2 #define _AUDIO_MIXER_H 1
4 // The audio mixer, dealing with extracting the right signals from
5 // each capture card, resampling signals so that they are in sync,
6 // processing them with effects (if desired), and then mixing them
7 // all together into one final audio signal.
9 // All operations on AudioMixer (except destruction) are thread-safe.
19 #include <zita-resampler/resampler.h>
21 #include "alsa_input.h"
22 #include "bmusb/bmusb.h"
23 #include "correlation_measurer.h"
26 #include "ebu_r128_proc.h"
28 #include "input_mapping.h"
29 #include "resampling_queue.h"
30 #include "stereocompressor.h"
45 AudioMixer(unsigned num_cards);
46 void reset_resampler(DeviceSpec device_spec);
49 // Add audio (or silence) to the given device's queue. Can return false if
50 // the lock wasn't successfully taken; if so, you should simply try again.
51 // (This is to avoid a deadlock where a card hangs on the mutex in add_audio()
52 // while we are trying to shut it down from another thread that also holds
53 // the mutex.) frame_length is in TIMEBASE units.
54 bool add_audio(DeviceSpec device_spec, const uint8_t *data, unsigned num_samples, bmusb::AudioFormat audio_format, int64_t frame_length);
55 bool add_silence(DeviceSpec device_spec, unsigned samples_per_frame, unsigned num_frames, int64_t frame_length);
57 // If a given device is offline for whatever reason and cannot deliver audio
58 // (by means of add_audio() or add_silence()), you can call put it in silence mode,
59 // where it will be taken to only output silence. Note that when taking it _out_
60 // of silence mode, the resampler will be reset, so that old audio will not
61 // affect it. Same true/false behavior as add_audio().
62 bool silence_card(DeviceSpec device_spec, bool silence);
64 std::vector<float> get_output(double pts, unsigned num_samples, ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy);
66 float get_fader_volume(unsigned bus_index) const { return fader_volume_db[bus_index]; }
67 void set_fader_volume(unsigned bus_index, float level_db) { fader_volume_db[bus_index] = level_db; }
69 // Note: This operation holds all ALSA devices (see ALSAPool::get_devices()).
70 // You will need to call set_input_mapping() to get the hold state correctly,
71 // or every card will be held forever.
72 std::map<DeviceSpec, DeviceInfo> get_devices();
74 // See comments on ALSAPool::get_card_state().
75 ALSAPool::Device::State get_alsa_card_state(unsigned index)
77 return alsa_pool.get_card_state(index);
80 // See comments on ALSAPool::create_dead_card().
81 DeviceSpec create_dead_card(const std::string &name, const std::string &info, unsigned num_channels)
83 unsigned dead_card_index = alsa_pool.create_dead_card(name, info, num_channels);
84 return DeviceSpec{InputSourceType::ALSA_INPUT, dead_card_index};
87 void set_display_name(DeviceSpec device_spec, const std::string &name);
89 // Note: The card should be held (currently this isn't enforced, though).
90 void serialize_device(DeviceSpec device_spec, DeviceSpecProto *device_spec_proto);
92 void set_input_mapping(const InputMapping &input_mapping);
93 InputMapping get_input_mapping() const;
95 void set_locut_cutoff(float cutoff_hz)
97 locut_cutoff_hz = cutoff_hz;
100 float get_locut_cutoff() const
102 return locut_cutoff_hz;
105 void set_locut_enabled(unsigned bus, bool enabled)
107 locut_enabled[bus] = enabled;
110 bool get_locut_enabled(unsigned bus)
112 return locut_enabled[bus];
115 void set_eq(unsigned bus_index, EQBand band, float db_gain)
117 assert(band >= 0 && band < NUM_EQ_BANDS);
118 eq_level_db[bus_index][band] = db_gain;
121 float get_eq(unsigned bus_index, EQBand band) const
123 assert(band >= 0 && band < NUM_EQ_BANDS);
124 return eq_level_db[bus_index][band];
127 float get_limiter_threshold_dbfs() const
129 return limiter_threshold_dbfs;
132 float get_compressor_threshold_dbfs(unsigned bus_index) const
