]> git.sesse.net Git - nageru/blobdiff - audio_mixer.cpp
Implement auto-training controllers in the MIDI input mapping dialog.
[nageru] / audio_mixer.cpp
index 197b4f34605a1b27818c4fb45a40fd715387a83b..e4eb495953baaa49cd487f2b5e16960857d88efb 100644 (file)
@@ -6,6 +6,7 @@
 #include <stdio.h>
 #include <endian.h>
 #include <cmath>
+#include <limits>
 #ifdef __SSE__
 #include <immintrin.h>
 #endif
@@ -179,8 +180,9 @@ AudioMixer::AudioMixer(unsigned num_cards)
        set_final_makeup_gain_auto(global_flags.final_makeup_gain_auto);
        alsa_pool.init();
 
-       InputMapping new_input_mapping;
        if (!global_flags.input_mapping_filename.empty()) {
+               current_mapping_mode = MappingMode::MULTICHANNEL;
+               InputMapping new_input_mapping;
                if (!load_input_mapping_from_file(get_devices(),
                                                  global_flags.input_mapping_filename,
                                                  &new_input_mapping)) {
@@ -188,18 +190,13 @@ AudioMixer::AudioMixer(unsigned num_cards)
                                global_flags.input_mapping_filename.c_str());
                        exit(1);
                }
+               set_input_mapping(new_input_mapping);
        } else {
-               // Generate a very simple, default input mapping.
-               InputMapping::Bus input;
-               input.name = "Main";
-               input.device.type = InputSourceType::CAPTURE_CARD;
-               input.device.index = 0;
-               input.source_channel[0] = 0;
-               input.source_channel[1] = 1;
-
-               new_input_mapping.buses.push_back(input);
+               set_simple_input(/*card_index=*/0);
+               if (global_flags.multichannel_mapping_mode) {
+                       current_mapping_mode = MappingMode::MULTICHANNEL;
+               }
        }
-       set_input_mapping(new_input_mapping);
 
        r128.init(2, OUTPUT_FREQUENCY);
        r128.integr_start();
@@ -358,6 +355,7 @@ void AudioMixer::set_bus_settings(unsigned bus_index, const AudioMixer::BusSetti
                eq_level_db[bus_index][band_index] = settings.eq_level_db[band_index];
        }
        gain_staging_db[bus_index] = settings.gain_staging_db;
+       last_gain_staging_db[bus_index] = gain_staging_db[bus_index];
        level_compressor_enabled[bus_index] = settings.level_compressor_enabled;
        compressor_threshold_dbfs[bus_index] = settings.compressor_threshold_dbfs;
        compressor_enabled[bus_index] = settings.compressor_enabled;
@@ -441,6 +439,31 @@ vector<DeviceSpec> AudioMixer::get_active_devices() const
        return ret;
 }
 
+namespace {
+
+void apply_gain(float db, float last_db, vector<float> *samples)
+{
+       if (fabs(db - last_db) < 1e-3) {
+               // Constant over this frame.
+               const float gain = from_db(db);
+               for (size_t i = 0; i < samples->size(); ++i) {
+                       (*samples)[i] *= gain;
+               }
+       } else {
+               // We need to do a fade.
+               unsigned num_samples = samples->size() / 2;
+               float gain = from_db(last_db);
+               const float gain_inc = pow(from_db(db - last_db), 1.0 / num_samples);
+               for (size_t i = 0; i < num_samples; ++i) {
+                       (*samples)[i * 2 + 0] *= gain;
+                       (*samples)[i * 2 + 1] *= gain;
+                       gain *= gain_inc;
+               }
+       }
+}
+
+}  // namespace
+
 vector<float> AudioMixer::get_output(double pts, unsigned num_samples, ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy)
 {
        map<DeviceSpec, vector<float>> samples_card;
@@ -489,11 +512,11 @@ vector<float> AudioMixer::get_output(double pts, unsigned num_samples, Resamplin
                                gain_staging_db[bus_index] = to_db(level_compressor[bus_index]->get_attenuation() * makeup_gain);
                        } else {
                                // Just apply the gain we already had.
-                               float g = from_db(gain_staging_db[bus_index]);
-                               for (size_t i = 0; i < samples_bus.size(); ++i) {
-                                       samples_bus[i] *= g;
-                               }
+                               float db = gain_staging_db[bus_index];
+                               float last_db = last_gain_staging_db[bus_index];
+                               apply_gain(db, last_db, &samples_bus);
                        }
+                       last_gain_staging_db[bus_index] = gain_staging_db[bus_index];
 
