NetEQ: BackgroundNoise::Update returns true when the filter is updated
Bug: webrtc:10690
Change-Id: I17ff7dc1cffc8c46987d0a9ff8c6633ce9dcc8d3
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/144040
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Reviewed-by: Henrik Lundin <henrik.lundin@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28411}
diff --git a/modules/audio_coding/neteq/background_noise.cc b/modules/audio_coding/neteq/background_noise.cc
index 5bb9d7e..c0dcc5e 100644
--- a/modules/audio_coding/neteq/background_noise.cc
+++ b/modules/audio_coding/neteq/background_noise.cc
@@ -45,12 +45,13 @@
}
}
-void BackgroundNoise::Update(const AudioMultiVector& input,
+bool BackgroundNoise::Update(const AudioMultiVector& input,
const PostDecodeVad& vad) {
+ bool filter_params_saved = false;
if (vad.running() && vad.active_speech()) {
// Do not update the background noise parameters if we know that the signal
// is active speech.
- return;
+ return filter_params_saved;
}
int32_t auto_correlation[kMaxLpcOrder + 1];
@@ -62,6 +63,7 @@
ChannelParameters& parameters = channel_parameters_[channel_ix];
int16_t temp_signal_array[kVecLen + kMaxLpcOrder] = {0};
int16_t* temp_signal = &temp_signal_array[kMaxLpcOrder];
+ RTC_DCHECK_GE(input.Size(), kVecLen);
input[channel_ix].CopyTo(kVecLen, input.Size() - kVecLen, temp_signal);
int32_t sample_energy =
CalculateAutoCorrelation(temp_signal, kVecLen, auto_correlation);
@@ -70,26 +72,26 @@
sample_energy < parameters.energy_update_threshold) ||
(vad.running() && !vad.active_speech())) {
// Generate LPC coefficients.
- if (auto_correlation[0] > 0) {
- // Regardless of whether the filter is actually updated or not,
- // update energy threshold levels, since we have in fact observed
- // a low energy signal.
- if (sample_energy < parameters.energy_update_threshold) {
- // Never go under 1.0 in average sample energy.
- parameters.energy_update_threshold = std::max(sample_energy, 1);
- parameters.low_energy_update_threshold = 0;
- }
-
- // Only update BGN if filter is stable, i.e., if return value from
- // Levinson-Durbin function is 1.
- if (WebRtcSpl_LevinsonDurbin(auto_correlation, lpc_coefficients,
- reflection_coefficients,
- kMaxLpcOrder) != 1) {
- return;
- }
- } else {
+ if (auto_correlation[0] <= 0) {
// Center value in auto-correlation is not positive. Do not update.
- return;
+ return filter_params_saved;
+ }
+
+ // Regardless of whether the filter is actually updated or not,
+ // update energy threshold levels, since we have in fact observed
+ // a low energy signal.
+ if (sample_energy < parameters.energy_update_threshold) {
+ // Never go under 1.0 in average sample energy.
+ parameters.energy_update_threshold = std::max(sample_energy, 1);
+ parameters.low_energy_update_threshold = 0;
+ }
+
+ // Only update BGN if filter is stable, i.e., if return value from
+ // Levinson-Durbin function is 1.
+ if (WebRtcSpl_LevinsonDurbin(auto_correlation, lpc_coefficients,
+ reflection_coefficients,
+ kMaxLpcOrder) != 1) {
+ return filter_params_saved;
}
// Generate the CNG gain factor by looking at the energy of the residual.
@@ -113,6 +115,7 @@
SaveParameters(channel_ix, lpc_coefficients,
temp_signal + kVecLen - kMaxLpcOrder, sample_energy,
residual_energy);
+ filter_params_saved = true;
}
} else {
// Will only happen if post-decode VAD is disabled and |sample_energy| is
@@ -121,7 +124,7 @@
IncrementEnergyThreshold(channel_ix, sample_energy);
}
}
- return;
+ return filter_params_saved;
}
void BackgroundNoise::GenerateBackgroundNoise(
diff --git a/modules/audio_coding/neteq/background_noise.h b/modules/audio_coding/neteq/background_noise.h
index 0286320..5191179 100644
--- a/modules/audio_coding/neteq/background_noise.h
+++ b/modules/audio_coding/neteq/background_noise.h
@@ -37,7 +37,8 @@
// Updates the parameter estimates based on the signal currently in the
// |sync_buffer|, and on the latest decision in |vad| if it is running.
- void Update(const AudioMultiVector& sync_buffer, const PostDecodeVad& vad);
+ // Returns true if the filter parameters are updated.
+ bool Update(const AudioMultiVector& sync_buffer, const PostDecodeVad& vad);
// Generates background noise given a random vector and writes the output to
// |buffer|.
