summaryrefslogtreecommitdiffstats
path: root/media/libopus/silk/CNG.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--media/libopus/silk/CNG.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/media/libopus/silk/CNG.c b/media/libopus/silk/CNG.c
new file mode 100644
index 0000000000..2a910099ed
--- /dev/null
+++ b/media/libopus/silk/CNG.c
@@ -0,0 +1,188 @@
+/***********************************************************************
+Copyright (c) 2006-2011, Skype Limited. All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+- Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+- Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.
+- Neither the name of Internet Society, IETF or IETF Trust, nor the
+names of specific contributors, may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+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
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+***********************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "main.h"
+#include "stack_alloc.h"
+
+/* Generates excitation for CNG LPC synthesis */
+static OPUS_INLINE void silk_CNG_exc(
+ opus_int32 exc_Q14[], /* O CNG excitation signal Q10 */
+ opus_int32 exc_buf_Q14[], /* I Random samples buffer Q10 */
+ opus_int length, /* I Length */
+ opus_int32 *rand_seed /* I/O Seed to random index generator */
+)
+{
+ opus_int32 seed;
+ opus_int i, idx, exc_mask;
+
+ exc_mask = CNG_BUF_MASK_MAX;
+ while( exc_mask > length ) {
+ exc_mask = silk_RSHIFT( exc_mask, 1 );
+ }
+
+ seed = *rand_seed;
+ for( i = 0; i < length; i++ ) {
+ seed = silk_RAND( seed );
+ idx = (opus_int)( silk_RSHIFT( seed, 24 ) & exc_mask );
+ silk_assert( idx >= 0 );
+ silk_assert( idx <= CNG_BUF_MASK_MAX );
+ exc_Q14[ i ] = exc_buf_Q14[ idx ];
+ }
+ *rand_seed = seed;
+}
+
+void silk_CNG_Reset(
+ silk_decoder_state *psDec /* I/O Decoder state */
+)
+{
+ opus_int i, NLSF_step_Q15, NLSF_acc_Q15;
+
+ NLSF_step_Q15 = silk_DIV32_16( silk_int16_MAX, psDec->LPC_order + 1 );
+ NLSF_acc_Q15 = 0;
+ for( i = 0; i < psDec->LPC_order; i++ ) {
+ NLSF_acc_Q15 += NLSF_step_Q15;
+ psDec->sCNG.CNG_smth_NLSF_Q15[ i ] = NLSF_acc_Q15;
+ }
+ psDec->sCNG.CNG_smth_Gain_Q16 = 0;
+ psDec->sCNG.rand_seed = 3176576;
+}
+
+/* Updates CNG estimate, and applies the CNG when packet was lost */
+void silk_CNG(
+ silk_decoder_state *psDec, /* I/O Decoder state */
+ silk_decoder_control *psDecCtrl, /* I/O Decoder control */
+ opus_int16 frame[], /* I/O Signal */
+ opus_int length /* I Length of residual */
+)
+{
+ opus_int i, subfr;
+ opus_int32 LPC_pred_Q10, max_Gain_Q16, gain_Q16, gain_Q10;
+ opus_int16 A_Q12[ MAX_LPC_ORDER ];
+ silk_CNG_struct *psCNG = &psDec->sCNG;
+ SAVE_STACK;
+
+ if( psDec->fs_kHz != psCNG->fs_kHz ) {
+ /* Reset state */
+ silk_CNG_Reset( psDec );
+
+ psCNG->fs_kHz = psDec->fs_kHz;
+ }
+ if( psDec->lossCnt == 0 && psDec->prevSignalType == TYPE_NO_VOICE_ACTIVITY ) {
+ /* Update CNG parameters */
+
+ /* Smoothing of LSF's */
+ for( i = 0; i < psDec->LPC_order; i++ ) {
+ psCNG->CNG_smth_NLSF_Q15[ i ] += silk_SMULWB( (opus_int32)psDec->prevNLSF_Q15[ i ] - (opus_int32)psCNG->CNG_smth_NLSF_Q15[ i ], CNG_NLSF_SMTH_Q16 );
+ }
+ /* Find the subframe with the highest gain */
+ max_Gain_Q16 = 0;
+ subfr = 0;
+ for( i = 0; i < psDec->nb_subfr; i++ ) {
+ if( psDecCtrl->Gains_Q16[ i ] > max_Gain_Q16 ) {
+ max_Gain_Q16 = psDecCtrl->Gains_Q16[ i ];
+ subfr = i;
+ }
+ }
+ /* Update CNG excitation buffer with excitation from this subframe */
+ silk_memmove( &psCNG->CNG_exc_buf_Q14[ psDec->subfr_length ], psCNG->CNG_exc_buf_Q14, ( psDec->nb_subfr - 1 ) * psDec->subfr_length * sizeof( opus_int32 ) );
+ silk_memcpy( psCNG->CNG_exc_buf_Q14, &psDec->exc_Q14[ subfr * psDec->subfr_length ], psDec->subfr_length * sizeof( opus_int32 ) );
