Add accelerated video decoder interface, VP8 and H.264 implementations and hook up to V4L2SVDA.

content/common/gpu/media/h264_dpb.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.
 //
 // This file contains an implementation of an H.264 Decoded Picture Buffer
 // used in H264 decoders.
 
 #ifndef CONTENT_COMMON_GPU_MEDIA_H264_DPB_H_
 #define CONTENT_COMMON_GPU_MEDIA_H264_DPB_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
-#include "base/memory/scoped_vector.h"
+#include "base/memory/ref_counted.h"
 #include "media/filters/h264_parser.h"
 
 namespace content {
 
+class V4L2H264Picture;
+
 // A picture (a frame or a field) in the H.264 spec sense.
 // See spec at http://www.itu.int/rec/T-REC-H.264
-struct H264Picture {
+struct H264PictureBase {
   enum Field {
     FIELD_NONE,
     FIELD_TOP,
     FIELD_BOTTOM,
   };
 
+  H264PictureBase();
+
   // Values calculated per H.264 specification or taken from slice header.
   // See spec for more details on each (some names have been converted from
   // CamelCase in spec to Chromium-style names).
   int top_field_order_cnt;
   int bottom_field_order_cnt;
   int pic_order_cnt;
   int pic_order_cnt_msb;
   int pic_order_cnt_lsb;
 
   int pic_num;
@@ skipping 14 matching lines @@
 
   Field field;
 
   // Values from slice_hdr to be used during reference marking and
   // memory management after finishing this picture.
   bool long_term_reference_flag;
   bool adaptive_ref_pic_marking_mode_flag;
   media::H264DecRefPicMarking
       ref_pic_marking[media::H264SliceHeader::kRefListSize];
 
-  typedef std::vector<H264Picture*> PtrVector;
+  // Position in DPB (i.e. index in DPB).
+  int dpb_position;
+};
+
+class H264Picture : public H264PictureBase,
+                    public base::RefCounted<H264Picture> {
+ public:
+  H264Picture() {}

[scherkus (not reviewing), 2015/01/13 01:24:59]

move impl to .cc

see http://dev.chromium.org/developers/coding-style/cpp-dos-and-donts

[Pawel Osciak, 2015/01/13 11:33:34]

Done.

+
+  virtual V4L2H264Picture* AsV4L2H264Picture() { return nullptr; }

[scherkus (not reviewing), 2015/01/13 01:24:59]

is it ever reasonable to construct an H264Picture as opposed to a subclass?

if it isn't, I would make this pure virtual

also .. why not just stick this pure virtual method on H264PictureBase? at least
as far as I can tell I don't see any other subclasses of H264PictureBase

[Pawel Osciak, 2015/01/13 11:33:34]

Yes, if we intend to use H264Decoder without hiding any implementation details
in H264Picture.
The only reason for the ugly existence of H264PictureBase was that I wanted to
have a memset(this,0,...) constructor for it. I'm not aware of any other method
to do this...

[scherkus (not reviewing), 2015/01/14 18:44:13]

That's a poor reason if you ask me :)

You're justifying H264PictureBase and increased complexity throughout the
codebase so you can save a few lines of code inside of the H264PictureBase
constructor by calling memset(this, ...).

This is C++ code. Please set all fields to 0/false in the initializer list and
clean up the class hierarchy.

+
+  using Vector = std::vector<scoped_refptr<H264Picture>>;
+
+ protected:
+  friend class base::RefCounted<H264Picture>;
+  virtual ~H264Picture() {}

[scherkus (not reviewing), 2015/01/13 01:24:59]

override

[Pawel Osciak, 2015/01/13 11:33:34]

Done.

+
+  DISALLOW_COPY_AND_ASSIGN(H264Picture);
 };
 
 // DPB - Decoded Picture Buffer.
 // Stores decoded pictures that will be used for future display
 // and/or reference.
 class H264DPB {
  public:
   H264DPB();
   ~H264DPB();
 
   void set_max_num_pics(size_t max_num_pics);
-  size_t max_num_pics() { return max_num_pics_; }
+  size_t max_num_pics() const { return max_num_pics_; }
 
   // Remove unused (not reference and already outputted) pictures from DPB
   // and free it.
   void DeleteUnused();
 
   // Remove a picture by its pic_order_cnt and free it.
   void DeleteByPOC(int poc);
 
   // Clear DPB.
   void Clear();
 
   // Store picture in DPB. DPB takes ownership of its resources.
-  void StorePic(H264Picture* pic);
+  void StorePic(const scoped_refptr<H264Picture>& pic);
 
   // Return the number of reference pictures in DPB.
   int CountRefPics();
 
   // Mark all pictures in DPB as unused for reference.
   void MarkAllUnusedForRef();
 
   // Return a short-term reference picture by its pic_num.
-  H264Picture* GetShortRefPicByPicNum(int pic_num);
+  scoped_refptr<H264Picture> GetShortRefPicByPicNum(int pic_num);
 
   // Return a long-term reference picture by its long_term_pic_num.
-  H264Picture* GetLongRefPicByLongTermPicNum(int pic_num);
+  scoped_refptr<H264Picture> GetLongRefPicByLongTermPicNum(int pic_num);
 
   // Return the short reference picture with lowest frame_num. Used for sliding
   // window memory management.
-  H264Picture* GetLowestFrameNumWrapShortRefPic();
+  scoped_refptr<H264Picture> GetLowestFrameNumWrapShortRefPic();
 
   // Append all pictures that have not been outputted yet to the passed |out|
   // vector, sorted by lowest pic_order_cnt (in output order).
-  void GetNotOutputtedPicsAppending(H264Picture::PtrVector& out);
+  void GetNotOutputtedPicsAppending(H264Picture::Vector* out);
 
   // Append all short term reference pictures to the passed |out| vector.
-  void GetShortTermRefPicsAppending(H264Picture::PtrVector& out);
+  void GetShortTermRefPicsAppending(H264Picture::Vector* out);
 
   // Append all long term reference pictures to the passed |out| vector.
-  void GetLongTermRefPicsAppending(H264Picture::PtrVector& out);
+  void GetLongTermRefPicsAppending(H264Picture::Vector* out);
 
   // Iterators for direct access to DPB contents.
   // Will be invalidated after any of Remove* calls.
-  typedef ScopedVector<H264Picture> Pictures;
-  Pictures::iterator begin() { return pics_.begin(); }
-  Pictures::iterator end() { return pics_.end(); }
-  Pictures::reverse_iterator rbegin() { return pics_.rbegin(); }
-  Pictures::reverse_iterator rend() { return pics_.rend(); }
+  H264Picture::Vector::iterator begin() { return pics_.begin(); }
+  H264Picture::Vector::iterator end() { return pics_.end(); }
+  H264Picture::Vector::const_iterator begin() const { return pics_.begin(); }
+  H264Picture::Vector::const_iterator end() const { return pics_.end(); }
+  H264Picture::Vector::reverse_iterator rbegin() { return pics_.rbegin(); }
+  H264Picture::Vector::reverse_iterator rend() { return pics_.rend(); }
 
   size_t size() const { return pics_.size(); }
   bool IsFull() const { return pics_.size() == max_num_pics_; }
 
   // Per H264 spec, increase to 32 if interlaced video is supported.
   enum { kDPBMaxSize = 16, };
 
  private:
-  Pictures pics_;
+  void UpdatePicPositions();
+
+  H264Picture::Vector pics_;
   size_t max_num_pics_;
 
   DISALLOW_COPY_AND_ASSIGN(H264DPB);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_H264_DPB_H_