1 /*
2  *  Copyright (c) 2004 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 MEDIA_ENGINE_WEBRTC_VOICE_ENGINE_H_
12 #define MEDIA_ENGINE_WEBRTC_VOICE_ENGINE_H_
13 
14 #include <map>
15 #include <memory>
16 #include <string>
17 #include <vector>
18 
19 #include "api/audio_codecs/audio_encoder_factory.h"
20 #include "api/scoped_refptr.h"
21 #include "api/task_queue/task_queue_factory.h"
22 #include "api/transport/rtp/rtp_source.h"
23 #include "call/audio_state.h"
24 #include "call/call.h"
25 #include "media/base/media_engine.h"
26 #include "media/base/rtp_utils.h"
27 #include "rtc_base/buffer.h"
28 #include "rtc_base/constructor_magic.h"
29 #include "rtc_base/network_route.h"
30 #include "rtc_base/task_queue.h"
31 #include "rtc_base/thread_checker.h"
32 
33 namespace cricket {
34 
35 class AudioDeviceModule;
36 class AudioMixer;
37 class AudioSource;
38 class WebRtcVoiceMediaChannel;
39 
40 // WebRtcVoiceEngine is a class to be used with CompositeMediaEngine.
41 // It uses the WebRtc VoiceEngine library for audio handling.
42 class WebRtcVoiceEngine final : public VoiceEngineInterface {
43   friend class WebRtcVoiceMediaChannel;
44 
45  public:
46   WebRtcVoiceEngine(
47       webrtc::TaskQueueFactory* task_queue_factory,
48       webrtc::AudioDeviceModule* adm,
49       const rtc::scoped_refptr<webrtc::AudioEncoderFactory>& encoder_factory,
50       const rtc::scoped_refptr<webrtc::AudioDecoderFactory>& decoder_factory,
51       rtc::scoped_refptr<webrtc::AudioMixer> audio_mixer,
52       rtc::scoped_refptr<webrtc::AudioProcessing> audio_processing);
53   ~WebRtcVoiceEngine() override;
54 
55   // Does initialization that needs to occur on the worker thread.
56   void Init() override;
57 
58   rtc::scoped_refptr<webrtc::AudioState> GetAudioState() const override;
59   VoiceMediaChannel* CreateMediaChannel(
60       webrtc::Call* call,
61       const MediaConfig& config,
62       const AudioOptions& options,
63       const webrtc::CryptoOptions& crypto_options) override;
64 
65   const std::vector<AudioCodec>& send_codecs() const override;
66   const std::vector<AudioCodec>& recv_codecs() const override;
67   std::vector<webrtc::RtpHeaderExtensionCapability> GetRtpHeaderExtensions()
68       const override;
69 
70   // For tracking WebRtc channels. Needed because we have to pause them
71   // all when switching devices.
72   // May only be called by WebRtcVoiceMediaChannel.
73   void RegisterChannel(WebRtcVoiceMediaChannel* channel);
74   void UnregisterChannel(WebRtcVoiceMediaChannel* channel);
75 
76   // Starts AEC dump using an existing file. A maximum file size in bytes can be
77   // specified. When the maximum file size is reached, logging is stopped and
78   // the file is closed. If max_size_bytes is set to <= 0, no limit will be
79   // used.
80   bool StartAecDump(webrtc::FileWrapper file, int64_t max_size_bytes) override;
81 
82   // Stops AEC dump.
83   void StopAecDump() override;
84 
85  private:
86   // Every option that is "set" will be applied. Every option not "set" will be
87   // ignored. This allows us to selectively turn on and off different options
88   // easily at any time.
89   bool ApplyOptions(const AudioOptions& options);
90 
91   int CreateVoEChannel();
92 
93   webrtc::TaskQueueFactory* const task_queue_factory_;
94   std::unique_ptr<rtc::TaskQueue> low_priority_worker_queue_;
95 
96   webrtc::AudioDeviceModule* adm();
97   webrtc::AudioProcessing* apm() const;
98   webrtc::AudioState* audio_state();
99 
100   std::vector<AudioCodec> CollectCodecs(
101       const std::vector<webrtc::AudioCodecSpec>& specs) const;
102 
103   rtc::ThreadChecker signal_thread_checker_;
104   rtc::ThreadChecker worker_thread_checker_;
105 
106   // The audio device module.
