modules/video_coding refactorings

webrtc/modules/video_coding/main/source/session_info.h

-/*
- *  Copyright (c) 2011 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_MAIN_SOURCE_SESSION_INFO_H_
-#define WEBRTC_MODULES_VIDEO_CODING_MAIN_SOURCE_SESSION_INFO_H_
-
-#include <list>
-
-#include "webrtc/modules/include/module_common_types.h"
-#include "webrtc/modules/video_coding/main/interface/video_coding.h"
-#include "webrtc/modules/video_coding/main/source/packet.h"
-#include "webrtc/typedefs.h"
-
-namespace webrtc {
-// Used to pass data from jitter buffer to session info.
-// This data is then used in determining whether a frame is decodable.
-struct FrameData {
-  int64_t rtt_ms;
-  float rolling_average_packets_per_frame;
-};
-
-class VCMSessionInfo {
- public:
-  VCMSessionInfo();
-
-  void UpdateDataPointers(const uint8_t* old_base_ptr,
-                          const uint8_t* new_base_ptr);
-  // NACK - Building the NACK lists.
-  // Build hard NACK list: Zero out all entries in list up to and including
-  // _lowSeqNum.
-  int BuildHardNackList(int* seq_num_list,
-                        int seq_num_list_length,
-                        int nack_seq_nums_index);
-
-  // Build soft NACK list:  Zero out only a subset of the packets, discard
-  // empty packets.
-  int BuildSoftNackList(int* seq_num_list,
-                        int seq_num_list_length,
-                        int nack_seq_nums_index,
-                        int rtt_ms);
-  void Reset();
-  int InsertPacket(const VCMPacket& packet,
-                   uint8_t* frame_buffer,
-                   VCMDecodeErrorMode enable_decodable_state,
-                   const FrameData& frame_data);
-  bool complete() const;
-  bool decodable() const;
-
-  // Builds fragmentation headers for VP8, each fragment being a decodable
-  // VP8 partition. Returns the total number of bytes which are decodable. Is
-  // used instead of MakeDecodable for VP8.
-  size_t BuildVP8FragmentationHeader(uint8_t* frame_buffer,
-                                     size_t frame_buffer_length,
-                                     RTPFragmentationHeader* fragmentation);
-
-  // Makes the frame decodable. I.e., only contain decodable NALUs. All
-  // non-decodable NALUs will be deleted and packets will be moved to in
-  // memory to remove any empty space.
-  // Returns the number of bytes deleted from the session.
-  size_t MakeDecodable();
-
-  // Sets decodable_ to false.
-  // Used by the dual decoder. After the mode is changed to kNoErrors from
-  // kWithErrors or kSelective errors, any states that have been marked
-  // decodable and are not complete are marked as non-decodable.
-  void SetNotDecodableIfIncomplete();
-
-  size_t SessionLength() const;
-  int NumPackets() const;
-  bool HaveFirstPacket() const;
-  bool HaveLastPacket() const;
-  bool session_nack() const;
-  webrtc::FrameType FrameType() const { return frame_type_; }
-  int LowSequenceNumber() const;
-
-  // Returns highest sequence number, media or empty.
-  int HighSequenceNumber() const;
-  int PictureId() const;
-  int TemporalId() const;
-  bool LayerSync() const;
-  int Tl0PicId() const;
-  bool NonReference() const;
-
-  void SetGofInfo(const GofInfoVP9& gof_info, size_t idx);
-
-  // The number of packets discarded because the decoder can't make use of
-  // them.
-  int packets_not_decodable() const;
-
- private:
-  enum { kMaxVP8Partitions = 9 };
-
-  typedef std::list<VCMPacket> PacketList;
-  typedef PacketList::iterator PacketIterator;
-  typedef PacketList::const_iterator PacketIteratorConst;
-  typedef PacketList::reverse_iterator ReversePacketIterator;
-
-  void InformOfEmptyPacket(uint16_t seq_num);
-
-  // Finds the packet of the beginning of the next VP8 partition. If
-  // none is found the returned iterator points to |packets_.end()|.
-  // |it| is expected to point to the last packet of the previous partition,
-  // or to the first packet of the frame. |packets_skipped| is incremented
-  // for each packet found which doesn't have the beginning bit set.
-  PacketIterator FindNextPartitionBeginning(PacketIterator it) const;
-
-  // Returns an iterator pointing to the last packet of the partition pointed to
-  // by |it|.
-  PacketIterator FindPartitionEnd(PacketIterator it) const;
-  static bool InSequence(const PacketIterator& it,
-                         const PacketIterator& prev_it);
-  size_t InsertBuffer(uint8_t* frame_buffer,
-                      PacketIterator packetIterator);
-  size_t Insert(const uint8_t* buffer,
-                size_t length,
-                bool insert_start_code,
-                uint8_t* frame_buffer);
-  void ShiftSubsequentPackets(PacketIterator it, int steps_to_shift);
-  PacketIterator FindNaluEnd(PacketIterator packet_iter) const;
-  // Deletes the data of all packets between |start| and |end|, inclusively.
-  // Note that this function doesn't delete the actual packets.
-  size_t DeletePacketData(PacketIterator start,
-                          PacketIterator end);
-  void UpdateCompleteSession();
-
-  // When enabled, determine if session is decodable, i.e. incomplete but
-  // would be sent to the decoder.
-  // Note: definition assumes random loss.
-  // A frame is defined to be decodable when:
-  //  Round trip time is higher than threshold
-  //  It is not a key frame
-  //  It has the first packet: In VP8 the first packet contains all or part of
-  //    the first partition, which consists of the most relevant information for
-  //    decoding.
-  //  Either more than the upper threshold of the average number of packets per
-  //        frame is present
-  //      or less than the lower threshold of the average number of packets per
-  //        frame is present: suggests a small frame. Such a frame is unlikely
-  //        to contain many motion vectors, so having the first packet will
-  //        likely suffice. Once we have more than the lower threshold of the
-  //        frame, we know that the frame is medium or large-sized.
-  void UpdateDecodableSession(const FrameData& frame_data);
-
-  // If this session has been NACKed by the jitter buffer.
-  bool session_nack_;
-  bool complete_;
-  bool decodable_;
-  webrtc::FrameType frame_type_;
-  // Packets in this frame.
-  PacketList packets_;
-  int empty_seq_num_low_;
-  int empty_seq_num_high_;
-
-  // The following two variables correspond to the first and last media packets
-  // in a session defined by the first packet flag and the marker bit.
-  // They are not necessarily equal to the front and back packets, as packets
-  // may enter out of order.
-  // TODO(mikhal): Refactor the list to use a map.
-  int first_packet_seq_num_;
-  int last_packet_seq_num_;
-};
-
-}  // namespace webrtc
-
-#endif  // WEBRTC_MODULES_VIDEO_CODING_MAIN_SOURCE_SESSION_INFO_H_