You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
84 lines
3.7 KiB
84 lines
3.7 KiB
/***********************************************************************
|
|
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 "SigProc_FIX.h"
|
|
|
|
/* Compute number of bits to right shift the sum of squares of a vector */
|
|
/* of int16s to make it fit in an int32 */
|
|
void silk_sum_sqr_shift(
|
|
opus_int32 *energy, /* O Energy of x, after shifting to the right */
|
|
opus_int *shift, /* O Number of bits right shift applied to energy */
|
|
const opus_int16 *x, /* I Input vector */
|
|
opus_int len /* I Length of input vector */
|
|
)
|
|
{
|
|
opus_int i, shft;
|
|
opus_uint32 nrg_tmp;
|
|
opus_int32 nrg;
|
|
|
|
/* Do a first run with the maximum shift we could have. */
|
|
shft = 31-silk_CLZ32(len);
|
|
/* Let's be conservative with rounding and start with nrg=len. */
|
|
nrg = len;
|
|
for( i = 0; i < len - 1; i += 2 ) {
|
|
nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
nrg_tmp = silk_SMLABB_ovflw( nrg_tmp, x[ i + 1 ], x[ i + 1 ] );
|
|
nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
}
|
|
if( i < len ) {
|
|
/* One sample left to process */
|
|
nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
}
|
|
silk_assert( nrg >= 0 );
|
|
/* Make sure the result will fit in a 32-bit signed integer with two bits
|
|
of headroom. */
|
|
shft = silk_max_32(0, shft+3 - silk_CLZ32(nrg));
|
|
nrg = 0;
|
|
for( i = 0 ; i < len - 1; i += 2 ) {
|
|
nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
nrg_tmp = silk_SMLABB_ovflw( nrg_tmp, x[ i + 1 ], x[ i + 1 ] );
|
|
nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
}
|
|
if( i < len ) {
|
|
/* One sample left to process */
|
|
nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
}
|
|
|
|
silk_assert( nrg >= 0 );
|
|
|
|
/* Output arguments */
|
|
*shift = shft;
|
|
*energy = nrg;
|
|
}
|
|
|