107   rtc::scoped_refptr<webrtc::AudioDeviceModule> adm_;
108   rtc::scoped_refptr<webrtc::AudioEncoderFactory> encoder_factory_;
109   rtc::scoped_refptr<webrtc::AudioDecoderFactory> decoder_factory_;
110   rtc::scoped_refptr<webrtc::AudioMixer> audio_mixer_;
111   // The audio processing module.
112   rtc::scoped_refptr<webrtc::AudioProcessing> apm_;
113   // The primary instance of WebRtc VoiceEngine.
114   rtc::scoped_refptr<webrtc::AudioState> audio_state_;
115   std::vector<AudioCodec> send_codecs_;
116   std::vector<AudioCodec> recv_codecs_;
117   std::vector<WebRtcVoiceMediaChannel*> channels_;
118   bool is_dumping_aec_ = false;
119   bool initialized_ = false;
120 
121   // Cache experimental_ns and apply in case they are missing in the audio
122   // options. We need to do this because SetExtraOptions() will revert to
123   // defaults for options which are not provided.
124   absl::optional<bool> experimental_ns_;
125   // Jitter buffer settings for new streams.
126   size_t audio_jitter_buffer_max_packets_ = 200;
127   bool audio_jitter_buffer_fast_accelerate_ = false;
128   int audio_jitter_buffer_min_delay_ms_ = 0;
129   bool audio_jitter_buffer_enable_rtx_handling_ = false;
130 
131   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(WebRtcVoiceEngine);
132 };
133 
134 // WebRtcVoiceMediaChannel is an implementation of VoiceMediaChannel that uses
135 // WebRtc Voice Engine.
136 class WebRtcVoiceMediaChannel final : public VoiceMediaChannel,
137                                       public webrtc::Transport {
138  public:
139   WebRtcVoiceMediaChannel(WebRtcVoiceEngine* engine,
140                           const MediaConfig& config,
141                           const AudioOptions& options,
142                           const webrtc::CryptoOptions& crypto_options,
143                           webrtc::Call* call);
144   ~WebRtcVoiceMediaChannel() override;
145 
options()146   const AudioOptions& options() const { return options_; }
147 
148   bool SetSendParameters(const AudioSendParameters& params) override;
149   bool SetRecvParameters(const AudioRecvParameters& params) override;
150   webrtc::RtpParameters GetRtpSendParameters(uint32_t ssrc) const override;
151   webrtc::RTCError SetRtpSendParameters(
152       uint32_t ssrc,
153       const webrtc::RtpParameters& parameters) override;
154   webrtc::RtpParameters GetRtpReceiveParameters(uint32_t ssrc) const override;
155   webrtc::RtpParameters GetDefaultRtpReceiveParameters() const override;
156 
157   void SetPlayout(bool playout) override;
158   void SetSend(bool send) override;
159   bool SetAudioSend(uint32_t ssrc,
160                     bool enable,
161                     const AudioOptions* options,
162                     AudioSource* source) override;
163   bool AddSendStream(const StreamParams& sp) override;
164   bool RemoveSendStream(uint32_t ssrc) override;
165   bool AddRecvStream(const StreamParams& sp) override;
166   bool RemoveRecvStream(uint32_t ssrc) override;
167   void ResetUnsignaledRecvStream() override;
168 
169   // E2EE Frame API
170   // Set a frame decryptor to a particular ssrc that will intercept all
171   // incoming audio payloads and attempt to decrypt them before forwarding the
172   // result.
173   void SetFrameDecryptor(uint32_t ssrc,
174                          rtc::scoped_refptr<webrtc::FrameDecryptorInterface>
175                              frame_decryptor) override;
176   // Set a frame encryptor to a particular ssrc that will intercept all
177   // outgoing audio payloads frames and attempt to encrypt them and forward the
178   // result to the packetizer.
