/* Resamples by a factor 3/2 */
void SKP_Silk_resample_3_2(int16_t * out, /* O: Fs_high signal [inLen*3/2] */
int32_t * S, /* I/O: State vector [7+4] */
const int16_t * in, /* I: Fs_low signal [inLen] */
int inLen /* I: Input length, must be a multiple of 2 */
)
{
int LSubFrameIn, LSubFrameOut;
int16_t outH[3 * IN_SUBFR_LEN_RESAMPLE_3_2];
int32_t scratch[(9 * IN_SUBFR_LEN_RESAMPLE_3_2) / 2];
/* Check that input is multiple of 2 */
assert(inLen % 2 == 0);
while (inLen > 0) {
LSubFrameIn = SKP_min_int(IN_SUBFR_LEN_RESAMPLE_3_2, inLen);
LSubFrameOut = SKP_SMULWB(98304, LSubFrameIn);
/* Upsample by a factor 3 */
SKP_Silk_resample_3_1(outH, &S[0], in, LSubFrameIn);
/* Downsample by a factor 2 */
/* Scratch size needs to be: 3 * LSubFrameOut * sizeof( int32_t ) */
SKP_Silk_resample_1_2_coarse(outH, &S[7], out, scratch,
LSubFrameOut);
in += LSubFrameIn;
out += LSubFrameOut;
inLen -= LSubFrameIn;
}
}
/* Resamples by a factor 3/4 */
void SKP_Silk_resample_3_4(int16_t * out, /* O: Fs_high signal [inLen*3/4] */
int32_t * S, /* I/O: State vector [7+2+6] */
const int16_t * in, /* I: Fs_low signal [inLen] */
int inLen /* I: Input length, must be a multiple of 4 */
)
{
int LSubFrameIn, LSubFrameOut;
int16_t outH[3 * IN_SUBFR_LEN_RESAMPLE_3_4];
int16_t outL[(3 * IN_SUBFR_LEN_RESAMPLE_3_4) / 2];
int32_t scratch[(9 * IN_SUBFR_LEN_RESAMPLE_3_4) / 2];
/* Check that input is multiple of 4 */
assert(inLen % 4 == 0);
while (inLen > 0) {
LSubFrameIn = SKP_min_int(IN_SUBFR_LEN_RESAMPLE_3_4, inLen);
LSubFrameOut = SKP_SMULWB(49152, LSubFrameIn);
/* Upsample by a factor 3 */
SKP_Silk_resample_3_1(outH, &S[0], in, LSubFrameIn);
/* Downsample by a factor 2 twice */
/* Scratch size needs to be: 3 * 2 * LSubFrameOut * sizeof( int32_t ) */
/* I: state vector [2], scratch memory [3*len] */
SKP_Silk_resample_1_2_coarsest(outH, &S[7], outL, scratch,
SKP_LSHIFT(LSubFrameOut, 1));
/* Scratch size needs to be: 3 * LSubFrameOut * sizeof( int32_t ) */
/* I: state vector [6], scratch memory [3*len] */
SKP_Silk_resample_1_2_coarse(outL, &S[9], out, scratch,
LSubFrameOut);
in += LSubFrameIn;
out += LSubFrameOut;
inLen -= LSubFrameIn;
}
}
/* Control encoder SNR */
SKP_int SKP_Silk_control_encoder_FIX(
SKP_Silk_encoder_state_FIX *psEnc, /* I/O Pointer to Silk encoder state */
const SKP_int API_fs_kHz, /* I External (API) sampling rate (kHz) */
const SKP_int PacketSize_ms, /* I Packet length (ms) */
SKP_int32 TargetRate_bps, /* I Target max bitrate (bps) (used if SNR_dB == 0) */
const SKP_int PacketLoss_perc, /* I Packet loss rate (in percent) */
const SKP_int INBandFec_enabled, /* I Enable (1) / disable (0) inband FEC */
const SKP_int DTX_enabled, /* I Enable / disable DTX */
const SKP_int InputFramesize_ms, /* I Inputframe in ms */
const SKP_int Complexity /* I Complexity (0->low; 1->medium; 2->high) */
)
{
SKP_int32 LBRRRate_thres_bps;
SKP_int k, fs_kHz, ret = 0;
SKP_int32 frac_Q6;
const SKP_int32 *rateTable;
/* State machine for the SWB/WB switching */
fs_kHz = psEnc->sCmn.fs_kHz;
/* Only switch during low speech activity, when no frames are sitting in the payload buffer */
if( API_fs_kHz == 8 || fs_kHz == 0 || API_fs_kHz < fs_kHz ) {
// Switching is not possible, encoder just initialized, or internal mode higher than external
fs_kHz = API_fs_kHz;
} else {
/* Resample all valid data in x_buf. Resampling the last part gets rid of a click, 5ms after switching */
/* this is because the same state is used when downsampling in API.c and is then up to date */