 #if 0
                        printf("level=%f (%+5.2f dBFS) attenuation=%f (%+5.2f dB) end_result=%+5.2f dB\n",
@@ -583,6 +606,36 @@ vector<float> AudioMixer::get_output(double pts, unsigned num_samples, Resamplin
        return samples_out;
 }
 
+namespace {
+
+void apply_filter_fade(StereoFilter *filter, float *data, unsigned num_samples, float cutoff_hz, float db, float last_db)
+{
+       // A granularity of 32 samples is an okay tradeoff between speed and
+       // smoothness; recalculating the filters is pretty expensive, so it's
+       // good that we don't do this all the time.
+       static constexpr unsigned filter_granularity_samples = 32;
+
+       const float cutoff_linear = cutoff_hz * 2.0 * M_PI / OUTPUT_FREQUENCY;
+       if (fabs(db - last_db) < 1e-3) {
+               // Constant over this frame.
+               if (fabs(db) > 0.01f) {
+                       filter->render(data, num_samples, cutoff_linear, 0.5f, db / 40.0f);
+               }
+       } else {
+               // We need to do a fade. (Rounding up avoids division by zero.)
+               unsigned num_blocks = (num_samples + filter_granularity_samples - 1) / filter_granularity_samples;
+               const float inc_db_norm = (db - last_db) / 40.0f / num_blocks;
+               float db_norm = db / 40.0f;
+               for (size_t i = 0; i < num_samples; i += filter_granularity_samples) {
+                       size_t samples_this_block = std::min<size_t>(num_samples - i, filter_granularity_samples);
+                       filter->render(data + i * 2, samples_this_block, cutoff_linear, 0.5f, db_norm);
+                       db_norm += inc_db_norm;
+               }
+       }
+}
+
+}  // namespace
+
 void AudioMixer::apply_eq(unsigned bus_index, vector<float> *samples_bus)
 {
        constexpr float bass_freq_hz = 200.0f;
@@ -601,24 +654,28 @@ void AudioMixer::apply_eq(unsigned bus_index, vector<float> *samples_bus)
        // set the mid-level filter, and then offset the low and high bands
        // from that if we need to. (We could perhaps have folded the gain into
        // the next part, but it's so cheap that the trouble isn't worth it.)
-       if (fabs(eq_level_db[bus_index][EQ_BAND_MID]) > 0.01f) {
-               float g = from_db(eq_level_db[bus_index][EQ_BAND_MID]);
-               for (size_t i = 0; i < samples_bus->size(); ++i) {
-                       (*samples_bus)[i] *= g;
-               }
-       }
+       //
+       // If any part of the EQ has changed appreciably since last frame,
+       // we fade smoothly during the course of this frame.
+       const float bass_db = eq_level_db[bus_index][EQ_BAND_BASS];
+       const float mid_db = eq_level_db[bus_index][EQ_BAND_MID];
+       const float treble_db = eq_level_db[bus_index][EQ_BAND_TREBLE];
 
-       float bass_adj_db = eq_level_db[bus_index][EQ_BAND_BASS] - eq_level_db[bus_index][EQ_BAND_MID];
-       if (fabs(bass_adj_db) > 0.01f) {
-               eq[bus_index][EQ_BAND_BASS].render(samples_bus->data(), samples_bus->size() / 2,
-                       bass_freq_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f, bass_adj_db / 40.0f);
-       }
+       const float last_bass_db = last_eq_level_db[bus_index][EQ_BAND_BASS];
+       const float last_mid_db = last_eq_level_db[bus_index][EQ_BAND_MID];
+       const float last_treble_db = last_eq_level_db[bus_index][EQ_BAND_TREBLE];
 
