Coverage Report

Created: 2025-07-01 07:05

/src/opus/silk/control_SNR.c
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Source
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/***********************************************************************
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Copyright (c) 2006-2011, Skype Limited. All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions
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are met:
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- Redistributions of source code must retain the above copyright notice,
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this list of conditions and the following disclaimer.
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- Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in the
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documentation and/or other materials provided with the distribution.
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- Neither the name of Internet Society, IETF or IETF Trust, nor the
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names of specific contributors, may be used to endorse or promote
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products derived from this software without specific prior written
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permission.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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POSSIBILITY OF SUCH DAMAGE.
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***********************************************************************/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include "main.h"
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#include "tuning_parameters.h"
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/* These tables hold SNR values divided by 21 (so they fit in 8 bits)
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   for different target bitrates spaced at 400 bps interval. The first
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   10 values are omitted (0-4 kb/s) because they're all zeros.
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   These tables were obtained by running different SNRs through the
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   encoder and measuring the active bitrate. */
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static const unsigned char silk_TargetRate_NB_21[117 - 10] = {
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                                              0, 15, 39, 52, 61, 68,
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     74, 79, 84, 88, 92, 95, 99,102,105,108,111,114,117,119,122,124,
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    126,129,131,133,135,137,139,142,143,145,147,149,151,153,155,157,
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    158,160,162,163,165,167,168,170,171,173,174,176,177,179,180,182,
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    183,185,186,187,189,190,192,193,194,196,197,199,200,201,203,204,
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    205,207,208,209,211,212,213,215,216,217,219,220,221,223,224,225,
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    227,228,230,231,232,234,235,236,238,239,241,242,243,245,246,248,
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    249,250,252,253,255
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};
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static const unsigned char silk_TargetRate_MB_21[165 - 10] = {
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                                              0,  0, 28, 43, 52, 59,
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     65, 70, 74, 78, 81, 85, 87, 90, 93, 95, 98,100,102,105,107,109,
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    111,113,115,116,118,120,122,123,125,127,128,130,131,133,134,136,
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    137,138,140,141,143,144,145,147,148,149,151,152,153,154,156,157,
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    158,159,160,162,163,164,165,166,167,168,169,171,172,173,174,175,
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    176,177,178,179,180,181,182,183,184,185,186,187,188,188,189,190,
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    191,192,193,194,195,196,197,198,199,200,201,202,203,203,204,205,
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    206,207,208,209,210,211,212,213,214,214,215,216,217,218,219,220,
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    221,222,223,224,224,225,226,227,228,229,230,231,232,233,234,235,
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    236,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,
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    251,252,253,254,255
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};
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static const unsigned char silk_TargetRate_WB_21[201 - 10] = {
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                                              0,  0,  0,  8, 29, 41,
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     49, 56, 62, 66, 70, 74, 77, 80, 83, 86, 88, 91, 93, 95, 97, 99,
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    101,103,105,107,108,110,112,113,115,116,118,119,121,122,123,125,
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    126,127,129,130,131,132,134,135,136,137,138,140,141,142,143,144,
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    145,146,147,148,149,150,151,152,153,154,156,157,158,159,159,160,
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    161,162,163,164,165,166,167,168,169,170,171,171,172,173,174,175,
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    176,177,177,178,179,180,181,181,182,183,184,185,185,186,187,188,
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    189,189,190,191,192,192,193,194,195,195,196,197,198,198,199,200,
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    200,201,202,203,203,204,205,206,206,207,208,209,209,210,211,211,
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    212,213,214,214,215,216,216,217,218,219,219,220,221,221,222,223,
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    224,224,225,226,226,227,228,229,229,230,231,232,232,233,234,234,
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    235,236,237,237,238,239,240,240,241,242,243,243,244,245,246,246,
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    247,248,249,249,250,251,252,253,255
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};
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/* Control SNR of redidual quantizer */
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opus_int silk_control_SNR(
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    silk_encoder_state          *psEncC,                        /* I/O  Pointer to Silk encoder state               */
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    opus_int32                  TargetRate_bps                  /* I    Target max bitrate (bps)                    */
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)
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309k
{
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309k
    int id;
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309k
    int bound;
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309k
    const unsigned char *snr_table;
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309k
    psEncC->TargetRate_bps = TargetRate_bps;
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309k
    if( psEncC->nb_subfr == 2 ) {
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70.4k
        TargetRate_bps -= 2000 + psEncC->fs_kHz/16;
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70.4k
    }
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309k
    if( psEncC->fs_kHz == 8 ) {
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220k
        bound = sizeof(silk_TargetRate_NB_21);
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220k
        snr_table = silk_TargetRate_NB_21;
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220k
    } else if( psEncC->fs_kHz == 12 ) {
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27.0k
        bound = sizeof(silk_TargetRate_MB_21);
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27.0k
        snr_table = silk_TargetRate_MB_21;
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62.6k
    } else {
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62.6k
        bound = sizeof(silk_TargetRate_WB_21);
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62.6k
        snr_table = silk_TargetRate_WB_21;
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62.6k
    }
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309k
    id = (TargetRate_bps+200)/400;
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309k
    id = silk_min(id - 10, bound-1);
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309k
    if( id <= 0 ) {
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2.38k
        psEncC->SNR_dB_Q7 = 0;
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307k
    } else {
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307k
        psEncC->SNR_dB_Q7 = snr_table[id]*21;
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307k
    }
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    return SILK_NO_ERROR;
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}