Add a GpuMemoryBuffer pool that creates hardware backed VideoFrames.

media/video/gpu_memory_buffer_video_frame_pool.h

+// Copyright (c) 2015 The Chromium Authors. All rights reserved.

[reveman, 2015/05/15 05:44:03]

nit: no "(c)" in new files

[Daniele Castagna, 2015/05/15 05:52:25]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_VIDEO_GPU_MEMORY_BUFFER_VIDEO_FRAME_POOL_H_
+#define MEDIA_VIDEO_GPU_MEMORY_BUFFER_VIDEO_FRAME_POOL_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "media/base/video_frame.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+}
+
+namespace media {
+class GpuVideoAcceleratorFactories;
+
+// Interface to a pool of GpuMemoryBuffers/textues/images that can be used to
+// transform software VideoFrames to VideoFrames backed by native textures.
+// The resources used by the VideoFrame created by the pool will be
+// automatically put back into the pool once the frame is destroyed.
+// The pool recycles resources to a void unnecessarily allocating and
+// destroying textures, images and GpuMemoryBuffer that could result
+// in a round trip to the browser/GPU process.
+class MEDIA_EXPORT GpuMemoryBufferVideoFramePool {
+ public:
+  GpuMemoryBufferVideoFramePool(
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+      const scoped_refptr<GpuVideoAcceleratorFactories>& gpu_factories);
+  ~GpuMemoryBufferVideoFramePool();
+
+  // Returns a new VideoFrame containing only mailboxes to native resources.
+  // The content of the returned object is copied from the software-allocated
+  // |video_frame|.
+  // If it's not possible to create a new hardware VideoFrame, |video_frame|
+  // itself will be returned.
+  scoped_refptr<VideoFrame> MaybeCreateHardwareFrame(
+      const scoped_refptr<VideoFrame>& video_frame);
+
+ private:
+  class PoolImpl;
+  scoped_refptr<PoolImpl> pool_impl_;
+
+  DISALLOW_COPY_AND_ASSIGN(GpuMemoryBufferVideoFramePool);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_VIDEO_GPU_MEMORY_BUFFER_VIDEO_FRAME_POOL_H_