NetEq: Remove background noise fill during long expansions
NetEq was (up until this CL) capable of fading over to generating a
constant background noise when voice expansion had lasted too long.
However, the code has for a really long time only ever used the "off"
mode, which meant that long expansions are faded down to complete
silence (only zeros), i.e., background noise fill was not used.
Removing the other two modes ("on" and "fade") simplifies the code.
Bug: webrtc:9180
Change-Id: Ia2d46960208f3d75c9659ad3f027c52e5ecfb6b0
Reviewed-on: https://webrtc-review.googlesource.com/71485
Commit-Queue: Henrik Lundin <henrik.lundin@webrtc.org>
Reviewed-by: Minyue Li <minyue@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22969}diff --git a/modules/audio_coding/neteq/expand.cc b/modules/audio_coding/neteq/expand.cc
index 3fb09ea..03bcc77 100644
--- a/modules/audio_coding/neteq/expand.cc
+++ b/modules/audio_coding/neteq/expand.cc
@@ -911,46 +911,10 @@
// Unmute the background noise.
int16_t bgn_mute_factor = background_noise_->MuteFactor(channel);
- NetEq::BackgroundNoiseMode bgn_mode = background_noise_->mode();
- if (bgn_mode == NetEq::kBgnFade && too_many_expands &&
- bgn_mute_factor > 0) {
- // Fade BGN to zero.
- // Calculate muting slope, approximately -2^18 / fs_hz.
- int mute_slope;
- if (fs_hz_ == 8000) {
- mute_slope = -32;
- } else if (fs_hz_ == 16000) {
- mute_slope = -16;
- } else if (fs_hz_ == 32000) {
- mute_slope = -8;
- } else {
- mute_slope = -5;
- }
- // Use UnmuteSignal function with negative slope.
- // |bgn_mute_factor| is in Q14. |mute_slope| is in Q20.
- DspHelper::UnmuteSignal(noise_samples,
- num_noise_samples,
- &bgn_mute_factor,
- mute_slope,
- noise_samples);
- } else if (bgn_mute_factor < 16384) {
- // If mode is kBgnOn, or if kBgnFade has started fading,
- // use regular |mute_slope|.
- if (!stop_muting_ && bgn_mode != NetEq::kBgnOff &&
- !(bgn_mode == NetEq::kBgnFade && too_many_expands)) {
- DspHelper::UnmuteSignal(noise_samples,
- static_cast<int>(num_noise_samples),
- &bgn_mute_factor,
- mute_slope,
- noise_samples);
- } else {
- // kBgnOn and stop muting, or
- // kBgnOff (mute factor is always 0), or
- // kBgnFade has reached 0.
- WebRtcSpl_AffineTransformVector(noise_samples, noise_samples,
- bgn_mute_factor, 8192, 14,
- num_noise_samples);
- }
+ if (bgn_mute_factor < 16384) {
+ WebRtcSpl_AffineTransformVector(noise_samples, noise_samples,
+ bgn_mute_factor, 8192, 14,
+ num_noise_samples);
}
// Update mute_factor in BackgroundNoise class.
background_noise_->SetMuteFactor(channel, bgn_mute_factor);