Add support for Tegra V4L2 VDA

content/common/gpu/media/v4l2_video_decode_accelerator.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // This file contains an implementation of VideoDecodeAccelerator
 // that utilizes hardware video decoders, which expose Video4Linux 2 API
 // (http://linuxtv.org/downloads/v4l-dvb-apis/).
 
 #ifndef CONTENT_COMMON_GPU_MEDIA_V4L2_VIDEO_DECODE_ACCELERATOR_H_
 #define CONTENT_COMMON_GPU_MEDIA_V4L2_VIDEO_DECODE_ACCELERATOR_H_
 
 #include <queue>
 #include <vector>
+#include <linux/videodev2.h>

[Pawel Osciak, 2014/03/25 08:21:08]

Why did we not need this before? If this is for v4l2_format, we were already
using it...

[shivdasp, 2014/03/25 10:36:40]

This was for v4l2_format but now if we use frame_buffer_size_ then
current_format_ can go away and hence this too.

On 2014/03/25 08:21:08, Pawel Osciak wrote:

 
 #include "base/callback_forward.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/thread.h"
 #include "content/common/content_export.h"
 #include "content/common/gpu/media/v4l2_video_device.h"
 #include "content/common/gpu/media/video_decode_accelerator_impl.h"
 #include "media/base/limits.h"
@@ skipping 263 matching lines @@
   // caller can error out on resolution change.
   bool DestroyOutputBuffers();
   void ResolutionChangeDestroyBuffers();
 
   // Send decoded pictures to PictureReady.
   void SendPictureReady();
 
   // Callback that indicates a picture has been cleared.
   void PictureCleared();
 
+  // This method determines whether a resolution change event processing
+  // is indeed required by returning true if either:
+  // - width or height of the new format is different than previous format.
+  // - V4L2_CID_MIN_BUFFERS_FOR_CAPTURE has changed.
+  // Returns false otherwise.
+  bool IsResolutionChangeNecessary();
+
   // Our original calling message loop for the child thread.
   scoped_refptr<base::MessageLoopProxy> child_message_loop_proxy_;
 
   // Message loop of the IO thread.
   scoped_refptr<base::MessageLoopProxy> io_message_loop_proxy_;
 
   // WeakPtr<> pointing to |this| for use in posting tasks from the decoder or
   // device worker threads back to the child thread.  Because the worker threads
   // are members of this class, any task running on those threads is guaranteed
   // that this object is still alive.  As a result, tasks posted from the child
@@ skipping 112 matching lines @@
 
   // Make our context current before running any EGL entry points.
   base::Callback<bool(void)> make_context_current_;
 
   // EGL state
   EGLDisplay egl_display_;
 
   // The codec we'll be decoding for.
   media::VideoCodecProfile video_profile_;
 
+  // Stores the current format. This is used to check against
+  // the format received when we dequeue a RESOLUTION_CHANGE event.
+  // Resolution change sequence is only executed if the new format is different
+  // than the current_format_.
+  struct v4l2_format current_format_;
+
   DISALLOW_COPY_AND_ASSIGN(V4L2VideoDecodeAccelerator);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_V4L2_VIDEO_DECODE_ACCELERATOR_H_