zqz/platform-external-webrtc
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Reland "Avoiding overflow in cross correlation in NetEq."

Browse Source 
The original CL is https://codereview.webrtc.org/1908623002/

An error was caused by that and this CL fix that problem and reland the CL.

BUG=

Review-Url: https://codereview.webrtc.org/1931933004
Cr-Commit-Position: refs/heads/master@{#12589}
This commit is contained in:
minyue
2016-05-02 01:50:30 -07:00
committed by Commit bot
parent a017b8ed2e
commit 53ff70f582
12 changed files with 186 additions and 105 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
webrtc/modules/audio_coding/neteq/expand.cc
View File

@ -19,6 +19,7 @@
#include "webrtc/base/safe_conversions.h"
#include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
#include "webrtc/modules/audio_coding/neteq/background_noise.h"
#include "webrtc/modules/audio_coding/neteq/cross_correlation.h"
#include "webrtc/modules/audio_coding/neteq/dsp_helper.h"
#include "webrtc/modules/audio_coding/neteq/random_vector.h"
#include "webrtc/modules/audio_coding/neteq/statistics_calculator.h"
@ -379,12 +380,10 @@ void Expand::AnalyzeSignal(int16_t* random_vector) {
InitializeForAnExpandPeriod();
// Calculate correlation in downsampled domain (4 kHz sample rate).
int correlation_scale;
size_t correlation_length = 51; // TODO(hlundin): Legacy bit-exactness.
// If it is decided to break bit-exactness |correlation_length| should be
// initialized to the return value of Correlation().
Correlation(audio_history, signal_length, correlation_vector,
&correlation_scale);
Correlation(audio_history, signal_length, correlation_vector);
// Find peaks in correlation vector.
DspHelper::PeakDetection(correlation_vector, correlation_length,
@ -455,7 +454,7 @@ void Expand::AnalyzeSignal(int16_t* random_vector) {
&audio_history[signal_length - correlation_length - start_index
- correlation_lags],
correlation_length + start_index + correlation_lags - 1);
correlation_scale = (31 - WebRtcSpl_NormW32(signal_max * signal_max)) +
int correlation_scale = (31 - WebRtcSpl_NormW32(signal_max * signal_max)) +
(31 - WebRtcSpl_NormW32(static_cast<int32_t>(correlation_length))) - 31;
correlation_scale = std::max(0, correlation_scale);
@ -582,13 +581,6 @@ void Expand::AnalyzeSignal(int16_t* random_vector) {
}
// Calculate the LPC and the gain of the filters.
// Calculate scale value needed for auto-correlation.
correlation_scale = WebRtcSpl_MaxAbsValueW16(
&(audio_history[signal_length - fs_mult_lpc_analysis_len]),
fs_mult_lpc_analysis_len);
correlation_scale = std::min(16 - WebRtcSpl_NormW32(correlation_scale), 0);
correlation_scale = std::max(correlation_scale * 2 + 7, 0);
// Calculate kUnvoicedLpcOrder + 1 lags of the auto-correlation function.
size_t temp_index = signal_length - fs_mult_lpc_analysis_len -
@ -601,11 +593,9 @@ void Expand::AnalyzeSignal(int16_t* random_vector) {
memcpy(&temp_signal[kUnvoicedLpcOrder],
&audio_history[temp_index + kUnvoicedLpcOrder],
sizeof(int16_t) * fs_mult_lpc_analysis_len);
WebRtcSpl_CrossCorrelation(auto_correlation,
&temp_signal[kUnvoicedLpcOrder],
&temp_signal[kUnvoicedLpcOrder],
fs_mult_lpc_analysis_len, kUnvoicedLpcOrder + 1,
correlation_scale, -1);
CrossCorrelationWithAutoShift(
&temp_signal[kUnvoicedLpcOrder], &temp_signal[kUnvoicedLpcOrder],
fs_mult_lpc_analysis_len, kUnvoicedLpcOrder + 1, -1, auto_correlation);
delete [] temp_signal;
// Verify that variance is positive.
@ -766,8 +756,7 @@ Expand::ChannelParameters::ChannelParameters()
void Expand::Correlation(const int16_t* input,
size_t input_length,
int16_t* output,
int* output_scale) const {
int16_t* output) const {
// Set parameters depending on sample rate.
const int16_t* filter_coefficients;
size_t num_coefficients;
@ -814,13 +803,11 @@ void Expand::Correlation(const int16_t* input,
downsampled_input, norm_shift);
int32_t correlation[kNumCorrelationLags];
static const int kCorrelationShift = 6;
WebRtcSpl_CrossCorrelation(
correlation,
CrossCorrelationWithAutoShift(
&downsampled_input[kDownsampledLength - kCorrelationLength],
&downsampled_input[kDownsampledLength - kCorrelationLength
- kCorrelationStartLag],
kCorrelationLength, kNumCorrelationLags, kCorrelationShift, -1);
kCorrelationLength, kNumCorrelationLags, -1, correlation);
// Normalize and move data from 32-bit to 16-bit vector.
int32_t max_correlation = WebRtcSpl_MaxAbsValueW32(correlation,
@ -829,8 +816,6 @@ void Expand::Correlation(const int16_t* input,
std::max(18 - WebRtcSpl_NormW32(max_correlation), 0));
WebRtcSpl_VectorBitShiftW32ToW16(output, kNumCorrelationLags, correlation,
norm_shift2);
// Total scale factor (right shifts) of correlation value.
*output_scale = 2 * norm_shift + kCorrelationShift + norm_shift2;
}
void Expand::UpdateLagIndex() {