tor-browser

The Tor Browser
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decoding_state.h (3163B)


      1 /*
      2 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
      3 *
      4 *  Use of this source code is governed by a BSD-style license
      5 *  that can be found in the LICENSE file in the root of the source
      6 *  tree. An additional intellectual property rights grant can be found
      7 *  in the file PATENTS.  All contributing project authors may
      8 *  be found in the AUTHORS file in the root of the source tree.
      9 */
     10 
     11 #ifndef MODULES_VIDEO_CODING_DEPRECATED_DECODING_STATE_H_
     12 #define MODULES_VIDEO_CODING_DEPRECATED_DECODING_STATE_H_
     13 
     14 #include <cstdint>
     15 #include <map>
     16 #include <set>
     17 #include <vector>
     18 
     19 namespace webrtc {
     20 
     21 // Forward declarations
     22 struct NaluInfo;
     23 class VCMFrameBuffer;
     24 class VCMPacket;
     25 
     26 class VCMDecodingState {
     27 public:
     28  // The max number of bits used to reference back
     29  // to a previous frame when using flexible mode.
     30  static const uint16_t kNumRefBits = 7;
     31  static const uint16_t kFrameDecodedLength = 1 << kNumRefBits;
     32 
     33  VCMDecodingState();
     34  ~VCMDecodingState();
     35  // Check for old frame
     36  bool IsOldFrame(const VCMFrameBuffer* frame) const;
     37  // Check for old packet
     38  bool IsOldPacket(const VCMPacket* packet) const;
     39  // Check for frame continuity based on current decoded state. Use best method
     40  // possible, i.e. temporal info, picture ID or sequence number.
     41  bool ContinuousFrame(const VCMFrameBuffer* frame) const;
     42  void SetState(const VCMFrameBuffer* frame);
     43  void CopyFrom(const VCMDecodingState& state);
     44  bool UpdateEmptyFrame(const VCMFrameBuffer* frame);
     45  // Update the sequence number if the timestamp matches current state and the
     46  // sequence number is higher than the current one. This accounts for packets
     47  // arriving late.
     48  void UpdateOldPacket(const VCMPacket* packet);
     49  void SetSeqNum(uint16_t new_seq_num);
     50  void Reset();
     51  uint32_t time_stamp() const;
     52  uint16_t sequence_num() const;
     53  // Return true if at initial state.
     54  bool in_initial_state() const;
     55  // Return true when sync is on - decode all layers.
     56  bool full_sync() const;
     57 
     58 private:
     59  void UpdateSyncState(const VCMFrameBuffer* frame);
     60  // Designated continuity functions
     61  bool ContinuousPictureId(int picture_id) const;
     62  bool ContinuousSeqNum(uint16_t seq_num) const;
     63  bool ContinuousLayer(int temporal_id, int tl0_pic_id) const;
     64  bool ContinuousFrameRefs(const VCMFrameBuffer* frame) const;
     65  bool UsingPictureId(const VCMFrameBuffer* frame) const;
     66  bool UsingFlexibleMode(const VCMFrameBuffer* frame) const;
     67  bool AheadOfFramesDecodedClearedTo(uint16_t index) const;
     68  bool HaveSpsAndPps(const std::vector<NaluInfo>& nalus) const;
     69 
     70  // Keep state of last decoded frame.
     71  // TODO(mikhal/stefan): create designated classes to handle these types.
     72  uint16_t sequence_num_;
     73  uint32_t time_stamp_;
     74  int picture_id_;
     75  int temporal_id_;
     76  int tl0_pic_id_;
     77  bool full_sync_;  // Sync flag when temporal layers are used.
     78  bool in_initial_state_;
     79 
     80  // Used to check references in flexible mode.
     81  bool frame_decoded_[kFrameDecodedLength];
     82  uint16_t frame_decoded_cleared_to_;
     83  std::set<int> received_sps_;
     84  std::map<int, int> received_pps_;
     85 };
     86 
     87 }  // namespace webrtc
     88 
     89 #endif  // MODULES_VIDEO_CODING_DEPRECATED_DECODING_STATE_H_