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 #include "webrtc/modules/audio_coding/neteq/decision_logic.h"
12
13 #include <algorithm>
14
15 #include "webrtc/modules/audio_coding/neteq/buffer_level_filter.h"
16 #include "webrtc/modules/audio_coding/neteq/decision_logic_fax.h"
17 #include "webrtc/modules/audio_coding/neteq/decision_logic_normal.h"
18 #include "webrtc/modules/audio_coding/neteq/delay_manager.h"
19 #include "webrtc/modules/audio_coding/neteq/expand.h"
20 #include "webrtc/modules/audio_coding/neteq/packet_buffer.h"
21 #include "webrtc/modules/audio_coding/neteq/sync_buffer.h"
22 #include "webrtc/system_wrappers/include/logging.h"
23
24 namespace webrtc {
25
Create(int fs_hz,size_t output_size_samples,NetEqPlayoutMode playout_mode,DecoderDatabase * decoder_database,const PacketBuffer & packet_buffer,DelayManager * delay_manager,BufferLevelFilter * buffer_level_filter)26 DecisionLogic* DecisionLogic::Create(int fs_hz,
27 size_t output_size_samples,
28 NetEqPlayoutMode playout_mode,
29 DecoderDatabase* decoder_database,
30 const PacketBuffer& packet_buffer,
31 DelayManager* delay_manager,
32 BufferLevelFilter* buffer_level_filter) {
33 switch (playout_mode) {
34 case kPlayoutOn:
35 case kPlayoutStreaming:
36 return new DecisionLogicNormal(fs_hz,
37 output_size_samples,
38 playout_mode,
39 decoder_database,
40 packet_buffer,
41 delay_manager,
42 buffer_level_filter);
43 case kPlayoutFax:
44 case kPlayoutOff:
45 return new DecisionLogicFax(fs_hz,
46 output_size_samples,
47 playout_mode,
48 decoder_database,
49 packet_buffer,
50 delay_manager,
51 buffer_level_filter);
52 }
53 // This line cannot be reached, but must be here to avoid compiler errors.
54 assert(false);
55 return NULL;
56 }
57
DecisionLogic(int fs_hz,size_t output_size_samples,NetEqPlayoutMode playout_mode,DecoderDatabase * decoder_database,const PacketBuffer & packet_buffer,DelayManager * delay_manager,BufferLevelFilter * buffer_level_filter)58 DecisionLogic::DecisionLogic(int fs_hz,
59 size_t output_size_samples,
60 NetEqPlayoutMode playout_mode,
61 DecoderDatabase* decoder_database,
62 const PacketBuffer& packet_buffer,
63 DelayManager* delay_manager,
64 BufferLevelFilter* buffer_level_filter)
65 : decoder_database_(decoder_database),
66 packet_buffer_(packet_buffer),
67 delay_manager_(delay_manager),
68 buffer_level_filter_(buffer_level_filter),
69 cng_state_(kCngOff),
70 generated_noise_samples_(0),
71 packet_length_samples_(0),
72 sample_memory_(0),
73 prev_time_scale_(false),
74 timescale_hold_off_(kMinTimescaleInterval),
75 num_consecutive_expands_(0),
76 playout_mode_(playout_mode) {
77 delay_manager_->set_streaming_mode(playout_mode_ == kPlayoutStreaming);
78 SetSampleRate(fs_hz, output_size_samples);
79 }
80
Reset()81 void DecisionLogic::Reset() {
82 cng_state_ = kCngOff;
83 generated_noise_samples_ = 0;
84 packet_length_samples_ = 0;
85 sample_memory_ = 0;
86 prev_time_scale_ = false;
87 timescale_hold_off_ = 0;
88 num_consecutive_expands_ = 0;
89 }
90
SoftReset()91 void DecisionLogic::SoftReset() {
92 packet_length_samples_ = 0;
93 sample_memory_ = 0;
94 prev_time_scale_ = false;
95 timescale_hold_off_ = kMinTimescaleInterval;
96 }
97
SetSampleRate(int fs_hz,size_t output_size_samples)98 void DecisionLogic::SetSampleRate(int fs_hz, size_t output_size_samples) {
99 // TODO(hlundin): Change to an enumerator and skip assert.