179   void SetFrameEncryptor(uint32_t ssrc,
180                          rtc::scoped_refptr<webrtc::FrameEncryptorInterface>
181                              frame_encryptor) override;
182 
183   bool SetOutputVolume(uint32_t ssrc, double volume) override;
184   // Applies the new volume to current and future unsignaled streams.
185   bool SetDefaultOutputVolume(double volume) override;
186 
187   bool SetBaseMinimumPlayoutDelayMs(uint32_t ssrc, int delay_ms) override;
188   absl::optional<int> GetBaseMinimumPlayoutDelayMs(
189       uint32_t ssrc) const override;
190 
191   bool CanInsertDtmf() override;
192   bool InsertDtmf(uint32_t ssrc, int event, int duration) override;
193 
194   void OnPacketReceived(rtc::CopyOnWriteBuffer packet,
195                         int64_t packet_time_us) override;
196   void OnNetworkRouteChanged(const std::string& transport_name,
197                              const rtc::NetworkRoute& network_route) override;
198   void OnReadyToSend(bool ready) override;
199   bool GetStats(VoiceMediaInfo* info) override;
200 
201   // Set the audio sink for an existing stream.
202   void SetRawAudioSink(
203       uint32_t ssrc,
204       std::unique_ptr<webrtc::AudioSinkInterface> sink) override;
205   // Will set the audio sink on the latest unsignaled stream, future or
206   // current. Only one stream at a time will use the sink.
207   void SetDefaultRawAudioSink(
208       std::unique_ptr<webrtc::AudioSinkInterface> sink) override;
209 
210   std::vector<webrtc::RtpSource> GetSources(uint32_t ssrc) const override;
211 
212   // Sets a frame transformer between encoder and packetizer, to transform
213   // encoded frames before sending them out the network.
214   void SetEncoderToPacketizerFrameTransformer(
215       uint32_t ssrc,
216       rtc::scoped_refptr<webrtc::FrameTransformerInterface> frame_transformer)
217       override;
218   void SetDepacketizerToDecoderFrameTransformer(
219       uint32_t ssrc,
220       rtc::scoped_refptr<webrtc::FrameTransformerInterface> frame_transformer)
221       override;
222 
223   // implements Transport interface
SendRtp(const uint8_t * data,size_t len,const webrtc::PacketOptions & options)224   bool SendRtp(const uint8_t* data,
225                size_t len,
226                const webrtc::PacketOptions& options) override {
227     rtc::CopyOnWriteBuffer packet(data, len, kMaxRtpPacketLen);
228     rtc::PacketOptions rtc_options;
229     rtc_options.packet_id = options.packet_id;
230     if (DscpEnabled()) {
231       rtc_options.dscp = PreferredDscp();
232     }
233     rtc_options.info_signaled_after_sent.included_in_feedback =
234         options.included_in_feedback;
235     rtc_options.info_signaled_after_sent.included_in_allocation =
236         options.included_in_allocation;
237     return VoiceMediaChannel::SendPacket(&packet, rtc_options);
238   }
239 
SendRtcp(const uint8_t * data,size_t len)240   bool SendRtcp(const uint8_t* data, size_t len) override {
241     rtc::CopyOnWriteBuffer packet(data, len, kMaxRtpPacketLen);
242     rtc::PacketOptions rtc_options;
243     if (DscpEnabled()) {
244       rtc_options.dscp = PreferredDscp();
245     }
246 
247     return VoiceMediaChannel::SendRtcp(&packet, rtc_options);
248   }
249 
250  private:
251   bool SetOptions(const AudioOptions& options);
252   bool SetRecvCodecs(const std::vector<AudioCodec>& codecs);
253   bool SetSendCodecs(const std::vector<AudioCodec>& codecs);
254   bool SetLocalSource(uint32_t ssrc, AudioSource* source);
255   bool MuteStream(uint32_t ssrc, bool mute);
256 
engine()257   WebRtcVoiceEngine* engine() { return engine_; }
258   void ChangePlayout(bool playout);
259   int CreateVoEChannel();
260   bool DeleteVoEChannel(int channel);
261   bool SetMaxSendBitrate(int bps);
262   void SetupRecording();
263   // Check if 'ssrc' is an unsignaled stream, and if so mark it as not being
264   // unsignaled anymore (i.e. it is now removed, or signaled), and return true.
