/* Decodes signs of excitation */
void SKP_Silk_decode_signs(SKP_Silk_range_coder_state * sRC, /* I/O Range coder state */
int q[], /* I/O pulse signal */
const int length, /* I length of output */
const int sigtype, /* I Signal type */
const int QuantOffsetType, /* I Quantization offset type */
const int RateLevelIndex /* I Rate Level Index */
)
{
int i;
int data;
const uint16_t *cdf;
i = SKP_SMULBB(N_RATE_LEVELS - 1,
SKP_LSHIFT(sigtype,
1) + QuantOffsetType) + RateLevelIndex;
cdf = SKP_Silk_sign_CDF[i];
for (i = 0; i < length; i++) {
if (q[i] > 0) {
SKP_Silk_range_decoder(&data, sRC, cdf, 1);
/* attach sign */
/* implementation with shift, subtraction, multiplication */
q[i] *= SKP_dec_map(data);
}
}
}
/* Decodes signs of excitation */
void silk_decode_signs(
ec_dec *psRangeDec, /* I/O Compressor data structure */
SKP_int pulses[], /* I/O pulse signal */
SKP_int length, /* I length of input */
const SKP_int signalType, /* I Signal type */
const SKP_int quantOffsetType, /* I Quantization offset type */
const SKP_int sum_pulses[ MAX_NB_SHELL_BLOCKS ] /* I Sum of absolute pulses per block */
)
{
SKP_int i, j, p;
SKP_uint8 icdf[ 2 ];
SKP_int *q_ptr;
const SKP_uint8 *icdf_ptr;
icdf[ 1 ] = 0;
q_ptr = pulses;
i = SKP_SMULBB( 6, SKP_ADD_LSHIFT( quantOffsetType, signalType, 1 ) );
icdf_ptr = &silk_sign_iCDF[ i ];
length = SKP_RSHIFT( length + SHELL_CODEC_FRAME_LENGTH/2, LOG2_SHELL_CODEC_FRAME_LENGTH );
for( i = 0; i < length; i++ ) {
p = sum_pulses[ i ];
if( p > 0 ) {
icdf[ 0 ] = icdf_ptr[ SKP_min( p - 1, 5 ) ];
for( j = 0; j < SHELL_CODEC_FRAME_LENGTH; j++ ) {
if( q_ptr[ j ] > 0 ) {
/* attach sign */
#if 0
/* conditional implementation */
if( ec_dec_icdf( psRangeDec, icdf, 8 ) == 0 ) {
q_ptr[ j ] = -q_ptr[ j ];
}
#else
/* implementation with shift, subtraction, multiplication */
q_ptr[ j ] *= SKP_dec_map( ec_dec_icdf( psRangeDec, icdf, 8 ) );
#endif
}
}
}
q_ptr += SHELL_CODEC_FRAME_LENGTH;
}
}
