blob: 6011e921a92889386cbe549990f0eded2b5e180e [file] [log] [blame]
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
iLBC Speech Coder ANSI-C Source Code
#include "defines.h"
#include "constants.h"
#include "augmented_cb_corr.h"
void WebRtcIlbcfix_AugmentedCbCorr(
WebRtc_Word16 *target, /* (i) Target vector */
WebRtc_Word16 *buffer, /* (i) Memory buffer */
WebRtc_Word16 *interpSamples, /* (i) buffer with
interpolated samples */
WebRtc_Word32 *crossDot, /* (o) The cross correlation between
the target and the Augmented
vector */
WebRtc_Word16 low, /* (i) Lag to start from (typically
20) */
WebRtc_Word16 high, /* (i) Lag to end at (typically 39) */
WebRtc_Word16 scale) /* (i) Scale factor to use for
the crossDot */
int lagcount;
WebRtc_Word16 ilow;
WebRtc_Word16 *targetPtr;
WebRtc_Word32 *crossDotPtr;
WebRtc_Word16 *iSPtr=interpSamples;
/* Calculate the correlation between the target and the
interpolated codebook. The correlation is calculated in
3 sections with the interpolated part in the middle */
for (lagcount=low; lagcount<=high; lagcount++) {
ilow = (WebRtc_Word16) (lagcount-4);
/* Compute dot product for the first (lagcount-4) samples */
(*crossDotPtr) = WebRtcSpl_DotProductWithScale(target, buffer-lagcount, ilow, scale);
/* Compute dot product on the interpolated samples */
(*crossDotPtr) += WebRtcSpl_DotProductWithScale(target+ilow, iSPtr, 4, scale);
targetPtr = target + lagcount;
iSPtr += lagcount-ilow;
/* Compute dot product for the remaining samples */
(*crossDotPtr) += WebRtcSpl_DotProductWithScale(targetPtr, buffer-lagcount, SUBL-lagcount, scale);