media/libopus/silk/encode_pulses.c

   1 /***********************************************************************
   2 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
   3 Redistribution and use in source and binary forms, with or without
   4 modification, are permitted provided that the following conditions
   5 are met:
   6 - Redistributions of source code must retain the above copyright notice,
   7 this list of conditions and the following disclaimer.
   8 - Redistributions in binary form must reproduce the above copyright
   9 notice, this list of conditions and the following disclaimer in the
  10 documentation and/or other materials provided with the distribution.
  11 - Neither the name of Internet Society, IETF or IETF Trust, nor the
  12 names of specific contributors, may be used to endorse or promote
  13 products derived from this software without specific prior written
  14 permission.
  15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  16 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  19 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  20 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  21 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  22 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  24 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  25 POSSIBILITY OF SUCH DAMAGE.
  26 ***********************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 #include "config.h"
  30 #endif
  31
  32 #include "main.h"
  33 #include "stack_alloc.h"
  34
  35 /*********************************************/
  36 /* Encode quantization indices of excitation */
  37 /*********************************************/
  38
  39 static OPUS_INLINE opus_int combine_and_check(    /* return ok                           */
  40     opus_int         *pulses_comb,           /* O                                   */
  41     const opus_int   *pulses_in,             /* I                                   */
  42     opus_int         max_pulses,             /* I    max value for sum of pulses    */
  43     opus_int         len                     /* I    number of output values        */
  44 )
  45 {
  46     opus_int k, sum;
  47
  48     for( k = 0; k < len; k++ ) {
  49         sum = pulses_in[ 2 * k ] + pulses_in[ 2 * k + 1 ];
  50         if( sum > max_pulses ) {
  51             return 1;
  52         }
  53         pulses_comb[ k ] = sum;
  54     }
  55
  56     return 0;
  57 }
  58
  59 /* Encode quantization indices of excitation */
  60 void silk_encode_pulses(
  61     ec_enc                      *psRangeEnc,                    /* I/O  compressor data structure                   */
  62     const opus_int              signalType,                     /* I    Signal type                                 */
  63     const opus_int              quantOffsetType,                /* I    quantOffsetType                             */
  64     opus_int8                   pulses[],                       /* I    quantization indices                        */
  65     const opus_int              frame_length                    /* I    Frame length                                */
  66 )
  67 {
  68     opus_int   i, k, j, iter, bit, nLS, scale_down, RateLevelIndex = 0;
  69     opus_int32 abs_q, minSumBits_Q5, sumBits_Q5;
  70     VARDECL( opus_int, abs_pulses );
  71     VARDECL( opus_int, sum_pulses );
  72     VARDECL( opus_int, nRshifts );
  73     opus_int   pulses_comb[ 8 ];
  74     opus_int   *abs_pulses_ptr;
  75     const opus_int8 *pulses_ptr;
  76     const opus_uint8 *cdf_ptr;
  77     const opus_uint8 *nBits_ptr;
  78     SAVE_STACK;
  79
  80     silk_memset( pulses_comb, 0, 8 * sizeof( opus_int ) ); /* Fixing Valgrind reported problem*/
  81
  82     /****************************/
  83     /* Prepare for shell coding */
  84     /****************************/
  85     /* Calculate number of shell blocks */
  86     silk_assert( 1 << LOG2_SHELL_CODEC_FRAME_LENGTH == SHELL_CODEC_FRAME_LENGTH );
  87     iter = silk_RSHIFT( frame_length, LOG2_SHELL_CODEC_FRAME_LENGTH );
  88     if( iter * SHELL_CODEC_FRAME_LENGTH < frame_length ) {
  89         silk_assert( frame_length == 12 * 10 ); /* Make sure only happens for 10 ms @ 12 kHz */
  90         iter++;
  91         silk_memset( &pulses[ frame_length ], 0, SHELL_CODEC_FRAME_LENGTH * sizeof(opus_int8));
  92     }
  93
  94     /* Take the absolute value of the pulses */
  95     ALLOC( abs_pulses, iter * SHELL_CODEC_FRAME_LENGTH, opus_int );
  96     silk_assert( !( SHELL_CODEC_FRAME_LENGTH & 3 ) );
  97     for( i = 0; i < iter * SHELL_CODEC_FRAME_LENGTH; i+=4 ) {
  98         abs_pulses[i+0] = ( opus_int )silk_abs( pulses[ i + 0 ] );