+
+ /* Smooth gains */
+ for( i = 0; i < psDec->nb_subfr; i++ ) {
+ psCNG->CNG_smth_Gain_Q16 += silk_SMULWB( psDecCtrl->Gains_Q16[ i ] - psCNG->CNG_smth_Gain_Q16, CNG_GAIN_SMTH_Q16 );
+ /* If the smoothed gain is 3 dB greater than this subframe's gain, use this subframe's gain to adapt faster. */
+ if( silk_SMULWW( psCNG->CNG_smth_Gain_Q16, CNG_GAIN_SMTH_THRESHOLD_Q16 ) > psDecCtrl->Gains_Q16[ i ] ) {
+ psCNG->CNG_smth_Gain_Q16 = psDecCtrl->Gains_Q16[ i ];
+ }
+ }
+ }
+
+ /* Add CNG when packet is lost or during DTX */
+ if( psDec->lossCnt ) {
+ VARDECL( opus_int32, CNG_sig_Q14 );
+ ALLOC( CNG_sig_Q14, length + MAX_LPC_ORDER, opus_int32 );
+
+ /* Generate CNG excitation */
+ gain_Q16 = silk_SMULWW( psDec->sPLC.randScale_Q14, psDec->sPLC.prevGain_Q16[1] );
+ if( gain_Q16 >= (1 << 21) || psCNG->CNG_smth_Gain_Q16 > (1 << 23) ) {
+ gain_Q16 = silk_SMULTT( gain_Q16, gain_Q16 );
+ gain_Q16 = silk_SUB_LSHIFT32(silk_SMULTT( psCNG->CNG_smth_Gain_Q16, psCNG->CNG_smth_Gain_Q16 ), gain_Q16, 5 );
+ gain_Q16 = silk_LSHIFT32( silk_SQRT_APPROX( gain_Q16 ), 16 );
+ } else {
+ gain_Q16 = silk_SMULWW( gain_Q16, gain_Q16 );
+ gain_Q16 = silk_SUB_LSHIFT32(silk_SMULWW( psCNG->CNG_smth_Gain_Q16, psCNG->CNG_smth_Gain_Q16 ), gain_Q16, 5 );
+ gain_Q16 = silk_LSHIFT32( silk_SQRT_APPROX( gain_Q16 ), 8 );
+ }
+ gain_Q10 = silk_RSHIFT( gain_Q16, 6 );
+
+ silk_CNG_exc( CNG_sig_Q14 + MAX_LPC_ORDER, psCNG->CNG_exc_buf_Q14, length, &psCNG->rand_seed );
+
+ /* Convert CNG NLSF to filter representation */
+ silk_NLSF2A( A_Q12, psCNG->CNG_smth_NLSF_Q15, psDec->LPC_order, psDec->arch );
+
+ /* Generate CNG signal, by synthesis filtering */
+ silk_memcpy( CNG_sig_Q14, psCNG->CNG_synth_state, MAX_LPC_ORDER * sizeof( opus_int32 ) );
+ celt_assert( psDec->LPC_order == 10 || psDec->LPC_order == 16 );
+ for( i = 0; i < length; i++ ) {
+ /* Avoids introducing a bias because silk_SMLAWB() always rounds to -inf */
+ LPC_pred_Q10 = silk_RSHIFT( psDec->LPC_order, 1 );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 1 ], A_Q12[ 0 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 2 ], A_Q12[ 1 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 3 ], A_Q12[ 2 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 4 ], A_Q12[ 3 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 5 ], A_Q12[ 4 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 6 ], A_Q12[ 5 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 7 ], A_Q12[ 6 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 8 ], A_Q12[ 7 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 9 ], A_Q12[ 8 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 10 ], A_Q12[ 9 ] );
+ if( psDec->LPC_order == 16 ) {
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 11 ], A_Q12[ 10 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 12 ], A_Q12[ 11 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 13 ], A_Q12[ 12 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 14 ], A_Q12[ 13 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 15 ], A_Q12[ 14 ] );
+ LPC_pred_Q10 = silk_SMLAWB( LPC_pred_Q10, CNG_sig_Q14[ MAX_LPC_ORDER + i - 16 ], A_Q12[ 15 ] );
+ }
+
+ /* Update states */
+ CNG_sig_Q14[ MAX_LPC_ORDER + i ] = silk_ADD_SAT32( CNG_sig_Q14[ MAX_LPC_ORDER + i ], silk_LSHIFT_SAT32( LPC_pred_Q10, 4 ) );
+
+ /* Scale with Gain and add to input signal */
+ frame[ i ] = (opus_int16)silk_ADD_SAT16( frame[ i ], silk_SAT16( silk_RSHIFT_ROUND( silk_SMULWW( CNG_sig_Q14[ MAX_LPC_ORDER + i ], gain_Q10 ), 8 ) ) );
+
+ }
+ silk_memcpy( psCNG->CNG_synth_state, &CNG_sig_Q14[ length ], MAX_LPC_ORDER * sizeof( opus_int32 ) );
+ } else {
+ silk_memset( psCNG->CNG_synth_state, 0, psDec->LPC_order * sizeof( opus_int32 ) );
+ }
+ RESTORE_STACK;
+}