ref: 3b1928ce3e6943377d9b1d96b9b95ca27e8e693c
dir: /silk/decode_indices.c/
/***********************************************************************
Copyright (c) 2006-2011, Skype Limited. All rights reserved.
Redistribution and use in source and binary forms, with or without
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are met:
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- Redistributions in binary form must reproduce the above copyright
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names of specific contributors, may be used to endorse or promote
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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***********************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "main.h"
/* Decode side-information parameters from payload */
void silk_decode_indices(
silk_decoder_state *psDec, /* I/O State */
ec_dec *psRangeDec, /* I/O Compressor data structure */
opus_int FrameIndex, /* I Frame number */
opus_int decode_LBRR, /* I Flag indicating LBRR data is being decoded */
opus_int condCoding /* I The type of conditional coding to use */
)
{
opus_int i, k, Ix;
opus_int decode_absolute_lagIndex, delta_lagIndex;
opus_int16 ec_ix[ MAX_LPC_ORDER ];
opus_uint8 pred_Q8[ MAX_LPC_ORDER ];
/*******************************************/
/* Decode signal type and quantizer offset */
/*******************************************/
if( decode_LBRR || psDec->VAD_flags[ FrameIndex ] ) {
Ix = ec_dec_icdf( psRangeDec, silk_type_offset_VAD_iCDF, 8 ) + 2;
} else {
Ix = ec_dec_icdf( psRangeDec, silk_type_offset_no_VAD_iCDF, 8 );
}
psDec->indices.signalType = (opus_int8)silk_RSHIFT( Ix, 1 );
psDec->indices.quantOffsetType = (opus_int8)( Ix & 1 );
/****************/
/* Decode gains */
/****************/
/* First subframe */
if( condCoding == CODE_CONDITIONALLY ) {
/* Conditional coding */
psDec->indices.GainsIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );
} else {
/* Independent coding, in two stages: MSB bits followed by 3 LSBs */
psDec->indices.GainsIndices[ 0 ] = (opus_int8)silk_LSHIFT( ec_dec_icdf( psRangeDec, silk_gain_iCDF[ psDec->indices.signalType ], 8 ), 3 );
psDec->indices.GainsIndices[ 0 ] += (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform8_iCDF, 8 );
}
/* Remaining subframes */
for( i = 1; i < psDec->nb_subfr; i++ ) {
psDec->indices.GainsIndices[ i ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );
}
/**********************/
/* Decode LSF Indices */
/**********************/
psDec->indices.NLSFIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->CB1_iCDF[ ( psDec->indices.signalType >> 1 ) * psDec->psNLSF_CB->nVectors ], 8 );
silk_NLSF_unpack( ec_ix, pred_Q8, psDec->psNLSF_CB, psDec->indices.NLSFIndices[ 0 ] );
silk_assert( psDec->psNLSF_CB->order == psDec->LPC_order );
for( i = 0; i < psDec->psNLSF_CB->order; i++ ) {
Ix = ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->ec_iCDF[ ec_ix[ i ] ], 8 );
if( Ix == 0 ) {
Ix -= ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );
} else if( Ix == 2 * NLSF_QUANT_MAX_AMPLITUDE ) {
Ix += ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );
}
psDec->indices.NLSFIndices[ i+1 ] = (opus_int8)( Ix - NLSF_QUANT_MAX_AMPLITUDE );
}
/* Decode LSF interpolation factor */
if( psDec->nb_subfr == MAX_NB_SUBFR ) {
psDec->indices.NLSFInterpCoef_Q2 = (opus_int8)ec_dec_icdf( psRangeDec, silk_NLSF_interpolation_factor_iCDF, 8 );
} else {
psDec->indices.NLSFInterpCoef_Q2 = 4;
}
if( psDec->indices.signalType == TYPE_VOICED )
{
/*********************/
/* Decode pitch lags */
/*********************/
/* Get lag index */
decode_absolute_lagIndex = 1;
if( condCoding == CODE_CONDITIONALLY && psDec->ec_prevSignalType == TYPE_VOICED ) {
/* Decode Delta index */
delta_lagIndex = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_delta_iCDF, 8 );
if( delta_lagIndex > 0 ) {
delta_lagIndex = delta_lagIndex - 9;
psDec->indices.lagIndex = (opus_int16)( psDec->ec_prevLagIndex + delta_lagIndex );
decode_absolute_lagIndex = 0;
}
}
if( decode_absolute_lagIndex ) {
/* Absolute decoding */
psDec->indices.lagIndex = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_lag_iCDF, 8 ) * silk_RSHIFT( psDec->fs_kHz, 1 );
psDec->indices.lagIndex += (opus_int16)ec_dec_icdf( psRangeDec, psDec->pitch_lag_low_bits_iCDF, 8 );
}
psDec->ec_prevLagIndex = psDec->indices.lagIndex;
/* Get countour index */
psDec->indices.contourIndex = (opus_int8)ec_dec_icdf( psRangeDec, psDec->pitch_contour_iCDF, 8 );
/********************/
/* Decode LTP gains */
/********************/
/* Decode PERIndex value */
psDec->indices.PERIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_per_index_iCDF, 8 );
for( k = 0; k < psDec->nb_subfr; k++ ) {
psDec->indices.LTPIndex[ k ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_gain_iCDF_ptrs[ psDec->indices.PERIndex ], 8 );
}
/**********************/
/* Decode LTP scaling */
/**********************/
if( condCoding == CODE_INDEPENDENTLY ) {
psDec->indices.LTP_scaleIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTPscale_iCDF, 8 );
} else {
psDec->indices.LTP_scaleIndex = 0;
}
}
psDec->ec_prevSignalType = psDec->indices.signalType;
/***************/
/* Decode seed */
/***************/
psDec->indices.Seed = (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform4_iCDF, 8 );
}