ref: b05aa1dd763fe238c6e928385664e86bd66118e7
dir: /silk/encode_pulses.c/
/***********************************************************************
Copyright (c) 2006-2011, Skype Limited. All rights reserved.
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modification, are permitted provided that the following conditions
are met:
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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
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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.h"
/*********************************************/
/* Encode quantization indices of excitation */
/*********************************************/
static inline opus_int combine_and_check( /* return ok */
opus_int *pulses_comb, /* O */
const opus_int *pulses_in, /* I */
opus_int max_pulses, /* I max value for sum of pulses */
opus_int len /* I number of output values */
)
{
opus_int k, sum;
for( k = 0; k < len; k++ ) {
sum = pulses_in[ 2 * k ] + pulses_in[ 2 * k + 1 ];
if( sum > max_pulses ) {
return 1;
}
pulses_comb[ k ] = sum;
}
return 0;
}
/* Encode quantization indices of excitation */
void silk_encode_pulses(
ec_enc *psRangeEnc, /* I/O compressor data structure */
const opus_int signalType, /* I Signal type */
const opus_int quantOffsetType, /* I quantOffsetType */
opus_int8 pulses[], /* I quantization indices */
const opus_int frame_length /* I Frame length */
)
{
opus_int i, k, j, iter, bit, nLS, scale_down, RateLevelIndex = 0;
opus_int32 abs_q, minSumBits_Q5, sumBits_Q5;
opus_int abs_pulses[ MAX_FRAME_LENGTH ];
opus_int sum_pulses[ MAX_NB_SHELL_BLOCKS ];
opus_int nRshifts[ MAX_NB_SHELL_BLOCKS ];
opus_int pulses_comb[ 8 ];
opus_int *abs_pulses_ptr;
const opus_int8 *pulses_ptr;
const opus_uint8 *cdf_ptr;
const opus_uint8 *nBits_ptr;
silk_memset( pulses_comb, 0, 8 * sizeof( opus_int ) ); /* Fixing Valgrind reported problem*/
/****************************/
/* Prepare for shell coding */
/****************************/
/* Calculate number of shell blocks */
silk_assert( 1 << LOG2_SHELL_CODEC_FRAME_LENGTH == SHELL_CODEC_FRAME_LENGTH );
iter = silk_RSHIFT( frame_length, LOG2_SHELL_CODEC_FRAME_LENGTH );
if( iter * SHELL_CODEC_FRAME_LENGTH < frame_length ) {
silk_assert( frame_length == 12 * 10 ); /* Make sure only happens for 10 ms @ 12 kHz */
iter++;
silk_memset( &pulses[ frame_length ], 0, SHELL_CODEC_FRAME_LENGTH * sizeof(opus_int8));
}
/* Take the absolute value of the pulses */
for( i = 0; i < iter * SHELL_CODEC_FRAME_LENGTH; i+=4 ) {
abs_pulses[i+0] = ( opus_int )silk_abs( pulses[ i + 0 ] );
abs_pulses[i+1] = ( opus_int )silk_abs( pulses[ i + 1 ] );
abs_pulses[i+2] = ( opus_int )silk_abs( pulses[ i + 2 ] );
abs_pulses[i+3] = ( opus_int )silk_abs( pulses[ i + 3 ] );
}
/* Calc sum pulses per shell code frame */
abs_pulses_ptr = abs_pulses;
for( i = 0; i < iter; i++ ) {
nRshifts[ i ] = 0;
