media/libopus/silk/dec_API.c

changeset 0
6474c204b198
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/media/libopus/silk/dec_API.c	Wed Dec 31 06:09:35 2014 +0100
     1.3 @@ -0,0 +1,397 @@
     1.4 +/***********************************************************************
     1.5 +Copyright (c) 2006-2011, Skype Limited. All rights reserved.
     1.6 +Redistribution and use in source and binary forms, with or without
     1.7 +modification, are permitted provided that the following conditions
     1.8 +are met:
     1.9 +- Redistributions of source code must retain the above copyright notice,
    1.10 +this list of conditions and the following disclaimer.
    1.11 +- Redistributions in binary form must reproduce the above copyright
    1.12 +notice, this list of conditions and the following disclaimer in the
    1.13 +documentation and/or other materials provided with the distribution.
    1.14 +- Neither the name of Internet Society, IETF or IETF Trust, nor the
    1.15 +names of specific contributors, may be used to endorse or promote
    1.16 +products derived from this software without specific prior written
    1.17 +permission.
    1.18 +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    1.19 +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    1.20 +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    1.21 +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    1.22 +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    1.23 +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    1.24 +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    1.25 +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    1.26 +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    1.27 +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    1.28 +POSSIBILITY OF SUCH DAMAGE.
    1.29 +***********************************************************************/
    1.30 +
    1.31 +#ifdef HAVE_CONFIG_H
    1.32 +#include "config.h"
    1.33 +#endif
    1.34 +#include "API.h"
    1.35 +#include "main.h"
    1.36 +#include "stack_alloc.h"
    1.37 +
    1.38 +/************************/
    1.39 +/* Decoder Super Struct */
    1.40 +/************************/
    1.41 +typedef struct {
    1.42 +    silk_decoder_state          channel_state[ DECODER_NUM_CHANNELS ];
    1.43 +    stereo_dec_state                sStereo;
    1.44 +    opus_int                         nChannelsAPI;
    1.45 +    opus_int                         nChannelsInternal;
    1.46 +    opus_int                         prev_decode_only_middle;
    1.47 +} silk_decoder;
    1.48 +
    1.49 +/*********************/
    1.50 +/* Decoder functions */
    1.51 +/*********************/
    1.52 +
    1.53 +opus_int silk_Get_Decoder_Size(                         /* O    Returns error code                              */
    1.54 +    opus_int                        *decSizeBytes       /* O    Number of bytes in SILK decoder state           */
    1.55 +)
    1.56 +{
    1.57 +    opus_int ret = SILK_NO_ERROR;
    1.58 +
    1.59 +    *decSizeBytes = sizeof( silk_decoder );
    1.60 +
    1.61 +    return ret;
    1.62 +}
    1.63 +
    1.64 +/* Reset decoder state */
    1.65 +opus_int silk_InitDecoder(                              /* O    Returns error code                              */
    1.66 +    void                            *decState           /* I/O  State                                           */
    1.67 +)
    1.68 +{
    1.69 +    opus_int n, ret = SILK_NO_ERROR;
    1.70 +    silk_decoder_state *channel_state = ((silk_decoder *)decState)->channel_state;
    1.71 +
    1.72 +    for( n = 0; n < DECODER_NUM_CHANNELS; n++ ) {
    1.73 +        ret  = silk_init_decoder( &channel_state[ n ] );
