}
}
- // TODO: We should measure post-fader.
- deinterleave_samples(samples_bus, &left, &right);
- measure_bus_levels(bus_index, left, right);
-
float volume = from_db(fader_volume_db[bus_index]);
if (bus_index == 0) {
for (unsigned i = 0; i < num_samples * 2; ++i) {
samples_out[i] += samples_bus[i] * volume;
}
}
+
+ deinterleave_samples(samples_bus, &left, &right);
+ measure_bus_levels(bus_index, left, right, volume);
}
{
return samples_out;
}
-void AudioMixer::measure_bus_levels(unsigned bus_index, const vector<float> &left, const vector<float> &right)
+void AudioMixer::measure_bus_levels(unsigned bus_index, const vector<float> &left, const vector<float> &right, float volume)
{
- const float *ptrs[] = { left.data(), right.data() };
- {
- lock_guard<mutex> lock(audio_measure_mutex);
- bus_r128[bus_index]->process(left.size(), const_cast<float **>(ptrs));
+ assert(left.size() == right.size());
+ const float peak_levels[2] = {
+ find_peak(left.data(), left.size()) * volume,
+ find_peak(right.data(), right.size()) * volume
+ };
+ for (unsigned channel = 0; channel < 2; ++channel) {
+ // Compute the current value, including hold and falloff.
+ // The constants are borrowed from zita-mu1 by Fons Adriaensen.
+ static constexpr float hold_sec = 0.5f;
+ static constexpr float falloff_db_sec = 15.0f; // dB/sec falloff after hold.
+ float current_peak;
+ PeakHistory &history = peak_history[bus_index][channel];
+ if (history.age_seconds < hold_sec) {
+ current_peak = history.last_peak;
+ } else {
+ current_peak = history.last_peak * from_db(-falloff_db_sec * (history.age_seconds - hold_sec));
+ }
+
+ // See if we have a new peak to replace the old (possibly falling) one.
+ if (peak_levels[channel] > current_peak) {
+ history.last_peak = peak_levels[channel];
+ history.age_seconds = 0.0f; // Not 100% correct, but more than good enough given our frame sizes.
+ current_peak = peak_levels[channel];
+ } else {
+ history.age_seconds += float(left.size()) / OUTPUT_FREQUENCY;
+ }
+ history.current_level = peak_levels[channel];
+ history.current_peak = current_peak;
}
}
bus_levels.resize(input_mapping.buses.size());
{
lock_guard<mutex> lock(compressor_mutex);
- for (unsigned bus_index = 0; bus_index < bus_r128.size(); ++bus_index) {
- bus_levels[bus_index].loudness_lufs = bus_r128[bus_index]->loudness_S();
+ for (unsigned bus_index = 0; bus_index < bus_levels.size(); ++bus_index) {
+ bus_levels[bus_index].current_level_dbfs[0] = to_db(peak_history[bus_index][0].current_level);
+ bus_levels[bus_index].current_level_dbfs[1] = to_db(peak_history[bus_index][1].current_level);
+ bus_levels[bus_index].peak_level_dbfs[0] = to_db(peak_history[bus_index][0].current_peak);
+ bus_levels[bus_index].peak_level_dbfs[1] = to_db(peak_history[bus_index][1].current_peak);
bus_levels[bus_index].gain_staging_db = gain_staging_db[bus_index];
if (compressor_enabled[bus_index]) {
bus_levels[bus_index].compressor_attenuation_db = -to_db(compressor[bus_index]->get_attenuation());
}
}
- {
- lock_guard<mutex> lock(audio_measure_mutex);
- bus_r128.resize(new_input_mapping.buses.size());
- for (unsigned bus_index = 0; bus_index < bus_r128.size(); ++bus_index) {
- if (bus_r128[bus_index] == nullptr) {
- bus_r128[bus_index].reset(new Ebu_r128_proc);
- }
- bus_r128[bus_index]->init(2, OUTPUT_FREQUENCY);
- }
- }
-
input_mapping = new_input_mapping;
}