while( 1 ) {
/* 1+1 -> 2 */
scale_down = combine_and_check( pulses_comb, abs_pulses_ptr, silk_max_pulses_table[ 0 ], 8 );
/* 2+2 -> 4 */
scale_down += combine_and_check( pulses_comb, pulses_comb, silk_max_pulses_table[ 1 ], 4 );
/* 4+4 -> 8 */
scale_down += combine_and_check( pulses_comb, pulses_comb, silk_max_pulses_table[ 2 ], 2 );
/* 8+8 -> 16 */
scale_down += combine_and_check( &sum_pulses[ i ], pulses_comb, silk_max_pulses_table[ 3 ], 1 );
if( scale_down ) {
/* We need to downscale the quantization signal */
nRshifts[ i ]++;
for( k = 0; k < SHELL_CODEC_FRAME_LENGTH; k++ ) {
abs_pulses_ptr[ k ] = silk_RSHIFT( abs_pulses_ptr[ k ], 1 );
}
} else {
/* Jump out of while(1) loop and go to next shell coding frame */
break;
}
}
abs_pulses_ptr += SHELL_CODEC_FRAME_LENGTH;
}
/**************/
/* Rate level */
/**************/
/* find rate level that leads to fewest bits for coding of pulses per block info */
minSumBits_Q5 = silk_int32_MAX;
for( k = 0; k < N_RATE_LEVELS - 1; k++ ) {
nBits_ptr = silk_pulses_per_block_BITS_Q5[ k ];
sumBits_Q5 = silk_rate_levels_BITS_Q5[ signalType >> 1 ][ k ];
for( i = 0; i < iter; i++ ) {
if( nRshifts[ i ] > 0 ) {
sumBits_Q5 += nBits_ptr[ MAX_PULSES + 1 ];
} else {
sumBits_Q5 += nBits_ptr[ sum_pulses[ i ] ];
}
}
if( sumBits_Q5 < minSumBits_Q5 ) {
minSumBits_Q5 = sumBits_Q5;
RateLevelIndex = k;
}
}
ec_enc_icdf( psRangeEnc, RateLevelIndex, silk_rate_levels_iCDF[ signalType >> 1 ], 8 );
/***************************************************/
/* Sum-Weighted-Pulses Encoding */
/***************************************************/
cdf_ptr = silk_pulses_per_block_iCDF[ RateLevelIndex ];
for( i = 0; i < iter; i++ ) {
if( nRshifts[ i ] == 0 ) {
ec_enc_icdf( psRangeEnc, sum_pulses[ i ], cdf_ptr, 8 );
} else {
ec_enc_icdf( psRangeEnc, MAX_PULSES + 1, cdf_ptr, 8 );
for( k = 0; k < nRshifts[ i ] - 1; k++ ) {
ec_enc_icdf( psRangeEnc, MAX_PULSES + 1, silk_pulses_per_block_iCDF[ N_RATE_LEVELS - 1 ], 8 );
}
ec_enc_icdf( psRangeEnc, sum_pulses[ i ], silk_pulses_per_block_iCDF[ N_RATE_LEVELS - 1 ], 8 );
}
}
/******************/
/* Shell Encoding */
/******************/
for( i = 0; i < iter; i++ ) {
if( sum_pulses[ i ] > 0 ) {
silk_shell_encoder( psRangeEnc, &abs_pulses[ i * SHELL_CODEC_FRAME_LENGTH ] );
}
}
/****************/
/* LSB Encoding */
/****************/
for( i = 0; i < iter; i++ ) {
if( nRshifts[ i ] > 0 ) {
pulses_ptr = &pulses[ i * SHELL_CODEC_FRAME_LENGTH ];
nLS = nRshifts[ i ] - 1;
for( k = 0; k < SHELL_CODEC_FRAME_LENGTH; k++ ) {
abs_q = (opus_int8)silk_abs( pulses_ptr[ k ] );
for( j = nLS; j > 0; j-- ) {
bit = silk_RSHIFT( abs_q, j ) & 1;
ec_enc_icdf( psRangeEnc, bit, silk_lsb_iCDF, 8 );
}
bit = abs_q & 1;
ec_enc_icdf( psRangeEnc, bit, silk_lsb_iCDF, 8 );
}
}
}
/****************/
/* Encode signs */
/****************/
silk_encode_signs( psRangeEnc, pulses, frame_length, signalType, quantOffsetType, sum_pulses );
}