    1.74 +    }
    1.75 +    silk_memset(&((silk_decoder *)decState)->sStereo, 0, sizeof(((silk_decoder *)decState)->sStereo));
    1.76 +    /* Not strictly needed, but it's cleaner that way */
    1.77 +    ((silk_decoder *)decState)->prev_decode_only_middle = 0;
    1.78 +
    1.79 +    return ret;
    1.80 +}
    1.81 +
    1.82 +/* Decode a frame */
    1.83 +opus_int silk_Decode(                                   /* O    Returns error code                              */
    1.84 +    void*                           decState,           /* I/O  State                                           */
    1.85 +    silk_DecControlStruct*          decControl,         /* I/O  Control Structure                               */
    1.86 +    opus_int                        lostFlag,           /* I    0: no loss, 1 loss, 2 decode fec                */
    1.87 +    opus_int                        newPacketFlag,      /* I    Indicates first decoder call for this packet    */
    1.88 +    ec_dec                          *psRangeDec,        /* I/O  Compressor data structure                       */
    1.89 +    opus_int16                      *samplesOut,        /* O    Decoded output speech vector                    */
    1.90 +    opus_int32                      *nSamplesOut        /* O    Number of samples decoded                       */
    1.91 +)
    1.92 +{
    1.93 +    opus_int   i, n, decode_only_middle = 0, ret = SILK_NO_ERROR;
    1.94 +    opus_int32 nSamplesOutDec, LBRR_symbol;
    1.95 +    opus_int16 *samplesOut1_tmp[ 2 ];
    1.96 +    VARDECL( opus_int16, samplesOut1_tmp_storage );
    1.97 +    VARDECL( opus_int16, samplesOut2_tmp );
    1.98 +    opus_int32 MS_pred_Q13[ 2 ] = { 0 };
    1.99 +    opus_int16 *resample_out_ptr;
   1.100 +    silk_decoder *psDec = ( silk_decoder * )decState;
   1.101 +    silk_decoder_state *channel_state = psDec->channel_state;
   1.102 +    opus_int has_side;
   1.103 +    opus_int stereo_to_mono;
   1.104 +    SAVE_STACK;
   1.105 +
   1.106 +    silk_assert( decControl->nChannelsInternal == 1 || decControl->nChannelsInternal == 2 );
   1.107 +
   1.108 +    /**********************************/
   1.109 +    /* Test if first frame in payload */
   1.110 +    /**********************************/
   1.111 +    if( newPacketFlag ) {
   1.112 +        for( n = 0; n < decControl->nChannelsInternal; n++ ) {
   1.113 +            channel_state[ n ].nFramesDecoded = 0;  /* Used to count frames in packet */
   1.114 +        }
   1.115 +    }
   1.116 +
   1.117 +    /* If Mono -> Stereo transition in bitstream: init state of second channel */
   1.118 +    if( decControl->nChannelsInternal > psDec->nChannelsInternal ) {
   1.119 +        ret += silk_init_decoder( &channel_state[ 1 ] );
   1.120 +    }
   1.121 +
   1.122 +    stereo_to_mono = decControl->nChannelsInternal == 1 && psDec->nChannelsInternal == 2 &&
   1.123 +                     ( decControl->internalSampleRate == 1000*channel_state[ 0 ].fs_kHz );
   1.124 +
   1.125 +    if( channel_state[ 0 ].nFramesDecoded == 0 ) {
   1.126 +        for( n = 0; n < decControl->nChannelsInternal; n++ ) {
   1.127 +            opus_int fs_kHz_dec;
   1.128 +            if( decControl->payloadSize_ms == 0 ) {
   1.129 +                /* Assuming packet loss, use 10 ms */
   1.130 +                channel_state[ n ].nFramesPerPacket = 1;
   1.131 +                channel_state[ n ].nb_subfr = 2;
   1.132 +            } else if( decControl->payloadSize_ms == 10 ) {
   1.133 +                channel_state[ n ].nFramesPerPacket = 1;
   1.134 +                channel_state[ n ].nb_subfr = 2;
   1.135 +            } else if( decControl->payloadSize_ms == 20 ) {
   1.136 +                channel_state[ n ].nFramesPerPacket = 1;