  99         abs_pulses[i+1] = ( opus_int )silk_abs( pulses[ i + 1 ] );
 100         abs_pulses[i+2] = ( opus_int )silk_abs( pulses[ i + 2 ] );
 101         abs_pulses[i+3] = ( opus_int )silk_abs( pulses[ i + 3 ] );
 102     }
 103
 104     /* Calc sum pulses per shell code frame */
 105     ALLOC( sum_pulses, iter, opus_int );
 106     ALLOC( nRshifts, iter, opus_int );
 107     abs_pulses_ptr = abs_pulses;
 108     for( i = 0; i < iter; i++ ) {
 109         nRshifts[ i ] = 0;
 110
 111         while( 1 ) {
 112             /* 1+1 -> 2 */
 113             scale_down = combine_and_check( pulses_comb, abs_pulses_ptr, silk_max_pulses_table[ 0 ], 8 );
 114             /* 2+2 -> 4 */
 115             scale_down += combine_and_check( pulses_comb, pulses_comb, silk_max_pulses_table[ 1 ], 4 );
 116             /* 4+4 -> 8 */
 117             scale_down += combine_and_check( pulses_comb, pulses_comb, silk_max_pulses_table[ 2 ], 2 );
 118             /* 8+8 -> 16 */
 119             scale_down += combine_and_check( &sum_pulses[ i ], pulses_comb, silk_max_pulses_table[ 3 ], 1 );
 120
 121             if( scale_down ) {
 122                 /* We need to downscale the quantization signal */
 123                 nRshifts[ i ]++;
 124                 for( k = 0; k < SHELL_CODEC_FRAME_LENGTH; k++ ) {
 125                     abs_pulses_ptr[ k ] = silk_RSHIFT( abs_pulses_ptr[ k ], 1 );
 126                 }
 127             } else {
 128                 /* Jump out of while(1) loop and go to next shell coding frame */
 129                 break;
 130             }
 131         }
 132         abs_pulses_ptr += SHELL_CODEC_FRAME_LENGTH;
 133     }
 134
 135     /**************/
 136     /* Rate level */
 137     /**************/
 138     /* find rate level that leads to fewest bits for coding of pulses per block info */
 139     minSumBits_Q5 = silk_int32_MAX;
 140     for( k = 0; k < N_RATE_LEVELS - 1; k++ ) {
 141         nBits_ptr  = silk_pulses_per_block_BITS_Q5[ k ];
 142         sumBits_Q5 = silk_rate_levels_BITS_Q5[ signalType >> 1 ][ k ];
 143         for( i = 0; i < iter; i++ ) {
 144             if( nRshifts[ i ] > 0 ) {
 145                 sumBits_Q5 += nBits_ptr[ MAX_PULSES + 1 ];
 146             } else {
 147                 sumBits_Q5 += nBits_ptr[ sum_pulses[ i ] ];
 148             }
 149         }
 150         if( sumBits_Q5 < minSumBits_Q5 ) {
 151             minSumBits_Q5 = sumBits_Q5;
 152             RateLevelIndex = k;
 153         }
 154     }
 155     ec_enc_icdf( psRangeEnc, RateLevelIndex, silk_rate_levels_iCDF[ signalType >> 1 ], 8 );
 156
 157     /***************************************************/
 158     /* Sum-Weighted-Pulses Encoding                    */
 159     /***************************************************/
 160     cdf_ptr = silk_pulses_per_block_iCDF[ RateLevelIndex ];
 161     for( i = 0; i < iter; i++ ) {
 162         if( nRshifts[ i ] == 0 ) {
 163             ec_enc_icdf( psRangeEnc, sum_pulses[ i ], cdf_ptr, 8 );
 164         } else {
 165             ec_enc_icdf( psRangeEnc, MAX_PULSES + 1, cdf_ptr, 8 );
 166             for( k = 0; k < nRshifts[ i ] - 1; k++ ) {
 167                 ec_enc_icdf( psRangeEnc, MAX_PULSES + 1, silk_pulses_per_block_iCDF[ N_RATE_LEVELS - 1 ], 8 );
 168             }
 169             ec_enc_icdf( psRangeEnc, sum_pulses[ i ], silk_pulses_per_block_iCDF[ N_RATE_LEVELS - 1 ], 8 );
 170         }
 171     }
 172
 173     /******************/
 174     /* Shell Encoding */
 175     /******************/
 176     for( i = 0; i < iter; i++ ) {
 177         if( sum_pulses[ i ] > 0 ) {
 178             silk_shell_encoder( psRangeEnc, &abs_pulses[ i * SHELL_CODEC_FRAME_LENGTH ] );
 179         }
 180     }
 181
 182     /****************/
 183     /* LSB Encoding */
 184     /****************/
 185     for( i = 0; i < iter; i++ ) {
 186         if( nRshifts[ i ] > 0 ) {
 187             pulses_ptr = &pulses[ i * SHELL_CODEC_FRAME_LENGTH ];
 188             nLS = nRshifts[ i ] - 1;
 189             for( k = 0; k < SHELL_CODEC_FRAME_LENGTH; k++ ) {
 190                 abs_q = (opus_int8)silk_abs( pulses_ptr[ k ] );
 191                 for( j = nLS; j > 0; j-- ) {
 192                     bit = silk_RSHIFT( abs_q, j ) & 1;
 193                     ec_enc_icdf( psRangeEnc, bit, silk_lsb_iCDF, 8 );
 194                 }
 195                 bit = abs_q & 1;
 196                 ec_enc_icdf( psRangeEnc, bit, silk_lsb_iCDF, 8 );
 197             }
 198         }
 199     }
 200
 201     /****************/
 202     /* Encode signs */
 203     /****************/
 204     silk_encode_signs( psRangeEnc, pulses, frame_length, signalType, quantOffsetType, sum_pulses );
 205     RESTORE_STACK;
 206 }