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.
13 #include <zita-resampler/resampler.h>
24 #include "alsa_pool.h"
25 #include "card_type.h"
26 #include "correlation_measurer.h"
29 #include "ebu_r128_proc.h"
31 #include "input_mapping.h"
32 #include "resampling_queue.h"
33 #include "stereocompressor.h"
35 class DeviceSpecProto;
41 // Convert the given audio from {16,24,32}-bit M-channel to 32-bit N-channel PCM.
42 // Assumes little-endian and chunky, signed PCM throughout.
43 std::vector<int32_t> convert_audio_to_fixed32(const uint8_t *data, unsigned num_samples, bmusb::AudioFormat audio_format, unsigned num_destination_channels);
55 void reset_resampler(DeviceSpec device_spec);
58 // Add audio (or silence) to the given device's queue. Can return false if
59 // the lock wasn't successfully taken; if so, you should simply try again.
60 // (This is to avoid a deadlock where a card hangs on the mutex in add_audio()
61 // while we are trying to shut it down from another thread that also holds
63 bool add_audio(DeviceSpec device_spec, const uint8_t *data, unsigned num_samples, bmusb::AudioFormat audio_format, std::chrono::steady_clock::time_point frame_time);
64 bool add_silence(DeviceSpec device_spec, unsigned samples_per_frame, unsigned num_frames);
66 // If a given device is offline for whatever reason and cannot deliver audio
67 // (by means of add_audio() or add_silence()), you can call put it in silence mode,
68 // where it will be taken to only output silence. Note that when taking it _out_
69 // of silence mode, the resampler will be reset, so that old audio will not
70 // affect it. Same true/false behavior as add_audio().
71 bool silence_card(DeviceSpec device_spec, bool silence);
73 std::vector<float> get_output(std::chrono::steady_clock::time_point ts, unsigned num_samples, ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy);
75 float get_fader_volume(unsigned bus_index) const { return fader_volume_db[bus_index]; }
76 void set_fader_volume(unsigned bus_index, float level_db) { fader_volume_db[bus_index] = level_db; }
78 bool get_mute(unsigned bus_index) const { return mute[bus_index]; }
79 void set_mute(unsigned bus_index, bool muted) { mute[bus_index] = muted; }
81 // Note: This operation holds all ALSA devices (see ALSAPool::get_devices()).
82 // You will need to call set_input_mapping() to get the hold state correctly,
83 // or every card will be held forever.
84 std::map<DeviceSpec, DeviceInfo> get_devices();
86 // See comments on ALSAPool::get_card_state().
87 ALSAPool::Device::State get_alsa_card_state(unsigned index)
89 return alsa_pool.get_card_state(index);
92 // See comments on ALSAPool::create_dead_card().
93 DeviceSpec create_dead_card(const std::string &name, const std::string &info, unsigned num_channels)
95 unsigned dead_card_index = alsa_pool.create_dead_card(name, info, num_channels);
96 return DeviceSpec{InputSourceType::ALSA_INPUT, dead_card_index};
99 // NOTE: The display name is not overridden if active == false.
100 void set_device_parameters(DeviceSpec device_spec, const std::string &display_name, CardType card_type, unsigned num_channels, bool active);
101 bool get_active(DeviceSpec device_spec);
103 // Note: The card should be held (currently this isn't enforced, though).
104 void serialize_device(DeviceSpec device_spec, DeviceSpecProto *device_spec_proto);
106 enum class MappingMode {
107 // A single bus, only from a video card (no ALSA devices),
108 // only channel 1 and 2, locked to +0 dB. Note that this is
109 // only an UI abstraction around exactly the same audio code
110 // as MULTICHANNEL; it's just less flexible.
113 // Full, arbitrary mappings.
117 // Automatically sets mapping mode to MappingMode::SIMPLE.
118 void set_simple_input(unsigned card_index);
120 // If mapping mode is not representable as a MappingMode::SIMPLE type
121 // mapping, returns numeric_limits<unsigned>::max().
122 unsigned get_simple_input() const;
124 // Implicitly sets mapping mode to MappingMode::MULTICHANNEL.
