RtpFrameObject::GetCodecHeader now return rtc::Optional<RTPVideoTypeHeader>

webrtc/modules/video_coding/frame_object.h

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #ifndef WEBRTC_MODULES_VIDEO_CODING_FRAME_OBJECT_H_
 #define WEBRTC_MODULES_VIDEO_CODING_FRAME_OBJECT_H_
 
+#include "webrtc/base/optional.h"
 #include "webrtc/common_types.h"
 #include "webrtc/modules/include/module_common_types.h"
 #include "webrtc/modules/video_coding/encoded_frame.h"
 
 namespace webrtc {
 namespace video_coding {
 
 class FrameObject : public webrtc::VCMEncodedFrame {
  public:
   static const uint8_t kMaxFrameReferences = 5;
@@ skipping 40 matching lines @@
   ~RtpFrameObject();
   uint16_t first_seq_num() const;
   uint16_t last_seq_num() const;
   int times_nacked() const;
   enum FrameType frame_type() const;
   VideoCodecType codec_type() const;
   bool GetBitstream(uint8_t* destination) const override;
   uint32_t Timestamp() const override;
   int64_t ReceivedTime() const override;
   int64_t RenderTime() const override;
-  RTPVideoTypeHeader* GetCodecHeader() const;
+  rtc::Optional<RTPVideoTypeHeader> GetCodecHeader() const;

[terelius, 2016/11/02 13:08:18]

How large is the RTPVideoTypeHeader, and how often is the function called?
(I.e., will this have any performance impact?)

[philipel, 2016/11/02 13:12:24]

It is 1624 bytes, and it is called ~1 time per frame (can be more if the frame
is retried in the RtpFrameReferenceFinder)

[terelius, 2016/11/02 13:18:38]

A 1.5 kB header seems like a lot. Does it have to be that large? Do you need the
entire header, or would it be possible to just copy parts of it as a future
optimization?

[philipel, 2016/11/02 13:26:14]

It is quite large (in fact it is larger than the bitstream data that we want to
avoid copying) due to the GofInfoVP9 which contains multiple arrays and a matrix
that is mostly unused. Maybe the Gof can be stored more efficiently.

[terelius, 2016/11/02 13:34:49]

Ok. Can you file a feature request in the bugtracker for a more compact
representation of the Gof? A sparse representation of the matrix might be
useful.

 
  private:
   rtc::scoped_refptr<PacketBuffer> packet_buffer_;
   enum FrameType frame_type_;
   VideoCodecType codec_type_;
   uint16_t first_seq_num_;
   uint16_t last_seq_num_;
   uint32_t timestamp_;
   int64_t received_time_;
 
   // Equal to times nacked of the packet with the highet times nacked
   // belonging to this frame.
   int times_nacked_;
 };
 
 }  // namespace video_coding
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_VIDEO_CODING_FRAME_OBJECT_H_