265   bool MaybeDeregisterUnsignaledRecvStream(uint32_t ssrc);
266 
267   rtc::ThreadChecker worker_thread_checker_;
268 
269   WebRtcVoiceEngine* const engine_ = nullptr;
270   std::vector<AudioCodec> send_codecs_;
271 
272   // TODO(kwiberg): decoder_map_ and recv_codecs_ store the exact same
273   // information, in slightly different formats. Eliminate recv_codecs_.
274   std::map<int, webrtc::SdpAudioFormat> decoder_map_;
275   std::vector<AudioCodec> recv_codecs_;
276 
277   int max_send_bitrate_bps_ = 0;
278   AudioOptions options_;
279   absl::optional<int> dtmf_payload_type_;
280   int dtmf_payload_freq_ = -1;
281   bool recv_transport_cc_enabled_ = false;
282   bool recv_nack_enabled_ = false;
283   bool desired_playout_ = false;
284   bool playout_ = false;
285   bool send_ = false;
286   webrtc::Call* const call_ = nullptr;
287 
288   const MediaConfig::Audio audio_config_;
289 
290   // Queue of unsignaled SSRCs; oldest at the beginning.
291   std::vector<uint32_t> unsignaled_recv_ssrcs_;
292 
293   // This is a stream param that comes from the remote description, but wasn't
294   // signaled with any a=ssrc lines. It holds the information that was signaled
295   // before the unsignaled receive stream is created when the first packet is
296   // received.
297   StreamParams unsignaled_stream_params_;
298 
299   // Volume for unsignaled streams, which may be set before the stream exists.
300   double default_recv_volume_ = 1.0;
301 
302   // Delay for unsignaled streams, which may be set before the stream exists.
303   int default_recv_base_minimum_delay_ms_ = 0;
304 
305   // Sink for latest unsignaled stream - may be set before the stream exists.
306   std::unique_ptr<webrtc::AudioSinkInterface> default_sink_;
307   // Default SSRC to use for RTCP receiver reports in case of no signaled
308   // send streams. See: https://code.google.com/p/webrtc/issues/detail?id=4740
309   // and https://code.google.com/p/chromium/issues/detail?id=547661
310   uint32_t receiver_reports_ssrc_ = 0xFA17FA17u;
311 
312   class WebRtcAudioSendStream;
313   std::map<uint32_t, WebRtcAudioSendStream*> send_streams_;
314   std::vector<webrtc::RtpExtension> send_rtp_extensions_;
315   std::string mid_;
316 
317   class WebRtcAudioReceiveStream;
318   std::map<uint32_t, WebRtcAudioReceiveStream*> recv_streams_;
319   std::vector<webrtc::RtpExtension> recv_rtp_extensions_;
320 
321   absl::optional<webrtc::AudioSendStream::Config::SendCodecSpec>
322       send_codec_spec_;
323 
324   // TODO(kwiberg): Per-SSRC codec pair IDs?
325   const webrtc::AudioCodecPairId codec_pair_id_ =
326       webrtc::AudioCodecPairId::Create();
327 
328   // Per peer connection crypto options that last for the lifetime of the peer
329   // connection.
330   const webrtc::CryptoOptions crypto_options_;
331   // Unsignaled streams have an option to have a frame decryptor set on them.
332   rtc::scoped_refptr<webrtc::FrameDecryptorInterface>
333       unsignaled_frame_decryptor_;
334 
335   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(WebRtcVoiceMediaChannel);
336 };
337 }  // namespace cricket
338 
339 #endif  // MEDIA_ENGINE_WEBRTC_VOICE_ENGINE_H_
340