ref: 310af750eb5726b4143a43208f2bc03677c6f5db
dir: /silk/SKP_Silk_dec_API.c/
/***********************************************************************
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BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
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***********************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "SKP_Silk_SDK_API.h"
#include "SKP_Silk_main.h"
/* Decoder Super Struct */
typedef struct {
SKP_Silk_decoder_state channel_state[ DECODER_NUM_CHANNELS ];
stereo_state sStereo;
SKP_int nChannels;
} SKP_Silk_decoder;
/*********************/
/* Decoder functions */
/*********************/
SKP_int SKP_Silk_SDK_Get_Decoder_Size( SKP_int32 *decSizeBytes )
{
SKP_int ret = SKP_SILK_NO_ERROR;
*decSizeBytes = sizeof( SKP_Silk_decoder );
return ret;
}
/* Reset decoder state */
SKP_int SKP_Silk_SDK_InitDecoder(
void* decState /* I/O: State */
)
{
SKP_int n, ret = SKP_SILK_NO_ERROR;
SKP_Silk_decoder_state *channel_state = ((SKP_Silk_decoder *)decState)->channel_state;
for( n = 0; n < DECODER_NUM_CHANNELS; n++ ) {
ret = SKP_Silk_init_decoder( &channel_state[ n ] );
}
return ret;
}
/* Decode a frame */
SKP_int SKP_Silk_SDK_Decode(
void* decState, /* I/O: State */
SKP_SILK_SDK_DecControlStruct* decControl, /* I/O: Control Structure */
SKP_int lostFlag, /* I: 0: no loss, 1 loss, 2 decode FEC */
SKP_int newPacketFlag, /* I: Indicates first decoder call for this packet */
ec_dec *psRangeDec, /* I/O Compressor data structure */
SKP_int16 *samplesOut, /* O: Decoded output speech vector */
SKP_int32 *nSamplesOut /* O: Number of samples decoded */
)
{
SKP_int i, n, prev_fs_kHz, doResample, flags, nFlags, MS_predictorIx, ret = SKP_SILK_NO_ERROR;
SKP_int32 nSamplesOutDec, LBRR_symbol;
SKP_int16 samplesOut1_tmp[ 2 * MAX_FS_KHZ * MAX_FRAME_LENGTH_MS ];
SKP_int16 samplesOut2_tmp[ MAX_API_FS_KHZ * MAX_FRAME_LENGTH_MS ];
SKP_int16 *dec_out_ptr, *resample_out_ptr;
SKP_Silk_decoder *psDec = ( SKP_Silk_decoder * )decState;
SKP_Silk_decoder_state *channel_state = psDec->channel_state;
/**********************************/
/* Test if first frame in payload */
/**********************************/
if( newPacketFlag ) {
for( n = 0; n < decControl->nChannels; n++ ) {
channel_state[ n ].nFramesDecoded = 0; /* Used to count frames in packet */
}
}
/* Save previous sample frequency */
prev_fs_kHz = channel_state[ 0 ].fs_kHz;
if( decControl->nChannels > psDec->nChannels ) {
/* Mono -> Stereo transition: init state of second channel and stereo state */
SKP_memset( &psDec->sStereo, 0, sizeof( psDec->sStereo ) );
ret += SKP_Silk_init_decoder( &channel_state[ 1 ] );
}
psDec->nChannels = decControl->nChannels;
for( n = 0; n < decControl->nChannels; n++ ) {
if( channel_state[ n ].nFramesDecoded == 0 ) {
SKP_int fs_kHz_dec;
if( decControl->payloadSize_ms == 10 ) {
channel_state[ n ].nFramesPerPacket = 1;
channel_state[ n ].nb_subfr = 2;