/* the click immidiatly after switching is most of the time still there */
if( psEnc->sCmn.fs_kHz == 24 ) {
/* Accumulate the difference between the target rate and limit */
if( psEnc->sCmn.fs_kHz_changed == 0 ) {
psEnc->sCmn.bitrateDiff += SKP_MUL( InputFramesize_ms, TargetRate_bps - SWB2WB_BITRATE_BPS_INITIAL );
} else {
psEnc->sCmn.bitrateDiff += SKP_MUL( InputFramesize_ms, TargetRate_bps - SWB2WB_BITRATE_BPS );
}
psEnc->sCmn.bitrateDiff = SKP_min( psEnc->sCmn.bitrateDiff, 0 );
/* Check if we should switch from 24 to 16 kHz */
#if SWITCH_TRANSITION_FILTERING
if( ( psEnc->sCmn.sLP.transition_frame_no == 0 ) && /* Transition phase not active */
( psEnc->sCmn.bitrateDiff <= -ACCUM_BITS_DIFF_THRESHOLD || psEnc->sCmn.sSWBdetect.WB_detected == 1 ) &&
( psEnc->speech_activity_Q8 < 128 && psEnc->sCmn.nFramesInPayloadBuf == 0 ) ) {
psEnc->sCmn.sLP.transition_frame_no = 1; /* Begin transition phase */
psEnc->sCmn.sLP.mode = 0; /* Switch down */
}
if( ( psEnc->sCmn.sLP.transition_frame_no >= TRANSITION_FRAMES_DOWN ) && ( psEnc->sCmn.sLP.mode == 0 ) && /* Transition phase complete, ready to switch */
#else
if( ( psEnc->sCmn.bitrateDiff <= -ACCUM_BITS_DIFF_THRESHOLD || psEnc->sCmn.sSWBdetect.WB_detected == 1 ) &&
#endif
( psEnc->speech_activity_Q8 < 128 && psEnc->sCmn.nFramesInPayloadBuf == 0 ) ) {
SKP_int16 x_buf[ 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ];
SKP_int16 x_bufout[ 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ];
psEnc->sCmn.bitrateDiff = 0;
fs_kHz = 16;
SKP_memcpy( x_buf, psEnc->x_buf, ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) * sizeof( SKP_int16 ) );
SKP_memset( psEnc->sCmn.resample24To16state, 0, sizeof( psEnc->sCmn.resample24To16state ) );
#if LOW_COMPLEXITY_ONLY
{
SKP_int16 scratch[ ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) + SigProc_Resample_2_3_coarse_NUM_FIR_COEFS - 1 ];
SKP_Silk_resample_2_3_coarse( &x_bufout[ 0 ], psEnc->sCmn.resample24To16state, &x_buf[ 0 ], SKP_LSHIFT( psEnc->sCmn.frame_length, 1 ) + psEnc->sCmn.la_shape, (SKP_int16*)scratch );
}
#else
SKP_Silk_resample_2_3( &x_bufout[ 0 ], psEnc->sCmn.resample24To16state, &x_buf[ 0 ], SKP_LSHIFT( psEnc->sCmn.frame_length, 1 ) + psEnc->sCmn.la_shape );
#endif
/* set the first frame to zero, no performance difference was noticed though */
SKP_memset( x_bufout, 0, 320 * sizeof( SKP_int16 ) );
SKP_memcpy( psEnc->x_buf, x_bufout, ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) * sizeof( SKP_int16 ) );
#if SWITCH_TRANSITION_FILTERING
psEnc->sCmn.sLP.transition_frame_no = 0; /* Transition phase complete */
#endif
}
} else if( psEnc->sCmn.fs_kHz == 16 ) {
/* Check if we should switch from 16 to 24 kHz */
#if SWITCH_TRANSITION_FILTERING
if( ( psEnc->sCmn.sLP.transition_frame_no == 0 ) && /* No transition phase running, ready to switch */
#else
if(
#endif
( API_fs_kHz > psEnc->sCmn.fs_kHz && TargetRate_bps >= WB2SWB_BITRATE_BPS && psEnc->sCmn.sSWBdetect.WB_detected == 0 ) &&
( psEnc->speech_activity_Q8 < 128 && psEnc->sCmn.nFramesInPayloadBuf == 0 ) ) {
SKP_int16 x_buf[ 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ];
SKP_int16 x_bufout[ 3 * ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) / 2 ];
SKP_int32 resample16To24state[ 11 ];
psEnc->sCmn.bitrateDiff = 0;
fs_kHz = 24;
SKP_memcpy( x_buf, psEnc->x_buf, ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) * sizeof( SKP_int16 ) );
SKP_memset( resample16To24state, 0, sizeof(resample16To24state) );