   1.137 +                channel_state[ n ].nb_subfr = 4;
   1.138 +            } else if( decControl->payloadSize_ms == 40 ) {
   1.139 +                channel_state[ n ].nFramesPerPacket = 2;
   1.140 +                channel_state[ n ].nb_subfr = 4;
   1.141 +            } else if( decControl->payloadSize_ms == 60 ) {
   1.142 +                channel_state[ n ].nFramesPerPacket = 3;
   1.143 +                channel_state[ n ].nb_subfr = 4;
   1.144 +            } else {
   1.145 +                silk_assert( 0 );
   1.146 +                RESTORE_STACK;
   1.147 +                return SILK_DEC_INVALID_FRAME_SIZE;
   1.148 +            }
   1.149 +            fs_kHz_dec = ( decControl->internalSampleRate >> 10 ) + 1;
   1.150 +            if( fs_kHz_dec != 8 && fs_kHz_dec != 12 && fs_kHz_dec != 16 ) {
   1.151 +                silk_assert( 0 );
   1.152 +                RESTORE_STACK;
   1.153 +                return SILK_DEC_INVALID_SAMPLING_FREQUENCY;
   1.154 +            }
   1.155 +            ret += silk_decoder_set_fs( &channel_state[ n ], fs_kHz_dec, decControl->API_sampleRate );
   1.156 +        }
   1.157 +    }
   1.158 +
   1.159 +    if( decControl->nChannelsAPI == 2 && decControl->nChannelsInternal == 2 && ( psDec->nChannelsAPI == 1 || psDec->nChannelsInternal == 1 ) ) {
   1.160 +        silk_memset( psDec->sStereo.pred_prev_Q13, 0, sizeof( psDec->sStereo.pred_prev_Q13 ) );
   1.161 +        silk_memset( psDec->sStereo.sSide, 0, sizeof( psDec->sStereo.sSide ) );
   1.162 +        silk_memcpy( &channel_state[ 1 ].resampler_state, &channel_state[ 0 ].resampler_state, sizeof( silk_resampler_state_struct ) );
   1.163 +    }
   1.164 +    psDec->nChannelsAPI      = decControl->nChannelsAPI;
   1.165 +    psDec->nChannelsInternal = decControl->nChannelsInternal;
   1.166 +
   1.167 +    if( decControl->API_sampleRate > (opus_int32)MAX_API_FS_KHZ * 1000 || decControl->API_sampleRate < 8000 ) {
   1.168 +        ret = SILK_DEC_INVALID_SAMPLING_FREQUENCY;
   1.169 +        RESTORE_STACK;
   1.170 +        return( ret );
   1.171 +    }
   1.172 +
   1.173 +    if( lostFlag != FLAG_PACKET_LOST && channel_state[ 0 ].nFramesDecoded == 0 ) {
   1.174 +        /* First decoder call for this payload */
   1.175 +        /* Decode VAD flags and LBRR flag */
   1.176 +        for( n = 0; n < decControl->nChannelsInternal; n++ ) {
   1.177 +            for( i = 0; i < channel_state[ n ].nFramesPerPacket; i++ ) {
   1.178 +                channel_state[ n ].VAD_flags[ i ] = ec_dec_bit_logp(psRangeDec, 1);
   1.179 +            }
   1.180 +            channel_state[ n ].LBRR_flag = ec_dec_bit_logp(psRangeDec, 1);
   1.181 +        }
   1.182 +        /* Decode LBRR flags */
   1.183 +        for( n = 0; n < decControl->nChannelsInternal; n++ ) {
   1.184 +            silk_memset( channel_state[ n ].LBRR_flags, 0, sizeof( channel_state[ n ].LBRR_flags ) );
   1.185 +            if( channel_state[ n ].LBRR_flag ) {
   1.186 +                if( channel_state[ n ].nFramesPerPacket == 1 ) {
   1.187 +                    channel_state[ n ].LBRR_flags[ 0 ] = 1;
   1.188 +                } else {
   1.189 +                    LBRR_symbol = ec_dec_icdf( psRangeDec, silk_LBRR_flags_iCDF_ptr[ channel_state[ n ].nFramesPerPacket - 2 ], 8 ) + 1;
   1.190 +                    for( i = 0; i < channel_state[ n ].nFramesPerPacket; i++ ) {
   1.191 +                        channel_state[ n ].LBRR_flags[ i ] = silk_RSHIFT( LBRR_symbol, i ) & 1;
   1.192 +                    }
   1.193 +                }
   1.194 +            }
   1.195 +        }
   1.196 +
   1.197 +        if( lostFlag == FLAG_DECODE_NORMAL ) {
   1.198 +            /* Regular decoding: skip all LBRR data */
