Home | History | Annotate | Download | only in silk 
      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 #include "PLC.h"
     35 
     36 /****************/
     37 /* Decode frame */
     38 /****************/
     39 opus_int silk_decode_frame(
     40     silk_decoder_state          *psDec,                         /* I/O  Pointer to Silk decoder state               */
     41     ec_dec                      *psRangeDec,                    /* I/O  Compressor data structure                   */
     42     opus_int16                  pOut[],                         /* O    Pointer to output speech frame              */
     43     opus_int32                  *pN,                            /* O    Pointer to size of output frame             */
     44     opus_int                    lostFlag,                       /* I    0: no loss, 1 loss, 2 decode fec            */
     45     opus_int                    condCoding                      /* I    The type of conditional coding to use       */
     46 )
     47 {
     48     VARDECL( silk_decoder_control, psDecCtrl );
     49     opus_int         L, mv_len, ret = 0;
     50     VARDECL( opus_int, pulses );
     51     SAVE_STACK;
     52 
     53     L = psDec->frame_length;
     54     ALLOC( psDecCtrl, 1, silk_decoder_control );
     55     ALLOC( pulses, (L + SHELL_CODEC_FRAME_LENGTH - 1) &
     56                    ~(SHELL_CODEC_FRAME_LENGTH - 1), opus_int );
     57     psDecCtrl->LTP_scale_Q14 = 0;
     58 
     59     /* Safety checks */
     60     silk_assert( L > 0 && L <= MAX_FRAME_LENGTH );
     61 
     62     if(   lostFlag == FLAG_DECODE_NORMAL ||
     63         ( lostFlag == FLAG_DECODE_LBRR && psDec->LBRR_flags[ psDec->nFramesDecoded ] == 1 ) )
     64     {
     65         /*********************************************/
     66         /* Decode quantization indices of side info  */
     67         /*********************************************/
     68         silk_decode_indices( psDec, psRangeDec, psDec->nFramesDecoded, lostFlag, condCoding );
     69 
     70         /*********************************************/
     71         /* Decode quantization indices of excitation */
     72         /*********************************************/
     73         silk_decode_pulses( psRangeDec, pulses, psDec->indices.signalType,
     74                 psDec->indices.quantOffsetType, psDec->frame_length );
     75 
     76         /********************************************/
     77         /* Decode parameters and pulse signal       */
     78         /********************************************/
     79         silk_decode_parameters( psDec, psDecCtrl, condCoding );
     80 
     81         /********************************************************/
     82         /* Run inverse NSQ                                      */
     83         /********************************************************/
     84         silk_decode_core( psDec, psDecCtrl, pOut, pulses );
     85 
     86         /********************************************************/
     87         /* Update PLC state                                     */
     88         /********************************************************/
     89         silk_PLC( psDec, psDecCtrl, pOut, 0 );
     90 
     91         psDec->lossCnt = 0;
     92         psDec->prevSignalType = psDec->indices.signalType;
     93         silk_assert( psDec->prevSignalType >= 0 && psDec->prevSignalType <= 2 );
     94 
     95         /* A frame has been decoded without errors */
     96         psDec->first_frame_after_reset = 0;
     97     } else {
     98         /* Handle packet loss by extrapolation */
     99         silk_PLC( psDec, psDecCtrl, pOut, 1 );
    100     }
    101 
    102     /*************************/
    103     /* Update output buffer. */
    104     /*************************/
    105     silk_assert( psDec->ltp_mem_length >= psDec->frame_length );
    106     mv_len = psDec->ltp_mem_length - psDec->frame_length;
    107     silk_memmove( psDec->outBuf, &psDec->outBuf[ psDec->frame_length ], mv_len * sizeof(opus_int16) );
    108     silk_memcpy( &psDec->outBuf[ mv_len ], pOut, psDec->frame_length * sizeof( opus_int16 ) );
    109 
    110     /****************************************************************/
    111     /* Ensure smooth connection of extrapolated and good frames     */
    112     /****************************************************************/
    113     silk_PLC_glue_frames( psDec, pOut, L );
    114 
    115     /************************************************/
    116     /* Comfort noise generation / estimation        */
    117     /************************************************/
    118     silk_CNG( psDec, psDecCtrl, pOut, L );
    119 
    120     /* Update some decoder state variables */
    121     psDec->lagPrev = psDecCtrl->pitchL[ psDec->nb_subfr - 1 ];
    122 
    123     /* Set output frame length */
    124     *pN = L;
    125 
    126     RESTORE_STACK;
    127     return ret;
    128 }
    129