Send hardware video frames with mailboxes.

media/base/video_frame.h

 // Copyright (c) 2012 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.
 
 #ifndef MEDIA_BASE_VIDEO_FRAME_H_
 #define MEDIA_BASE_VIDEO_FRAME_H_
 
 #include "base/callback.h"
 #include "base/md5.h"
+#include "gpu/command_buffer/common/mailbox.h"
 #include "media/base/buffers.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/size.h"
 
 class SkBitmap;
 
 namespace media {
 
 class MEDIA_EXPORT VideoFrame : public base::RefCountedThreadSafe<VideoFrame> {
  public:
@@ skipping 24 matching lines @@
     YV16 = 7,  // 16bpp YVU planar 1x1 Y, 2x1 VU samples
     EMPTY = 9,  // An empty frame.
     I420 = 11,  // 12bpp YVU planar 1x1 Y, 2x2 UV samples.
     NATIVE_TEXTURE = 12,  // Native texture.  Pixel-format agnostic.
 #if defined(GOOGLE_TV)
     HOLE = 13,  // Hole frame.
 #endif
     YV12A = 14,  // 20bpp YUVA planar 1x1 Y, 2x2 VU, 1x1 A samples.
   };
 
+  // This class calls the TextureNoLongerNeededCallback when the last reference
+  // on the class is destroyed. The VideoFrame holds a reference to the mailbox
+  // but anyone else who queries the mailbox should also hold a reference while
+  // it is uses the mailbox, to ensure it remains valid. When finished with the
+  // mailbox, call Return() with a new sync point, to ensure the mailbox remains
+  // valid for the issued commands.
+  class MEDIA_EXPORT MailboxHolder
+      : public base::RefCountedThreadSafe<MailboxHolder> {
+   public:
+    typedef base::Callback<void(uint32 sync_point)>
+        TextureNoLongerNeededCallback;
+
+    MailboxHolder(const gpu::Mailbox& mailbox,
+                  unsigned sync_point,
+                  const TextureNoLongerNeededCallback& release_callback);
+
+    const gpu::Mailbox& mailbox() const { return mailbox_; }
+    unsigned sync_point() const { return sync_point_; }
+
+    void Return(unsigned sync_point) { sync_point_ = sync_point; }
+
+   private:
+    friend class base::RefCountedThreadSafe<MailboxHolder>;
+    ~MailboxHolder();
+
+    gpu::Mailbox mailbox_;
+    unsigned sync_point_;
+    TextureNoLongerNeededCallback release_callback_;
+  };
+
+
   // Creates a new frame in system memory with given parameters. Buffers for
   // the frame are allocated but not initialized.
   // |coded_size| is the width and height of the frame data in pixels.
   // |visible_rect| is the visible portion of |coded_size|, after cropping (if
   // any) is applied.
   // |natural_size| is the width and height of the frame when the frame's aspect
   // ratio is applied to |visible_rect|.
   static scoped_refptr<VideoFrame> CreateFrame(
       Format format,
       const gfx::Size& coded_size,
@@ skipping 16 matching lines @@
   // frame is destroyed |no_longer_needed_cb.Run()| will be called.
   // |coded_size| is the width and height of the frame data in pixels.
   // |visible_rect| is the visible portion of |coded_size|, after cropping (if
   // any) is applied.
   // |natural_size| is the width and height of the frame when the frame's aspect
   // ratio is applied to |visible_rect|.
 
   // |read_pixels_cb| may be used to do (slow!) readbacks from the
   // texture to main memory.
   static scoped_refptr<VideoFrame> WrapNativeTexture(
-      uint32 texture_id,
+      const scoped_refptr<MailboxHolder>& mailbox_holder,
       uint32 texture_target,
       const gfx::Size& coded_size,
       const gfx::Rect& visible_rect,
       const gfx::Size& natural_size,
       base::TimeDelta timestamp,
       const ReadPixelsCB& read_pixels_cb,
       const base::Closure& no_longer_needed_cb);
 
   // Read pixels from the native texture backing |*this| and write
   // them to |pixels| as BGRA.  |pixels| must point to a buffer at
@@ skipping 50 matching lines @@
   //
   // As opposed to stride(), row_bytes() refers to the bytes representing
   // frame data scanlines (coded_size.width() pixels, without stride padding).
   int row_bytes(size_t plane) const;
   int rows(size_t plane) const;
 
   // Returns pointer to the buffer for a given plane. The memory is owned by
   // VideoFrame object and must not be freed by the caller.
   uint8* data(size_t plane) const;
 
-  // Returns the ID of the native texture wrapped by this frame.  Only valid to
-  // call if this is a NATIVE_TEXTURE frame.
-  uint32 texture_id() const;
+  // Returns the mailbox of the native texture wrapped by this frame. Only
+  // valid to call if this is a NATIVE_TEXTURE frame. Before using the
+  // mailbox, the caller must wait for the included sync point.
+  const scoped_refptr<MailboxHolder>& texture_mailbox() const;
 
   // Returns the texture target. Only valid for NATIVE_TEXTURE frames.
   uint32 texture_target() const;
 
   // Returns true if this VideoFrame represents the end of the stream.
   bool IsEndOfStream() const;
 
   base::TimeDelta GetTimestamp() const {
     return timestamp_;
   }
@@ skipping 36 matching lines @@
   gfx::Size natural_size_;
 
   // Array of strides for each plane, typically greater or equal to the width
   // of the surface divided by the horizontal sampling period.  Note that
   // strides can be negative.
   int32 strides_[kMaxPlanes];
 
   // Array of data pointers to each plane.
   uint8* data_[kMaxPlanes];
 
-  // Native texture ID, if this is a NATIVE_TEXTURE frame.
-  uint32 texture_id_;
+  // Native texture mailbox, if this is a NATIVE_TEXTURE frame.
+  scoped_refptr<MailboxHolder> texture_mailbox_holder_;
   uint32 texture_target_;
   ReadPixelsCB read_pixels_cb_;
 
   base::Closure no_longer_needed_cb_;
 
   base::TimeDelta timestamp_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoFrame);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_VIDEO_FRAME_H_