125 void set_input_mapping(const InputMapping &input_mapping);
127 MappingMode get_mapping_mode() const;
128 InputMapping get_input_mapping() const;
130 unsigned num_buses() const;
132 void set_locut_cutoff(float cutoff_hz)
134 locut_cutoff_hz = cutoff_hz;
137 float get_locut_cutoff() const
139 return locut_cutoff_hz;
142 void set_locut_enabled(unsigned bus, bool enabled)
144 locut_enabled[bus] = enabled;
147 bool get_locut_enabled(unsigned bus)
149 return locut_enabled[bus];
152 bool is_mono(unsigned bus_index);
154 void set_stereo_width(unsigned bus_index, float width)
156 stereo_width[bus_index] = width;
159 float get_stereo_width(unsigned bus_index)
161 return stereo_width[bus_index];
164 void set_eq(unsigned bus_index, EQBand band, float db_gain)
166 assert(band >= 0 && band < NUM_EQ_BANDS);
167 eq_level_db[bus_index][band] = db_gain;
170 float get_eq(unsigned bus_index, EQBand band) const
172 assert(band >= 0 && band < NUM_EQ_BANDS);
173 return eq_level_db[bus_index][band];
176 float get_limiter_threshold_dbfs() const
178 return limiter_threshold_dbfs;
181 float get_compressor_threshold_dbfs(unsigned bus_index) const
183 return compressor_threshold_dbfs[bus_index];
186 void set_limiter_threshold_dbfs(float threshold_dbfs)
188 limiter_threshold_dbfs = threshold_dbfs;
191 void set_compressor_threshold_dbfs(unsigned bus_index, float threshold_dbfs)
193 compressor_threshold_dbfs[bus_index] = threshold_dbfs;
196 void set_limiter_enabled(bool enabled)
198 limiter_enabled = enabled;
201 bool get_limiter_enabled() const
203 return limiter_enabled;
206 void set_compressor_enabled(unsigned bus_index, bool enabled)
208 compressor_enabled[bus_index] = enabled;
211 bool get_compressor_enabled(unsigned bus_index) const
213 return compressor_enabled[bus_index];
216 void set_gain_staging_db(unsigned bus_index, float gain_db)
218 std::lock_guard<std::mutex> lock(compressor_mutex);
219 level_compressor_enabled[bus_index] = false;
220 gain_staging_db[bus_index] = gain_db;
223 float get_gain_staging_db(unsigned bus_index) const
225 std::lock_guard<std::mutex> lock(compressor_mutex);
226 return gain_staging_db[bus_index];
229 void set_gain_staging_auto(unsigned bus_index, bool enabled)
231 std::lock_guard<std::mutex> lock(compressor_mutex);
232 level_compressor_enabled[bus_index] = enabled;
235 bool get_gain_staging_auto(unsigned bus_index) const
237 std::lock_guard<std::mutex> lock(compressor_mutex);
238 return level_compressor_enabled[bus_index];
241 void set_final_makeup_gain_db(float gain_db)
243 std::lock_guard<std::mutex> lock(compressor_mutex);
244 final_makeup_gain_auto = false;
245 final_makeup_gain = from_db(gain_db);
248 float get_final_makeup_gain_db()
250 std::lock_guard<std::mutex> lock(compressor_mutex);
251 return to_db(final_makeup_gain);
254 void set_final_makeup_gain_auto(bool enabled)
256 std::lock_guard<std::mutex> lock(compressor_mutex);
257 final_makeup_gain_auto = enabled;
260 bool get_final_makeup_gain_auto() const
262 std::lock_guard<std::mutex> lock(compressor_mutex);
263 return final_makeup_gain_auto;
266 void reset_peak(unsigned bus_index);
269 float current_level_dbfs[2]; // Digital peak of last frame, left and right.
270 float peak_level_dbfs[2]; // Digital peak with hold, left and right.
271 float historic_peak_dbfs;
272 float gain_staging_db;
273 float compressor_attenuation_db; // A positive number; 0.0 for no attenuation.