SKP_Silk_resample_3_2( &x_bufout[ 0 ], resample16To24state, &x_buf[ 0 ], SKP_LSHIFT( psEnc->sCmn.frame_length, 1 ) + psEnc->sCmn.la_shape );
/* set the first frame to zero, no performance difference was noticed though */
SKP_memset( x_bufout, 0, 480 * sizeof( SKP_int16 ) );
SKP_memcpy( psEnc->x_buf, x_bufout, ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) * sizeof( SKP_int16 ) );
#if SWITCH_TRANSITION_FILTERING
psEnc->sCmn.sLP.mode = 1; /* Switch up */
#endif
} else {
/* accumulate the difference between the target rate and limit */
psEnc->sCmn.bitrateDiff += SKP_MUL( InputFramesize_ms, TargetRate_bps - WB2MB_BITRATE_BPS );
psEnc->sCmn.bitrateDiff = SKP_min( psEnc->sCmn.bitrateDiff, 0 );
/* Check if we should switch from 16 to 12 kHz */
#if SWITCH_TRANSITION_FILTERING
if( ( psEnc->sCmn.sLP.transition_frame_no == 0 ) && /* Transition phase not active */
( psEnc->sCmn.bitrateDiff <= -ACCUM_BITS_DIFF_THRESHOLD ) &&
( psEnc->speech_activity_Q8 < 128 && psEnc->sCmn.nFramesInPayloadBuf == 0 ) ) {
psEnc->sCmn.sLP.transition_frame_no = 1; /* Begin transition phase */
psEnc->sCmn.sLP.mode = 0; /* Switch down */
}
if( ( psEnc->sCmn.sLP.transition_frame_no >= TRANSITION_FRAMES_DOWN ) && ( psEnc->sCmn.sLP.mode == 0 ) && /* Transition phase complete, ready to switch */
#else
if( ( psEnc->sCmn.bitrateDiff <= -ACCUM_BITS_DIFF_THRESHOLD ) &&
#endif
( psEnc->speech_activity_Q8 < 128 && psEnc->sCmn.nFramesInPayloadBuf == 0 ) ) {
SKP_int16 x_buf[ 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ];
SKP_memcpy( x_buf, psEnc->x_buf, ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) * sizeof( SKP_int16 ) );
psEnc->sCmn.bitrateDiff = 0;
fs_kHz = 12;
if( API_fs_kHz == 24 ) {
/* Intermediate upsampling of x_bufFIX from 16 to 24 kHz */
SKP_int16 x_buf24[ 3 * ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) / 2 ];
SKP_int32 scratch[ 3 * ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) ];
SKP_int32 resample16To24state[ 11 ];
SKP_memset( resample16To24state, 0, sizeof( resample16To24state ) );
SKP_Silk_resample_3_2( &x_buf24[ 0 ], resample16To24state, &x_buf[ 0 ], SKP_LSHIFT( psEnc->sCmn.frame_length, 1 ) + psEnc->sCmn.la_shape );
/* Update the state of the resampler used in API.c, from 24 to 12 kHz */
SKP_memset( psEnc->sCmn.resample24To12state, 0, sizeof( psEnc->sCmn.resample24To12state ) );
SKP_Silk_resample_1_2_coarse( &x_buf24[ 0 ], psEnc->sCmn.resample24To12state, &x_buf[ 0 ], scratch, SKP_RSHIFT( SKP_SMULBB( 3, SKP_LSHIFT( psEnc->sCmn.frame_length, 1 ) + psEnc->sCmn.la_shape ), 2 ) );
/* set the first frame to zero, no performance difference was noticed though */
SKP_memset( x_buf, 0, 240 * sizeof( SKP_int16 ) );
SKP_memcpy( psEnc->x_buf, x_buf, ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) * sizeof( SKP_int16 ) );
} else if( API_fs_kHz == 16 ) {
SKP_int16 x_bufout[ 3 * ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) / 4 ];
SKP_memset( psEnc->sCmn.resample16To12state, 0, sizeof( psEnc->sCmn.resample16To12state ) );
SKP_Silk_resample_3_4( &x_bufout[ 0 ], psEnc->sCmn.resample16To12state, &x_buf[ 0 ], SKP_LSHIFT( psEnc->sCmn.frame_length, 1 ) + psEnc->sCmn.la_shape );
/* set the first frame to zero, no performance difference was noticed though */
SKP_memset( x_bufout, 0, 240 * sizeof( SKP_int16 ) );
SKP_memcpy( psEnc->x_buf, x_bufout, ( 2 * MAX_FRAME_LENGTH + LA_SHAPE_MAX ) * sizeof( SKP_int16 ) );
}
#if SWITCH_TRANSITION_FILTERING
psEnc->sCmn.sLP.transition_frame_no = 0; /* Transition phase complete */
#endif
}
}
} else if( psEnc->sCmn.fs_kHz == 12 ) {