100 assert(fs_hz == 8000 || fs_hz == 16000 || fs_hz == 32000 || fs_hz == 48000);
101 fs_mult_ = fs_hz / 8000;
102 output_size_samples_ = output_size_samples;
103 }
104
GetDecision(const SyncBuffer & sync_buffer,const Expand & expand,size_t decoder_frame_length,const RTPHeader * packet_header,Modes prev_mode,bool play_dtmf,bool * reset_decoder)105 Operations DecisionLogic::GetDecision(const SyncBuffer& sync_buffer,
106 const Expand& expand,
107 size_t decoder_frame_length,
108 const RTPHeader* packet_header,
109 Modes prev_mode,
110 bool play_dtmf, bool* reset_decoder) {
111 if (prev_mode == kModeRfc3389Cng ||
112 prev_mode == kModeCodecInternalCng ||
113 prev_mode == kModeExpand) {
114 // If last mode was CNG (or Expand, since this could be covering up for
115 // a lost CNG packet), increase the |generated_noise_samples_| counter.
116 generated_noise_samples_ += output_size_samples_;
117 // Remember that CNG is on. This is needed if comfort noise is interrupted
118 // by DTMF.
119 if (prev_mode == kModeRfc3389Cng) {
120 cng_state_ = kCngRfc3389On;
121 } else if (prev_mode == kModeCodecInternalCng) {
122 cng_state_ = kCngInternalOn;
123 }
124 }
125
126 const size_t samples_left =
127 sync_buffer.FutureLength() - expand.overlap_length();
128 const size_t cur_size_samples =
129 samples_left + packet_buffer_.NumSamplesInBuffer(decoder_database_,
130 decoder_frame_length);
131
132 prev_time_scale_ = prev_time_scale_ &&
133 (prev_mode == kModeAccelerateSuccess ||
134 prev_mode == kModeAccelerateLowEnergy ||
135 prev_mode == kModePreemptiveExpandSuccess ||
136 prev_mode == kModePreemptiveExpandLowEnergy);
137
138 FilterBufferLevel(cur_size_samples, prev_mode);
139
140 return GetDecisionSpecialized(sync_buffer, expand, decoder_frame_length,
141 packet_header, prev_mode, play_dtmf,
142 reset_decoder);
143 }
144
ExpandDecision(Operations operation)145 void DecisionLogic::ExpandDecision(Operations operation) {
146 if (operation == kExpand) {
147 num_consecutive_expands_++;
148 } else {
149 num_consecutive_expands_ = 0;
150 }
151 }
152
FilterBufferLevel(size_t buffer_size_samples,Modes prev_mode)153 void DecisionLogic::FilterBufferLevel(size_t buffer_size_samples,
154 Modes prev_mode) {
155 const int elapsed_time_ms =
156 static_cast<int>(output_size_samples_ / (8 * fs_mult_));
157 delay_manager_->UpdateCounters(elapsed_time_ms);
158
159 // Do not update buffer history if currently playing CNG since it will bias
160 // the filtered buffer level.
161 if ((prev_mode != kModeRfc3389Cng) && (prev_mode != kModeCodecInternalCng)) {
162 buffer_level_filter_->SetTargetBufferLevel(
163 delay_manager_->base_target_level());
164
165 size_t buffer_size_packets = 0;
166 if (packet_length_samples_ > 0) {
167 // Calculate size in packets.
168 buffer_size_packets = buffer_size_samples / packet_length_samples_;
169 }
170 int sample_memory_local = 0;
171 if (prev_time_scale_) {
172 sample_memory_local = sample_memory_;
173 timescale_hold_off_ = kMinTimescaleInterval;
174 }
175 buffer_level_filter_->Update(buffer_size_packets, sample_memory_local,
176 packet_length_samples_);
177 prev_time_scale_ = false;
178 }
179
180 timescale_hold_off_ = std::max(timescale_hold_off_ - 1, 0);
181 }
182
183 } // namespace webrtc
184