1 /* 2 * Copyright (c) 2013 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 WEBRTC_MODULES_AUDIO_CODING_NETEQ_DECISION_LOGIC_H_ 12 #define WEBRTC_MODULES_AUDIO_CODING_NETEQ_DECISION_LOGIC_H_ 13 14 #include "webrtc/base/constructormagic.h" 15 #include "webrtc/modules/audio_coding/neteq/defines.h" 16 #include "webrtc/modules/audio_coding/neteq/include/neteq.h" 17 #include "webrtc/typedefs.h" 18 19 namespace webrtc { 20 21 // Forward declarations. 22 class BufferLevelFilter; 23 class DecoderDatabase; 24 class DelayManager; 25 class Expand; 26 class PacketBuffer; 27 class SyncBuffer; 28 struct RTPHeader; 29 30 // This is the base class for the decision tree implementations. Derived classes 31 // must implement the method GetDecisionSpecialized(). 32 class DecisionLogic { 33 public: 34 // Static factory function which creates different types of objects depending 35 // on the |playout_mode|. 36 static DecisionLogic* Create(int fs_hz, 37 size_t output_size_samples, 38 NetEqPlayoutMode playout_mode, 39 DecoderDatabase* decoder_database, 40 const PacketBuffer& packet_buffer, 41 DelayManager* delay_manager, 42 BufferLevelFilter* buffer_level_filter); 43 44 // Constructor. 45 DecisionLogic(int fs_hz, 46 size_t output_size_samples, 47 NetEqPlayoutMode playout_mode, 48 DecoderDatabase* decoder_database, 49 const PacketBuffer& packet_buffer, 50 DelayManager* delay_manager, 51 BufferLevelFilter* buffer_level_filter); 52 53 // Destructor. ~DecisionLogic()54 virtual ~DecisionLogic() {} 55 56 // Resets object to a clean state. 57 void Reset(); 58 59 // Resets parts of the state. Typically done when switching codecs. 60 void SoftReset(); 61 62 // Sets the sample rate and the output block size. 63 void SetSampleRate(int fs_hz, size_t output_size_samples); 64 65 // Returns the operation that should be done next. |sync_buffer| and |expand| 66 // are provided for reference. |decoder_frame_length| is the number of samples 67 // obtained from the last decoded frame. If there is a packet available, the 68 // packet header should be supplied in |packet_header|; otherwise it should 69 // be NULL. The mode resulting form the last call to NetEqImpl::GetAudio is 70 // supplied in |prev_mode|. If there is a DTMF event to play, |play_dtmf| 71 // should be set to true. The output variable |reset_decoder| will be set to 72 // true if a reset is required; otherwise it is left unchanged (i.e., it can 73 // remain true if it was true before the call). 74 // This method end with calling GetDecisionSpecialized to get the actual 75 // return value. 76 Operations GetDecision(const SyncBuffer& sync_buffer, 77 const Expand& expand, 78 size_t decoder_frame_length, 79 const RTPHeader* packet_header, 80 Modes prev_mode, 81 bool play_dtmf, 82 bool* reset_decoder); 83 84 // These methods test the |cng_state_| for different conditions. CngRfc3389On()85 bool CngRfc3389On() const { return cng_state_ == kCngRfc3389On; } CngOff()86 bool CngOff() const { return cng_state_ == kCngOff; } 87 88 // Resets the |cng_state_| to kCngOff. SetCngOff()89 void SetCngOff() { cng_state_ = kCngOff; } 90 91 // Reports back to DecisionLogic whether the decision to do expand remains or 92 // not. Note that this is necessary, since an expand decision can be changed 93 // to kNormal in NetEqImpl::GetDecision if there is still enough data in the 94 // sync buffer. 95 virtual void ExpandDecision(Operations operation); 96 97 // Adds |value| to |sample_memory_|. AddSampleMemory(int32_t value)98 void AddSampleMemory(int32_t value) { 99 sample_memory_ += value; 100 } 101 102 // Accessors and mutators. set_sample_memory(int32_t value)103 void set_sample_memory(int32_t value) { sample_memory_ = value; } generated_noise_samples()104 size_t generated_noise_samples() const { return generated_noise_samples_; } set_generated_noise_samples(size_t value)105 void set_generated_noise_samples(size_t value) { 106 generated_noise_samples_ = value; 107 } packet_length_samples()108 size_t packet_length_samples() const { return packet_length_samples_; } set_packet_length_samples(size_t value)109 void set_packet_length_samples(size_t value) { 110 packet_length_samples_ = value; 111 } set_prev_time_scale(bool value)112 void set_prev_time_scale(bool value) { prev_time_scale_ = value; } playout_mode()113 NetEqPlayoutMode playout_mode() const { return playout_mode_; } 114 115 protected: 116 // The value 6 sets maximum time-stretch rate to about 100 ms/s. 117 static const int kMinTimescaleInterval = 6; 118 119 enum CngState { 120 kCngOff, 121 kCngRfc3389On, 122 kCngInternalOn 123 }; 124 125 // Returns the operation that should be done next. |sync_buffer| and |expand| 126 // are provided for reference. |decoder_frame_length| is the number of samples 127 // obtained from the last decoded frame. If there is a packet available, the 128 // packet header should be supplied in |packet_header|; otherwise it should 129 // be NULL. The mode resulting form the last call to NetEqImpl::GetAudio is 130 // supplied in |prev_mode|. If there is a DTMF event to play, |play_dtmf| 131 // should be set to true. The output variable |reset_decoder| will be set to 132 // true if a reset is required; otherwise it is left unchanged (i.e., it can 133 // remain true if it was true before the call). 134 // Should be implemented by derived classes. 135 virtual Operations GetDecisionSpecialized(const SyncBuffer& sync_buffer, 136 const Expand& expand, 137 size_t decoder_frame_length, 138 const RTPHeader* packet_header, 139 Modes prev_mode, 140 bool play_dtmf, 141 bool* reset_decoder) = 0; 142 143 // Updates the |buffer_level_filter_| with the current buffer level 144 // |buffer_size_packets|. 145 void FilterBufferLevel(size_t buffer_size_packets, Modes prev_mode); 146 147 DecoderDatabase* decoder_database_; 148 const PacketBuffer& packet_buffer_; 149 DelayManager* delay_manager_; 150 BufferLevelFilter* buffer_level_filter_; 151 int fs_mult_; 152 size_t output_size_samples_; 153 CngState cng_state_; // Remember if comfort noise is interrupted by other 154 // event (e.g., DTMF). 155 size_t generated_noise_samples_; 156 size_t packet_length_samples_; 157 int sample_memory_; 158 bool prev_time_scale_; 159 int timescale_hold_off_; 160 int num_consecutive_expands_; 161 const NetEqPlayoutMode playout_mode_; 162 163 private: 164 RTC_DISALLOW_COPY_AND_ASSIGN(DecisionLogic); 165 }; 166 167 } // namespace webrtc 168 #endif // WEBRTC_MODULES_AUDIO_CODING_NETEQ_DECISION_LOGIC_H_ 169