276 typedef std::function<void(float level_lufs, float peak_db,
277 std::vector<BusLevel> bus_levels,
278 float global_level_lufs, float range_low_lufs, float range_high_lufs,
279 float final_makeup_gain_db,
280 float correlation)> audio_level_callback_t;
281 void set_audio_level_callback(audio_level_callback_t callback)
283 audio_level_callback = callback;
286 typedef std::function<void()> state_changed_callback_t;
287 void set_state_changed_callback(state_changed_callback_t callback)
289 state_changed_callback = callback;
292 state_changed_callback_t get_state_changed_callback() const
294 return state_changed_callback;
297 void trigger_state_changed_callback()
299 if (state_changed_callback != nullptr) {
300 state_changed_callback();
304 // A combination of all settings for a bus. Useful if you want to get
305 // or store them as a whole without bothering to call all of the get_*
306 // or set_* functions for that bus.
308 float fader_volume_db;
312 float eq_level_db[NUM_EQ_BANDS];
313 float gain_staging_db;
314 bool level_compressor_enabled;
315 float compressor_threshold_dbfs;
316 bool compressor_enabled;
318 static BusSettings get_default_bus_settings();
319 BusSettings get_bus_settings(unsigned bus_index) const;
320 void set_bus_settings(unsigned bus_index, const BusSettings &settings);
324 std::unique_ptr<ResamplingQueue> resampling_queue;
325 std::string display_name;
326 unsigned capture_frequency = OUTPUT_FREQUENCY;
327 // Which channels we consider interesting (ie., are part of some input_mapping).
328 std::set<unsigned> interesting_channels;
329 bool silenced = false;
331 unsigned num_channels = 2; // Ignored for ALSA cards, which check the device directly.
332 bool active = false; // Only really relevant for capture cards (not ALSA cards).
335 const AudioDevice *find_audio_device(DeviceSpec device_spec) const
337 return const_cast<AudioMixer *>(this)->find_audio_device(device_spec);
340 AudioDevice *find_audio_device(DeviceSpec device_spec);
342 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);
343 void fill_audio_bus(const std::map<DeviceSpec, std::vector<float>> &samples_card, const InputMapping::Bus &bus, unsigned num_samples, float stereo_width, float *output);
344 void reset_resampler_mutex_held(DeviceSpec device_spec);
345 void apply_eq(unsigned bus_index, std::vector<float> *samples_bus);
346 void update_meters(const std::vector<float> &samples);
347 void add_bus_to_master(unsigned bus_index, const std::vector<float> &samples_bus, std::vector<float> *samples_out);
348 void measure_bus_levels(unsigned bus_index, const std::vector<float> &left, const std::vector<float> &right);
349 void send_audio_level_callback();
350 std::vector<DeviceSpec> get_active_devices() const;
351 void set_input_mapping_lock_held(const InputMapping &input_mapping);
352 std::string spec_to_string(DeviceSpec device_spec) const;
354 mutable std::timed_mutex audio_mutex;
357 AudioDevice video_cards[MAX_VIDEO_CARDS]; // Under audio_mutex.
358 AudioDevice alsa_inputs[MAX_ALSA_CARDS]; // Under audio_mutex.
360 std::atomic<float> locut_cutoff_hz{120};
361 StereoFilter locut[MAX_BUSES]; // Default cutoff 120 Hz, 24 dB/oct.
362 std::atomic<bool> locut_enabled[MAX_BUSES];
363 StereoFilter eq[MAX_BUSES][NUM_EQ_BANDS]; // The one for EQBand::MID isn't actually used (see comments in apply_eq()).
365 // First compressor; takes us up to about -12 dBFS.
366 mutable std::mutex compressor_mutex;
367 std::unique_ptr<StereoCompressor> level_compressor[MAX_BUSES]; // Under compressor_mutex. Used to set/override gain_staging_db if <level_compressor_enabled>.
368 float gain_staging_db[MAX_BUSES]; // Under compressor_mutex.
369 float last_gain_staging_db[MAX_BUSES]; // Under compressor_mutex.