   1.199 +            for( i = 0; i < channel_state[ 0 ].nFramesPerPacket; i++ ) {
   1.200 +                for( n = 0; n < decControl->nChannelsInternal; n++ ) {
   1.201 +                    if( channel_state[ n ].LBRR_flags[ i ] ) {
   1.202 +                        opus_int pulses[ MAX_FRAME_LENGTH ];
   1.203 +                        opus_int condCoding;
   1.204 +
   1.205 +                        if( decControl->nChannelsInternal == 2 && n == 0 ) {
   1.206 +                            silk_stereo_decode_pred( psRangeDec, MS_pred_Q13 );
   1.207 +                            if( channel_state[ 1 ].LBRR_flags[ i ] == 0 ) {
   1.208 +                                silk_stereo_decode_mid_only( psRangeDec, &decode_only_middle );
   1.209 +                            }
   1.210 +                        }
   1.211 +                        /* Use conditional coding if previous frame available */
   1.212 +                        if( i > 0 && channel_state[ n ].LBRR_flags[ i - 1 ] ) {
   1.213 +                            condCoding = CODE_CONDITIONALLY;
   1.214 +                        } else {
   1.215 +                            condCoding = CODE_INDEPENDENTLY;
   1.216 +                        }
   1.217 +                        silk_decode_indices( &channel_state[ n ], psRangeDec, i, 1, condCoding );
   1.218 +                        silk_decode_pulses( psRangeDec, pulses, channel_state[ n ].indices.signalType,
   1.219 +                            channel_state[ n ].indices.quantOffsetType, channel_state[ n ].frame_length );
   1.220 +                    }
   1.221 +                }
   1.222 +            }
   1.223 +        }
   1.224 +    }
   1.225 +
   1.226 +    /* Get MS predictor index */
   1.227 +    if( decControl->nChannelsInternal == 2 ) {
   1.228 +        if(   lostFlag == FLAG_DECODE_NORMAL ||
   1.229 +            ( lostFlag == FLAG_DECODE_LBRR && channel_state[ 0 ].LBRR_flags[ channel_state[ 0 ].nFramesDecoded ] == 1 ) )
   1.230 +        {
   1.231 +            silk_stereo_decode_pred( psRangeDec, MS_pred_Q13 );
   1.232 +            /* For LBRR data, decode mid-only flag only if side-channel's LBRR flag is false */
   1.233 +            if( ( lostFlag == FLAG_DECODE_NORMAL && channel_state[ 1 ].VAD_flags[ channel_state[ 0 ].nFramesDecoded ] == 0 ) ||
   1.234 +                ( lostFlag == FLAG_DECODE_LBRR && channel_state[ 1 ].LBRR_flags[ channel_state[ 0 ].nFramesDecoded ] == 0 ) )
   1.235 +            {
   1.236 +                silk_stereo_decode_mid_only( psRangeDec, &decode_only_middle );
   1.237 +            } else {
   1.238 +                decode_only_middle = 0;
   1.239 +            }
   1.240 +        } else {
   1.241 +            for( n = 0; n < 2; n++ ) {
   1.242 +                MS_pred_Q13[ n ] = psDec->sStereo.pred_prev_Q13[ n ];
   1.243 +            }
   1.244 +        }
   1.245 +    }
   1.246 +
   1.247 +    /* Reset side channel decoder prediction memory for first frame with side coding */
   1.248 +    if( decControl->nChannelsInternal == 2 && decode_only_middle == 0 && psDec->prev_decode_only_middle == 1 ) {
   1.249 +        silk_memset( psDec->channel_state[ 1 ].outBuf, 0, sizeof(psDec->channel_state[ 1 ].outBuf) );
   1.250 +        silk_memset( psDec->channel_state[ 1 ].sLPC_Q14_buf, 0, sizeof(psDec->channel_state[ 1 ].sLPC_Q14_buf) );
   1.251 +        psDec->channel_state[ 1 ].lagPrev        = 100;
   1.252 +        psDec->channel_state[ 1 ].LastGainIndex  = 10;
   1.253 +        psDec->channel_state[ 1 ].prevSignalType = TYPE_NO_VOICE_ACTIVITY;
   1.254 +        psDec->channel_state[ 1 ].first_frame_after_reset = 1;
   1.255 +    }
   1.256 +
   1.257 +    ALLOC( samplesOut1_tmp_storage,