} else if( decControl->payloadSize_ms == 20 ) {
channel_state[ n ].nFramesPerPacket = 1;
channel_state[ n ].nb_subfr = 4;
} else if( decControl->payloadSize_ms == 40 ) {
channel_state[ n ].nFramesPerPacket = 2;
channel_state[ n ].nb_subfr = 4;
} else if( decControl->payloadSize_ms == 60 ) {
channel_state[ n ].nFramesPerPacket = 3;
channel_state[ n ].nb_subfr = 4;
} else {
SKP_assert( 0 );
return SKP_SILK_DEC_INVALID_FRAME_SIZE;
}
fs_kHz_dec = ( decControl->internalSampleRate >> 10 ) + 1;
if( fs_kHz_dec != 8 && fs_kHz_dec != 12 && fs_kHz_dec != 16 ) {
SKP_assert( 0 );
return SKP_SILK_DEC_INVALID_SAMPLING_FREQUENCY;
}
SKP_Silk_decoder_set_fs( &channel_state[ n ], fs_kHz_dec );
}
}
if( decControl->API_sampleRate > MAX_API_FS_KHZ * 1000 || decControl->API_sampleRate < 8000 ) {
ret = SKP_SILK_DEC_INVALID_SAMPLING_FREQUENCY;
return( ret );
}
doResample = SKP_SMULBB( channel_state[ 0 ].fs_kHz, 1000 ) != decControl->API_sampleRate;
/* Set up pointers to temp buffers */
if( doResample || decControl->nChannels == 2 ) {
dec_out_ptr = samplesOut1_tmp;
} else {
dec_out_ptr = samplesOut;
}
if( decControl->nChannels == 2 ) {
resample_out_ptr = samplesOut2_tmp;
} else {
resample_out_ptr = samplesOut;
}
if( lostFlag != FLAG_PACKET_LOST && channel_state[ 0 ].nFramesDecoded == 0 ) {
/* First decoder call for this payload */
nFlags = SKP_SMULBB( decControl->nChannels, channel_state[ 0 ].nFramesPerPacket + 1 );
flags = SKP_RSHIFT( psRangeDec->buf[ 0 ], 8 - nFlags ) & ( SKP_LSHIFT( 1, nFlags ) - 1 );
for( i = 0; i < nFlags; i++ ) {
ec_dec_icdf( psRangeDec, SKP_Silk_uniform2_iCDF, 8 );
}
/* Decode VAD flags and LBRR flag */
for( n = decControl->nChannels - 1; n >= 0; n-- ) {
channel_state[ n ].LBRR_flag = flags & 1;
flags = SKP_RSHIFT( flags, 1 );
for( i = channel_state[ n ].nFramesPerPacket - 1; i >= 0 ; i-- ) {
channel_state[ n ].VAD_flags[ i ] = flags & 1;
flags = SKP_RSHIFT( flags, 1 );
}
}
/* Decode LBRR flags */
for( n = 0; n < decControl->nChannels; n++ ) {
SKP_memset( channel_state[ n ].LBRR_flags, 0, sizeof( channel_state[ n ].LBRR_flags ) );
if( channel_state[ n ].LBRR_flag ) {
if( channel_state[ n ].nFramesPerPacket == 1 ) {
channel_state[ n ].LBRR_flags[ 0 ] = 1;
} else {
LBRR_symbol = ec_dec_icdf( psRangeDec, SKP_Silk_LBRR_flags_iCDF_ptr[ channel_state[ n ].nFramesPerPacket - 2 ], 8 ) + 1;
for( i = 0; i < channel_state[ n ].nFramesPerPacket; i++ ) {
channel_state[ n ].LBRR_flags[ i ] = SKP_RSHIFT( LBRR_symbol, i ) & 1;
}
}
}
}
if( lostFlag == FLAG_DECODE_NORMAL ) {
/* Regular decoding: skip all LBRR data */
for( i = 0; i < channel_state[ 0 ].nFramesPerPacket; i++ ) {
for( n = 0; n < decControl->nChannels; n++ ) {
if( channel_state[ n ].LBRR_flags[ i ] ) {
SKP_int pulses[ MAX_FRAME_LENGTH ];
SKP_Silk_decode_indices( &channel_state[ n ], psRangeDec, i, 1 );
SKP_Silk_decode_pulses( psRangeDec, pulses, channel_state[ n ].indices.signalType,
