зеркало из https://github.com/mozilla/gecko-dev.git
74 строки
3.5 KiB
C
74 строки
3.5 KiB
C
/***********************************************************************
|
|
Copyright (c) 2006-2011, Skype Limited. All rights reserved.
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
- Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions and the following disclaimer.
|
|
- Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
- Neither the name of Internet Society, IETF or IETF Trust, nor the
|
|
names of specific contributors, may be used to endorse or promote
|
|
products derived from this software without specific prior written
|
|
permission.
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
***********************************************************************/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include "main_FLP.h"
|
|
|
|
/* Autocorrelations for a warped frequency axis */
|
|
void silk_warped_autocorrelation_FLP(
|
|
silk_float *corr, /* O Result [order + 1] */
|
|
const silk_float *input, /* I Input data to correlate */
|
|
const silk_float warping, /* I Warping coefficient */
|
|
const opus_int length, /* I Length of input */
|
|
const opus_int order /* I Correlation order (even) */
|
|
)
|
|
{
|
|
opus_int n, i;
|
|
double tmp1, tmp2;
|
|
double state[ MAX_SHAPE_LPC_ORDER + 1 ] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 };
|
|
double C[ MAX_SHAPE_LPC_ORDER + 1 ] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 };
|
|
|
|
/* Order must be even */
|
|
silk_assert( ( order & 1 ) == 0 );
|
|
|
|
/* Loop over samples */
|
|
for( n = 0; n < length; n++ ) {
|
|
tmp1 = input[ n ];
|
|
/* Loop over allpass sections */
|
|
for( i = 0; i < order; i += 2 ) {
|
|
/* Output of allpass section */
|
|
tmp2 = state[ i ] + warping * ( state[ i + 1 ] - tmp1 );
|
|
state[ i ] = tmp1;
|
|
C[ i ] += state[ 0 ] * tmp1;
|
|
/* Output of allpass section */
|
|
tmp1 = state[ i + 1 ] + warping * ( state[ i + 2 ] - tmp2 );
|
|
state[ i + 1 ] = tmp2;
|
|
C[ i + 1 ] += state[ 0 ] * tmp2;
|
|
}
|
|
state[ order ] = tmp1;
|
|
C[ order ] += state[ 0 ] * tmp1;
|
|
}
|
|
|
|
/* Copy correlations in silk_float output format */
|
|
for( i = 0; i < order + 1; i++ ) {
|
|
corr[ i ] = ( silk_float )C[ i ];
|
|
}
|
|
}
|