   1.258 +           decControl->nChannelsInternal*(
   1.259 +               channel_state[ 0 ].frame_length + 2 ),
   1.260 +           opus_int16 );
   1.261 +    samplesOut1_tmp[ 0 ] = samplesOut1_tmp_storage;
   1.262 +    samplesOut1_tmp[ 1 ] = samplesOut1_tmp_storage
   1.263 +                           + channel_state[ 0 ].frame_length + 2;
   1.264 +
   1.265 +    if( lostFlag == FLAG_DECODE_NORMAL ) {
   1.266 +        has_side = !decode_only_middle;
   1.267 +    } else {
   1.268 +        has_side = !psDec->prev_decode_only_middle
   1.269 +              || (decControl->nChannelsInternal == 2 && lostFlag == FLAG_DECODE_LBRR && channel_state[1].LBRR_flags[ channel_state[1].nFramesDecoded ] == 1 );
   1.270 +    }
   1.271 +    /* Call decoder for one frame */
   1.272 +    for( n = 0; n < decControl->nChannelsInternal; n++ ) {
   1.273 +        if( n == 0 || has_side ) {
   1.274 +            opus_int FrameIndex;
   1.275 +            opus_int condCoding;
   1.276 +
   1.277 +            FrameIndex = channel_state[ 0 ].nFramesDecoded - n;
   1.278 +            /* Use independent coding if no previous frame available */
   1.279 +            if( FrameIndex <= 0 ) {
   1.280 +                condCoding = CODE_INDEPENDENTLY;
   1.281 +            } else if( lostFlag == FLAG_DECODE_LBRR ) {
   1.282 +                condCoding = channel_state[ n ].LBRR_flags[ FrameIndex - 1 ] ? CODE_CONDITIONALLY : CODE_INDEPENDENTLY;
   1.283 +            } else if( n > 0 && psDec->prev_decode_only_middle ) {
   1.284 +                /* If we skipped a side frame in this packet, we don't
   1.285 +                   need LTP scaling; the LTP state is well-defined. */
   1.286 +                condCoding = CODE_INDEPENDENTLY_NO_LTP_SCALING;
   1.287 +            } else {
   1.288 +                condCoding = CODE_CONDITIONALLY;
   1.289 +            }
   1.290 +            ret += silk_decode_frame( &channel_state[ n ], psRangeDec, &samplesOut1_tmp[ n ][ 2 ], &nSamplesOutDec, lostFlag, condCoding);
   1.291 +        } else {
   1.292 +            silk_memset( &samplesOut1_tmp[ n ][ 2 ], 0, nSamplesOutDec * sizeof( opus_int16 ) );
   1.293 +        }
   1.294 +        channel_state[ n ].nFramesDecoded++;
   1.295 +    }
   1.296 +
   1.297 +    if( decControl->nChannelsAPI == 2 && decControl->nChannelsInternal == 2 ) {
   1.298 +        /* Convert Mid/Side to Left/Right */
   1.299 +        silk_stereo_MS_to_LR( &psDec->sStereo, samplesOut1_tmp[ 0 ], samplesOut1_tmp[ 1 ], MS_pred_Q13, channel_state[ 0 ].fs_kHz, nSamplesOutDec );
   1.300 +    } else {
   1.301 +        /* Buffering */
   1.302 +        silk_memcpy( samplesOut1_tmp[ 0 ], psDec->sStereo.sMid, 2 * sizeof( opus_int16 ) );
   1.303 +        silk_memcpy( psDec->sStereo.sMid, &samplesOut1_tmp[ 0 ][ nSamplesOutDec ], 2 * sizeof( opus_int16 ) );
   1.304 +    }
   1.305 +
   1.306 +    /* Number of output samples */
   1.307 +    *nSamplesOut = silk_DIV32( nSamplesOutDec * decControl->API_sampleRate, silk_SMULBB( channel_state[ 0 ].fs_kHz, 1000 ) );
   1.308 +
   1.309 +    /* Set up pointers to temp buffers */
   1.310 +    ALLOC( samplesOut2_tmp,
   1.311 +           decControl->nChannelsAPI == 2 ? *nSamplesOut : ALLOC_NONE, opus_int16 );
   1.312 +    if( decControl->nChannelsAPI == 2 ) {
   1.313 +        resample_out_ptr = samplesOut2_tmp;
   1.314 +    } else {
   1.315 +        resample_out_ptr = samplesOut;
   1.316 +    }
   1.317 +
   1.318 +    for( n = 0; n < silk_min( decControl->nChannelsAPI, decControl->nChannelsInternal ); n++ ) {
   1.319 +
   1.320 +        /* Resample decoded signal to API_sampleRate */
   1.321 +        ret += silk_resampler( &channel_state[ n ].resampler_state, resample_out_ptr, &samplesOut1_tmp[ n ][ 1 ], nSamplesOutDec );
