1/***********************************************************************
2Copyright (c) 2006-2011, Skype Limited. All rights reserved.
3Redistribution and use in source and binary forms, with or without
4modification, are permitted provided that the following conditions
5are met:
6- Redistributions of source code must retain the above copyright notice,
7this list of conditions and the following disclaimer.
8- Redistributions in binary form must reproduce the above copyright
9notice, this list of conditions and the following disclaimer in the
10documentation and/or other materials provided with the distribution.
11- Neither the name of Internet Society, IETF or IETF Trust, nor the
12names of specific contributors, may be used to endorse or promote
13products derived from this software without specific prior written
14permission.
15THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
19LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25POSSIBILITY 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/****************/
39opus_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