134 return compressor_threshold_dbfs[bus_index];
137 void set_limiter_threshold_dbfs(float threshold_dbfs)
139 limiter_threshold_dbfs = threshold_dbfs;
142 void set_compressor_threshold_dbfs(unsigned bus_index, float threshold_dbfs)
144 compressor_threshold_dbfs[bus_index] = threshold_dbfs;
147 void set_limiter_enabled(bool enabled)
149 limiter_enabled = enabled;
152 bool get_limiter_enabled() const
154 return limiter_enabled;
157 void set_compressor_enabled(unsigned bus_index, bool enabled)
159 compressor_enabled[bus_index] = enabled;
162 bool get_compressor_enabled(unsigned bus_index) const
164 return compressor_enabled[bus_index];
167 void set_gain_staging_db(unsigned bus_index, float gain_db)
169 std::unique_lock<std::mutex> lock(compressor_mutex);
170 level_compressor_enabled[bus_index] = false;
171 gain_staging_db[bus_index] = gain_db;
174 float get_gain_staging_db(unsigned bus_index) const
176 std::unique_lock<std::mutex> lock(compressor_mutex);
177 return gain_staging_db[bus_index];
180 void set_gain_staging_auto(unsigned bus_index, bool enabled)
182 std::unique_lock<std::mutex> lock(compressor_mutex);
183 level_compressor_enabled[bus_index] = enabled;
186 bool get_gain_staging_auto(unsigned bus_index) const
188 std::unique_lock<std::mutex> lock(compressor_mutex);
189 return level_compressor_enabled[bus_index];
192 void set_final_makeup_gain_db(float gain_db)
194 std::unique_lock<std::mutex> lock(compressor_mutex);
195 final_makeup_gain_auto = false;
196 final_makeup_gain = from_db(gain_db);
199 float get_final_makeup_gain_db()
201 std::unique_lock<std::mutex> lock(compressor_mutex);
202 return to_db(final_makeup_gain);
205 void set_final_makeup_gain_auto(bool enabled)
207 std::unique_lock<std::mutex> lock(compressor_mutex);
208 final_makeup_gain_auto = enabled;
211 bool get_final_makeup_gain_auto() const
213 std::unique_lock<std::mutex> lock(compressor_mutex);
214 return final_makeup_gain_auto;
217 void reset_peak(unsigned bus_index);
220 float current_level_dbfs[2]; // Digital peak of last frame, left and right.
221 float peak_level_dbfs[2]; // Digital peak with hold, left and right.
222 float historic_peak_dbfs;
223 float gain_staging_db;
224 float compressor_attenuation_db; // A positive number; 0.0 for no attenuation.
227 typedef std::function<void(float level_lufs, float peak_db,
228 std::vector<BusLevel> bus_levels,
229 float global_level_lufs, float range_low_lufs, float range_high_lufs,
230 float final_makeup_gain_db,
231 float correlation)> audio_level_callback_t;
232 void set_audio_level_callback(audio_level_callback_t callback)
234 audio_level_callback = callback;
237 typedef std::function<void()> state_changed_callback_t;
238 void set_state_changed_callback(state_changed_callback_t callback)
240 state_changed_callback = callback;
243 state_changed_callback_t get_state_changed_callback() const
245 return state_changed_callback;
248 void trigger_state_changed_callback()
250 if (state_changed_callback != nullptr) {
251 state_changed_callback();
255 // A combination of all settings for a bus. Useful if you want to get
256 // or store them as a whole without bothering to call all of the get_*
257 // or set_* functions for that bus.
259 float fader_volume_db;
261 float eq_level_db[NUM_EQ_BANDS];
262 float gain_staging_db;
263 bool level_compressor_enabled;
264 float compressor_threshold_dbfs;
265 bool compressor_enabled;
267 static BusSettings get_default_bus_settings();
268 BusSettings get_bus_settings(unsigned bus_index) const;
269 void set_bus_settings(unsigned bus_index, const BusSettings &settings);
273 std::unique_ptr<ResamplingQueue> resampling_queue;
274 int64_t next_local_pts = 0;
275 std::string display_name;
276 unsigned capture_frequency = OUTPUT_FREQUENCY;
277 // Which channels we consider interesting (ie., are part of some input_mapping).