channel_state[ n ].indices.quantOffsetType, channel_state[ n ].frame_length );
}
}
}
}
}
/* Get MS predictor index */
if( decControl->nChannels == 2 ) {
MS_predictorIx = ec_dec_icdf( psRangeDec, SKP_Silk_stereo_predictor_iCDF, 8 );
}
/* Call decoder for one frame */
for( n = 0; n < decControl->nChannels; n++ ) {
ret += SKP_Silk_decode_frame( &channel_state[ n ], psRangeDec, &dec_out_ptr[ n * MAX_FS_KHZ * MAX_FRAME_LENGTH_MS ], &nSamplesOutDec, lostFlag );
}
/* Convert Mid/Side to Left/Right */
if( decControl->nChannels == 2 ) {
SKP_Silk_stereo_MS_to_LR( &psDec->sStereo, dec_out_ptr, &dec_out_ptr[ MAX_FS_KHZ * MAX_FRAME_LENGTH_MS ], MS_predictorIx, channel_state[ 0 ].fs_kHz, nSamplesOutDec );
}
/* Number of output samples */
if( doResample ) {
*nSamplesOut = SKP_DIV32( nSamplesOutDec * decControl->API_sampleRate, SKP_SMULBB( channel_state[ 0 ].fs_kHz, 1000 ) );
} else {
*nSamplesOut = nSamplesOutDec;
}
for( n = 0; n < decControl->nChannels; n++ ) {
/* Resample if needed */
if( doResample ) {
/* Initialize resampler when switching internal or external sampling frequency */
if( prev_fs_kHz != channel_state[ n ].fs_kHz || channel_state[ n ].prev_API_sampleRate != decControl->API_sampleRate ) {
ret = SKP_Silk_resampler_init( &channel_state[ n ].resampler_state, SKP_SMULBB( channel_state[ n ].fs_kHz, 1000 ), decControl->API_sampleRate );
}
/* Resample the output to API_sampleRate */
ret += SKP_Silk_resampler( &channel_state[ n ].resampler_state, resample_out_ptr, &dec_out_ptr[ n * MAX_FS_KHZ * MAX_FRAME_LENGTH_MS ], nSamplesOutDec );
} else {
resample_out_ptr = &dec_out_ptr[ n * MAX_FS_KHZ * MAX_FRAME_LENGTH_MS ];
}
/* Interleave if needed */
if( decControl->nChannels == 2 ) {
for( i = 0; i < *nSamplesOut; i++ ) {
samplesOut[ n + 2 * i ] = resample_out_ptr[ i ];
}
}
channel_state[ n ].prev_API_sampleRate = decControl->API_sampleRate;
}
/* Copy parameters to control stucture */
decControl->frameSize = ( SKP_int )*nSamplesOut;
decControl->framesPerPayload = ( SKP_int )channel_state[ n ].nFramesPerPacket;
return ret;
}
/* Getting table of contents for a packet */
SKP_int SKP_Silk_SDK_get_TOC(
const SKP_uint8 *payload, /* I Payload data */
const SKP_int nBytesIn, /* I: Number of input bytes */
const SKP_int nFramesPerPayload, /* I: Number of SILK frames per payload */
SKP_Silk_TOC_struct *Silk_TOC /* O: Type of content */
)
{
SKP_int i, flags, ret = SKP_SILK_NO_ERROR;
if( nBytesIn < 1 ) {
return -1;
}
if( nFramesPerPayload < 0 || nFramesPerPayload > 3 ) {
return -1;
}
SKP_memset( Silk_TOC, 0, sizeof( Silk_TOC ) );
/* For stereo, extract the flags for the mid channel */
flags = SKP_RSHIFT( payload[ 0 ], 7 - nFramesPerPayload ) & ( SKP_LSHIFT( 1, nFramesPerPayload + 1 ) - 1 );
Silk_TOC->inbandFECFlag = flags & 1;
for( i = nFramesPerPayload - 1; i >= 0 ; i-- ) {
flags = SKP_RSHIFT( flags, 1 );
Silk_TOC->VADFlags[ i ] = flags & 1;
Silk_TOC->VADFlag |= flags & 1;
}
return ret;
}