();
@@ -105,6 +148,7 @@ std::string DecoderBuffer::AsHumanReadableString() {
   s << "timestamp: " << timestamp_.InMicroseconds()
     << " duration: " << duration_.InMicroseconds()
     << " size: " << size_
+    << " side_data_size: " << side_data_size_
     << " encrypted: " << (decrypt_config_ != NULL);
   return s.str();
 }