370 bool level_compressor_enabled[MAX_BUSES]; // Under compressor_mutex.
372 static constexpr float ref_level_dbfs = -14.0f; // Chosen so that we end up around 0 LU in practice.
373 static constexpr float ref_level_lufs = -23.0f; // 0 LU, more or less by definition.
375 StereoCompressor limiter;
376 std::atomic<float> limiter_threshold_dbfs{ref_level_dbfs + 4.0f}; // 4 dB.
377 std::atomic<bool> limiter_enabled{true};
378 std::unique_ptr<StereoCompressor> compressor[MAX_BUSES];
379 std::atomic<float> compressor_threshold_dbfs[MAX_BUSES];
380 std::atomic<bool> compressor_enabled[MAX_BUSES];
382 // Note: The values here are not in dB.
384 float current_level = 0.0f; // Peak of the last frame.
385 float historic_peak = 0.0f; // Highest peak since last reset; no falloff.
386 float current_peak = 0.0f; // Current peak of the peak meter.
387 float last_peak = 0.0f;
388 float age_seconds = 0.0f; // Time since "last_peak" was set.
390 PeakHistory peak_history[MAX_BUSES][2]; // Separate for each channel. Under audio_mutex.
392 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.
393 bool final_makeup_gain_auto = true; // Under compressor_mutex.
395 MappingMode current_mapping_mode; // Under audio_mutex.
396 InputMapping input_mapping; // Under audio_mutex.
397 std::atomic<float> fader_volume_db[MAX_BUSES] {{ 0.0f }};
398 std::atomic<bool> mute[MAX_BUSES] {{ false }};
399 float last_fader_volume_db[MAX_BUSES] { 0.0f }; // Under audio_mutex.
400 std::atomic<float> stereo_width[MAX_BUSES] {{ 0.0f }}; // Default 1.0f (is set in constructor).
401 std::atomic<float> eq_level_db[MAX_BUSES][NUM_EQ_BANDS] {{{ 0.0f }}};
402 float last_eq_level_db[MAX_BUSES][NUM_EQ_BANDS] {{ 0.0f }};
404 audio_level_callback_t audio_level_callback = nullptr;
405 state_changed_callback_t state_changed_callback = nullptr;
406 mutable std::mutex audio_measure_mutex;
407 Ebu_r128_proc r128; // Under audio_measure_mutex.
408 CorrelationMeasurer correlation; // Under audio_measure_mutex.
409 Resampler peak_resampler; // Under audio_measure_mutex.
410 std::atomic<float> peak{0.0f};
413 std::atomic<double> metric_audio_loudness_short_lufs{0.0 / 0.0};
414 std::atomic<double> metric_audio_loudness_integrated_lufs{0.0 / 0.0};
415 std::atomic<double> metric_audio_loudness_range_low_lufs{0.0 / 0.0};
416 std::atomic<double> metric_audio_loudness_range_high_lufs{0.0 / 0.0};
417 std::atomic<double> metric_audio_peak_dbfs{0.0 / 0.0};
418 std::atomic<double> metric_audio_final_makeup_gain_db{0.0};
419 std::atomic<double> metric_audio_correlation{0.0};
421 // These are all gauges corresponding to the elements of BusLevel.
422 // In a sense, they'd probably do better as histograms, but that's an
423 // awful lot of time series when you have many buses.
425 std::vector<std::pair<std::string, std::string>> labels;
426 std::atomic<double> current_level_dbfs[2]{{0.0/0.0},{0.0/0.0}};
427 std::atomic<double> peak_level_dbfs[2]{{0.0/0.0},{0.0/0.0}};
428 std::atomic<double> historic_peak_dbfs{0.0/0.0};
429 std::atomic<double> gain_staging_db{0.0/0.0};
430 std::atomic<double> compressor_attenuation_db{0.0/0.0};
432 std::unique_ptr<BusMetrics[]> bus_metrics; // One for each bus in <input_mapping>.
435 extern AudioMixer *global_audio_mixer;
437 #endif // !defined(_AUDIO_MIXER_H)