Support configuration changes in VTVideoDecodeAccelerator.

content/common/gpu/media/vt_video_decode_accelerator.h

Index: content/common/gpu/media/vt_video_decode_accelerator.h
diff --git a/content/common/gpu/media/vt_video_decode_accelerator.h b/content/common/gpu/media/vt_video_decode_accelerator.h
index cd56db2cc81d861e8e7cdb630df5b6719a4ffe10..03d59570d38e482d3b0d1e737960d61db68c4247 100644
--- a/content/common/gpu/media/vt_video_decode_accelerator.h
+++ b/content/common/gpu/media/vt_video_decode_accelerator.h
@@ -94,13 +94,24 @@ class VTVideoDecodeAccelerator
 
   // Methods for interacting with |client_|. Run on |gpu_task_runner_|.
   void OutputTask(DecodedFrame frame);
-  void SizeChangedTask(gfx::Size coded_size);
   void NotifyError(Error error);
 
   // Send decoded frames up to and including |up_to_bitstream_id|, and return
   // the last sent |bitstream_id|.
   int32_t SendPictures(int32_t up_to_bitstream_id);
 
+  // Internal helper for SendPictures(): Drop frames with no image data up to
+  // the next action, so that if there is still a frame in the queue it is
+  // guaranteed to have image data, and thus it is time to set up the GPU
+  // context.

[Pawel Osciak, 2014/11/02 23:09:52]

Parameters and return value are unclear.

[sandersd (OOO until July 31), 2014/11/03 21:14:25]

Done.

+  int32_t ProcessDroppedFrames(
+      int32_t last_sent_bitstream_id,
+      int32_t up_to_bitstream_id);
+
+  // Internal helper for SendPictures(): Check if the next frame has a size
+  // different from the current picture buffers, and request new ones if so.
+  void ProcessSizeChange();
+
   // Since VideoToolbox has no reset feature (only flush), and the VDA API
   // allows Decode() and Flush() calls during a reset operation, it's possible
   // to have multiple pending actions at once. We handle the fully general case
@@ -127,17 +138,32 @@ class VTVideoDecodeAccelerator
   CGLContextObj cgl_context_;
   base::Callback<bool(void)> make_context_current_;
   media::VideoDecodeAccelerator::Client* client_;
-  bool has_error_;  // client_->NotifyError() called.
-  gfx::Size texture_size_;
+
+  // client_->NotifyError() called.
+  bool has_error_;
+
+  // Size of assigned picture buffers.
+  gfx::Size picture_size_;
+
+  // Queue of actions so that we can quickly discover what the next action will
+  // be; this is useful because we are dropping all frames when the next action
+  // is ACTION_RESET or ACTION_DESTROY.
   std::queue<PendingAction> pending_actions_;
+
+  // Queue of bitstreams currently being decoded. This is mostly needed to be

[Pawel Osciak, 2014/11/02 23:09:52]

Or waiting to be decoded...

[sandersd (OOO until July 31), 2014/11/03 21:14:25]

Done.

+  // sure we free them all in Destroy().
   std::queue<int32_t> pending_bitstream_ids_;
 
-  // Texture IDs of pictures.
-  // TODO(sandersd): A single map of structs holding picture data.
+  // All picture buffers assigned to us. Used to check if reused picture buffers
+  // should be added back to the available list or released. (They are not
+  // released immediately because we need the reuse event to free the binding.)
+  std::set<int32_t> assigned_picture_ids_;
+
+  // Texture IDs of assigned pictures.
   std::map<int32_t, uint32_t> texture_ids_;
 
   // Pictures ready to be rendered to.
-  std::queue<int32_t> available_picture_ids_;
+  std::vector<int32_t> available_picture_ids_;
 
   // Decoded frames ready to render.
   std::queue<DecodedFrame> decoded_frames_;
@@ -152,7 +178,10 @@ class VTVideoDecodeAccelerator
   base::ScopedCFTypeRef<CMFormatDescriptionRef> format_;
   base::ScopedCFTypeRef<VTDecompressionSessionRef> session_;
   media::H264Parser parser_;
-  gfx::Size coded_size_;
+
+  std::vector<uint8_t> last_sps_;
+  std::vector<uint8_t> last_spsext_;
+  std::vector<uint8_t> last_pps_;
 
   //
   // Shared state (set up and torn down on GPU thread).