void SKP_Silk_detect_SWB_input(SKP_Silk_detect_SWB_state * psSWBdetect, /* (I/O) encoder state */
const int16_t samplesIn[], /* (I) input to encoder */
int nSamplesIn /* (I) length of input */
)
{
int HP_8_kHz_len, i;
int16_t in_HP_8_kHz[MAX_FRAME_LENGTH];
int32_t energy_32, shift;
/* High pass filter with cutoff at 8 khz */
HP_8_kHz_len = SKP_min_int(nSamplesIn, MAX_FRAME_LENGTH);
HP_8_kHz_len = SKP_max_int(HP_8_kHz_len, 0);
/* Cutoff around 9 khz */
/* A = conv(conv([8192,14613, 6868], [8192,12883, 7337]), [8192,11586, 7911]); */
/* B = conv(conv([575, -948, 575], [575, -221, 575]), [575, 104, 575]); */
SKP_Silk_biquad(samplesIn, SKP_Silk_SWB_detect_B_HP_Q13[0],
SKP_Silk_SWB_detect_A_HP_Q13[0],
psSWBdetect->S_HP_8_kHz[0], in_HP_8_kHz, HP_8_kHz_len);
for (i = 1; i < NB_SOS; i++) {
SKP_Silk_biquad(in_HP_8_kHz, SKP_Silk_SWB_detect_B_HP_Q13[i],
SKP_Silk_SWB_detect_A_HP_Q13[i],
psSWBdetect->S_HP_8_kHz[i], in_HP_8_kHz,
HP_8_kHz_len);
}
/* Calculate energy in HP signal */
SKP_Silk_sum_sqr_shift(&energy_32, &shift, in_HP_8_kHz, HP_8_kHz_len);
/* Count concecutive samples above threshold, after adjusting threshold for number of input samples and shift */
if (energy_32 >
SKP_RSHIFT(SKP_SMULBB(HP_8_KHZ_THRES, HP_8_kHz_len), shift)) {
psSWBdetect->ConsecSmplsAboveThres += nSamplesIn;
if (psSWBdetect->ConsecSmplsAboveThres > CONCEC_SWB_SMPLS_THRES) {
psSWBdetect->SWB_detected = 1;
}
} else {
psSWBdetect->ConsecSmplsAboveThres -= nSamplesIn;
psSWBdetect->ConsecSmplsAboveThres =
SKP_max(psSWBdetect->ConsecSmplsAboveThres, 0);
}
/* If sufficient speech activity and no SWB detected, we detect the signal as being WB */
if ((psSWBdetect->ActiveSpeech_ms > WB_DETECT_ACTIVE_SPEECH_MS_THRES)
&& (psSWBdetect->SWB_detected == 0)) {
psSWBdetect->WB_detected = 1;
}
}
SKP_int SKP_Silk_decode_frame(
SKP_Silk_decoder_state *psDec, /* I/O Pointer to Silk decoder state */
SKP_int16 pOut[], /* O Pointer to output speech frame */
SKP_int16 *pN, /* O Pointer to size of output frame */
const SKP_uint8 pCode[], /* I Pointer to payload */
const SKP_int nBytes, /* I Payload length */
SKP_int action, /* I Action from Jitter Buffer */
SKP_int *decBytes /* O Used bytes to decode this frame */
)
{
SKP_Silk_decoder_control sDecCtrl;
SKP_int L, fs_Khz_old, ret = 0;
SKP_int Pulses[ MAX_FRAME_LENGTH ];
L = psDec->frame_length;
sDecCtrl.LTP_scale_Q14 = 0;
/* Safety checks */
SKP_assert( L > 0 && L <= MAX_FRAME_LENGTH );
/********************************************/
/* Decode Frame if packet is not lost */
/********************************************/
*decBytes = 0;
if( action == 0 ) {
/********************************************/
/* Initialize arithmetic coder */
/********************************************/
fs_Khz_old = psDec->fs_kHz;
if( psDec->nFramesDecoded == 0 ) {
/* Initialize range decoder state */
SKP_Silk_range_dec_init( &psDec->sRC, pCode, nBytes );
}
/********************************************/
/* Decode parameters and pulse signal */
/********************************************/
SKP_Silk_decode_parameters( psDec, &sDecCtrl, Pulses, 1 );
if( psDec->sRC.error ) {
psDec->nBytesLeft = 0;
action = 1; /* PLC operation */
/* revert fs if changed in decode_parameters */
SKP_Silk_decoder_set_fs( psDec, fs_Khz_old );
/* Avoid crashing */
*decBytes = psDec->sRC.bufferLength;
if( psDec->sRC.error == RANGE_CODER_DEC_PAYLOAD_TOO_LONG ) {
ret = SKP_SILK_DEC_PAYLOAD_TOO_LARGE;
} else {
ret = SKP_SILK_DEC_PAYLOAD_ERROR;
}
} else {
*decBytes = psDec->sRC.bufferLength - psDec->nBytesLeft;
psDec->nFramesDecoded++;
/* Update lengths. Sampling frequency could have changed */
L = psDec->frame_length;
/********************************************************/
/* Run inverse NSQ */
/********************************************************/
SKP_Silk_decode_core( psDec, &sDecCtrl, pOut, Pulses );
/********************************************************/
/* Update PLC state */
/********************************************************/
SKP_Silk_PLC( psDec, &sDecCtrl, pOut, L, action );
psDec->lossCnt = 0;
psDec->prev_sigtype = sDecCtrl.sigtype;
/* A frame has been decoded without errors */
psDec->first_frame_after_reset = 0;
}
}
/*************************************************************/
/* Generate Concealment frame if packet is lost, or corrupt */
/*************************************************************/
if( action == 1 ) {
/* Handle packet loss by extrapolation */
SKP_Silk_PLC( psDec, &sDecCtrl, pOut, L, action );
}
/*************************/
/* Update output buffer. */
/*************************/
SKP_memcpy( psDec->outBuf, pOut, L * sizeof( SKP_int16 ) );
/****************************************************************/
/* Ensure smooth connection of extrapolated and good frames */
/****************************************************************/
SKP_Silk_PLC_glue_frames( psDec, &sDecCtrl, pOut, L );
/************************************************/
/* Comfort noise generation / estimation */
/************************************************/
SKP_Silk_CNG( psDec, &sDecCtrl, pOut , L );
/********************************************/
/* HP filter output */
/********************************************/
SKP_assert( ( ( psDec->fs_kHz == 12 ) && ( L % 3 ) == 0 ) ||
( ( psDec->fs_kHz != 12 ) && ( L % 2 ) == 0 ) );
SKP_Silk_biquad( pOut, psDec->HP_B, psDec->HP_A, psDec->HPState, pOut, L );
/********************************************/
/* set output frame length */
/********************************************/
*pN = ( SKP_int16 )L;
/* Update some decoder state variables */
psDec->lagPrev = sDecCtrl.pitchL[ NB_SUBFR - 1 ];
return ret;
}