278 std::set<unsigned> interesting_channels;
279 bool silenced = false;
282 const AudioDevice *find_audio_device(DeviceSpec device_spec) const
284 return const_cast<AudioMixer *>(this)->find_audio_device(device_spec);
287 AudioDevice *find_audio_device(DeviceSpec device_spec);
289 void find_sample_src_from_device(const std::map<DeviceSpec, std::vector<float>> &samples_card, DeviceSpec device_spec, int source_channel, const float **srcptr, unsigned *stride);
290 void fill_audio_bus(const std::map<DeviceSpec, std::vector<float>> &samples_card, const InputMapping::Bus &bus, unsigned num_samples, float *output);
291 void reset_resampler_mutex_held(DeviceSpec device_spec);
292 void apply_eq(unsigned bus_index, std::vector<float> *samples_bus);
293 void update_meters(const std::vector<float> &samples);
294 void add_bus_to_master(unsigned bus_index, const std::vector<float> &samples_bus, std::vector<float> *samples_out);
295 void measure_bus_levels(unsigned bus_index, const std::vector<float> &left, const std::vector<float> &right);
296 void send_audio_level_callback();
297 std::vector<DeviceSpec> get_active_devices() const;
301 mutable std::timed_mutex audio_mutex;
304 AudioDevice video_cards[MAX_VIDEO_CARDS]; // Under audio_mutex.
305 AudioDevice alsa_inputs[MAX_ALSA_CARDS]; // Under audio_mutex.
307 std::atomic<float> locut_cutoff_hz{120};
308 StereoFilter locut[MAX_BUSES]; // Default cutoff 120 Hz, 24 dB/oct.
309 std::atomic<bool> locut_enabled[MAX_BUSES];
310 StereoFilter eq[MAX_BUSES][NUM_EQ_BANDS]; // The one for EQBand::MID isn't actually used (see comments in apply_eq()).
312 // First compressor; takes us up to about -12 dBFS.
313 mutable std::mutex compressor_mutex;
314 std::unique_ptr<StereoCompressor> level_compressor[MAX_BUSES]; // Under compressor_mutex. Used to set/override gain_staging_db if <level_compressor_enabled>.
315 float gain_staging_db[MAX_BUSES]; // Under compressor_mutex.
316 bool level_compressor_enabled[MAX_BUSES]; // Under compressor_mutex.
318 static constexpr float ref_level_dbfs = -14.0f; // Chosen so that we end up around 0 LU in practice.
319 static constexpr float ref_level_lufs = -23.0f; // 0 LU, more or less by definition.
321 StereoCompressor limiter;
322 std::atomic<float> limiter_threshold_dbfs{ref_level_dbfs + 4.0f}; // 4 dB.
323 std::atomic<bool> limiter_enabled{true};
324 std::unique_ptr<StereoCompressor> compressor[MAX_BUSES];
325 std::atomic<float> compressor_threshold_dbfs[MAX_BUSES];
326 std::atomic<bool> compressor_enabled[MAX_BUSES];
328 // Note: The values here are not in dB.
330 float current_level = 0.0f; // Peak of the last frame.
331 float historic_peak = 0.0f; // Highest peak since last reset; no falloff.
332 float current_peak = 0.0f; // Current peak of the peak meter.
333 float last_peak = 0.0f;
334 float age_seconds = 0.0f; // Time since "last_peak" was set.
336 PeakHistory peak_history[MAX_BUSES][2]; // Separate for each channel. Under audio_mutex.
338 double final_makeup_gain = 1.0; // Under compressor_mutex. Read/write by the user. Note: Not in dB, we want the numeric precision so that we can change it slowly.
339 bool final_makeup_gain_auto = true; // Under compressor_mutex.
341 InputMapping input_mapping; // Under audio_mutex.
342 std::atomic<float> fader_volume_db[MAX_BUSES] {{ 0.0f }};
343 float last_fader_volume_db[MAX_BUSES] { 0.0f }; // Under audio_mutex.
344 std::atomic<float> eq_level_db[MAX_BUSES][NUM_EQ_BANDS] {{{ 0.0f }}};
346 audio_level_callback_t audio_level_callback = nullptr;
347 state_changed_callback_t state_changed_callback = nullptr;
348 mutable std::mutex audio_measure_mutex;
349 Ebu_r128_proc r128; // Under audio_measure_mutex.
350 CorrelationMeasurer correlation; // Under audio_measure_mutex.
351 Resampler peak_resampler; // Under audio_measure_mutex.
352 std::atomic<float> peak{0.0f};
355 extern AudioMixer *global_audio_mixer;
357 #endif // !defined(_AUDIO_MIXER_H)