-       float treble_adj_db = eq_level_db[bus_index][EQ_BAND_TREBLE] - eq_level_db[bus_index][EQ_BAND_MID];
-       if (fabs(treble_adj_db) > 0.01f) {
-               eq[bus_index][EQ_BAND_TREBLE].render(samples_bus->data(), samples_bus->size() / 2,
-                       treble_freq_hz * 2.0 * M_PI / OUTPUT_FREQUENCY, 0.5f, treble_adj_db / 40.0f);
-       }
+       assert(samples_bus->size() % 2 == 0);
+       const unsigned num_samples = samples_bus->size() / 2;
+
+       apply_gain(mid_db, last_mid_db, samples_bus);
+
+       apply_filter_fade(&eq[bus_index][EQ_BAND_BASS], samples_bus->data(), num_samples, bass_freq_hz, bass_db - mid_db, last_bass_db - last_mid_db);
+       apply_filter_fade(&eq[bus_index][EQ_BAND_TREBLE], samples_bus->data(), num_samples, treble_freq_hz, treble_db - mid_db, last_treble_db - last_mid_db);
+
+       last_eq_level_db[bus_index][EQ_BAND_BASS] = bass_db;
+       last_eq_level_db[bus_index][EQ_BAND_MID] = mid_db;
+       last_eq_level_db[bus_index][EQ_BAND_TREBLE] = treble_db;
 }
 
 void AudioMixer::add_bus_to_master(unsigned bus_index, const vector<float> &samples_bus, vector<float> *samples_out)
@@ -839,10 +896,52 @@ void AudioMixer::serialize_device(DeviceSpec device_spec, DeviceSpecProto *devic
        }
 }
 
+void AudioMixer::set_simple_input(unsigned card_index)
+{
+       InputMapping new_input_mapping;
+       InputMapping::Bus input;
+       input.name = "Main";
+       input.device.type = InputSourceType::CAPTURE_CARD;
+       input.device.index = card_index;
+       input.source_channel[0] = 0;
+       input.source_channel[1] = 1;
+
+       new_input_mapping.buses.push_back(input);
+
+       lock_guard<timed_mutex> lock(audio_mutex);
+       current_mapping_mode = MappingMode::SIMPLE;
+       set_input_mapping_lock_held(new_input_mapping);
+       fader_volume_db[0] = 0.0f;
+}
+
+unsigned AudioMixer::get_simple_input() const
+{
+       lock_guard<timed_mutex> lock(audio_mutex);
+       if (input_mapping.buses.size() == 1 &&
+           input_mapping.buses[0].device.type == InputSourceType::CAPTURE_CARD &&
+           input_mapping.buses[0].source_channel[0] == 0 &&
+           input_mapping.buses[0].source_channel[1] == 1) {
+               return input_mapping.buses[0].device.index;
+       } else {
+               return numeric_limits<unsigned>::max();
+       }
+}
+
 void AudioMixer::set_input_mapping(const InputMapping &new_input_mapping)
 {
        lock_guard<timed_mutex> lock(audio_mutex);
+       set_input_mapping_lock_held(new_input_mapping);
+       current_mapping_mode = MappingMode::MULTICHANNEL;
+}
+
+AudioMixer::MappingMode AudioMixer::get_mapping_mode() const
+{
+       lock_guard<timed_mutex> lock(audio_mutex);
+       return current_mapping_mode;
+}
 
+void AudioMixer::set_input_mapping_lock_held(const InputMapping &new_input_mapping)
+{
        map<DeviceSpec, set<unsigned>> interesting_channels;
        for (const InputMapping::Bus &bus : new_input_mapping.buses) {
                if (bus.device.type == InputSourceType::CAPTURE_CARD ||