   1.322 +
   1.323 +        /* Interleave if stereo output and stereo stream */
   1.324 +        if( decControl->nChannelsAPI == 2 ) {
   1.325 +            for( i = 0; i < *nSamplesOut; i++ ) {
   1.326 +                samplesOut[ n + 2 * i ] = resample_out_ptr[ i ];
   1.327 +            }
   1.328 +        }
   1.329 +    }
   1.330 +
   1.331 +    /* Create two channel output from mono stream */
   1.332 +    if( decControl->nChannelsAPI == 2 && decControl->nChannelsInternal == 1 ) {
   1.333 +        if ( stereo_to_mono ){
   1.334 +            /* Resample right channel for newly collapsed stereo just in case
   1.335 +               we weren't doing collapsing when switching to mono */
   1.336 +            ret += silk_resampler( &channel_state[ 1 ].resampler_state, resample_out_ptr, &samplesOut1_tmp[ 0 ][ 1 ], nSamplesOutDec );
   1.337 +
   1.338 +            for( i = 0; i < *nSamplesOut; i++ ) {
   1.339 +                samplesOut[ 1 + 2 * i ] = resample_out_ptr[ i ];
   1.340 +            }
   1.341 +        } else {
   1.342 +            for( i = 0; i < *nSamplesOut; i++ ) {
   1.343 +                samplesOut[ 1 + 2 * i ] = samplesOut[ 0 + 2 * i ];
   1.344 +            }
   1.345 +        }
   1.346 +    }
   1.347 +
   1.348 +    /* Export pitch lag, measured at 48 kHz sampling rate */
   1.349 +    if( channel_state[ 0 ].prevSignalType == TYPE_VOICED ) {
   1.350 +        int mult_tab[ 3 ] = { 6, 4, 3 };
   1.351 +        decControl->prevPitchLag = channel_state[ 0 ].lagPrev * mult_tab[ ( channel_state[ 0 ].fs_kHz - 8 ) >> 2 ];
   1.352 +    } else {
   1.353 +        decControl->prevPitchLag = 0;
   1.354 +    }
   1.355 +
   1.356 +    if( lostFlag == FLAG_PACKET_LOST ) {
   1.357 +       /* On packet loss, remove the gain clamping to prevent having the energy "bounce back"
   1.358 +          if we lose packets when the energy is going down */
   1.359 +       for ( i = 0; i < psDec->nChannelsInternal; i++ )
   1.360 +          psDec->channel_state[ i ].LastGainIndex = 10;
   1.361 +    } else {
   1.362 +       psDec->prev_decode_only_middle = decode_only_middle;
   1.363 +    }
   1.364 +    RESTORE_STACK;
   1.365 +    return ret;
   1.366 +}
   1.367 +
   1.368 +#if 0
   1.369 +/* Getting table of contents for a packet */
   1.370 +opus_int silk_get_TOC(
   1.371 +    const opus_uint8                *payload,           /* I    Payload data                                */
   1.372 +    const opus_int                  nBytesIn,           /* I    Number of input bytes                       */
   1.373 +    const opus_int                  nFramesPerPayload,  /* I    Number of SILK frames per payload           */
   1.374 +    silk_TOC_struct                 *Silk_TOC           /* O    Type of content                             */
   1.375 +)
   1.376 +{
   1.377 +    opus_int i, flags, ret = SILK_NO_ERROR;
   1.378 +
   1.379 +    if( nBytesIn < 1 ) {
   1.380 +        return -1;
   1.381 +    }
   1.382 +    if( nFramesPerPayload < 0 || nFramesPerPayload > 3 ) {
   1.383 +        return -1;
   1.384 +    }
   1.385 +
   1.386 +    silk_memset( Silk_TOC, 0, sizeof( *Silk_TOC ) );
   1.387 +
   1.388 +    /* For stereo, extract the flags for the mid channel */
   1.389 +    flags = silk_RSHIFT( payload[ 0 ], 7 - nFramesPerPayload ) & ( silk_LSHIFT( 1, nFramesPerPayload + 1 ) - 1 );
   1.390 +
   1.391 +    Silk_TOC->inbandFECFlag = flags & 1;
   1.392 +    for( i = nFramesPerPayload - 1; i >= 0 ; i-- ) {
   1.393 +        flags = silk_RSHIFT( flags, 1 );
   1.394 +        Silk_TOC->VADFlags[ i ] = flags & 1;
   1.395 +        Silk_TOC->VADFlag |= flags & 1;
   1.396 +    }
   1.397 +
   1.398 +    return ret;
   1.399 +}
   1.400 +#endif

mercurial