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Diffstat (limited to 'src/opus-1.0.2/silk/fixed/find_LTP_FIX.c')
| -rw-r--r-- | src/opus-1.0.2/silk/fixed/find_LTP_FIX.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/src/opus-1.0.2/silk/fixed/find_LTP_FIX.c b/src/opus-1.0.2/silk/fixed/find_LTP_FIX.c new file mode 100644 index 00000000..bd210874 --- /dev/null +++ b/src/opus-1.0.2/silk/fixed/find_LTP_FIX.c @@ -0,0 +1,244 @@ +/*********************************************************************** +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_FIX.h" +#include "tuning_parameters.h" + +/* Head room for correlations */ +#define LTP_CORRS_HEAD_ROOM 2 + +void silk_fit_LTP( + opus_int32 LTP_coefs_Q16[ LTP_ORDER ], + opus_int16 LTP_coefs_Q14[ LTP_ORDER ] +); + +void silk_find_LTP_FIX( + opus_int16 b_Q14[ MAX_NB_SUBFR * LTP_ORDER ], /* O LTP coefs */ + opus_int32 WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ], /* O Weight for LTP quantization */ + opus_int *LTPredCodGain_Q7, /* O LTP coding gain */ + const opus_int16 r_lpc[], /* I residual signal after LPC signal + state for first 10 ms */ + const opus_int lag[ MAX_NB_SUBFR ], /* I LTP lags */ + const opus_int32 Wght_Q15[ MAX_NB_SUBFR ], /* I weights */ + const opus_int subfr_length, /* I subframe length */ + const opus_int nb_subfr, /* I number of subframes */ + const opus_int mem_offset, /* I number of samples in LTP memory */ + opus_int corr_rshifts[ MAX_NB_SUBFR ] /* O right shifts applied to correlations */ +) +{ + opus_int i, k, lshift; + const opus_int16 *r_ptr, *lag_ptr; + opus_int16 *b_Q14_ptr; + + opus_int32 regu; + opus_int32 *WLTP_ptr; + opus_int32 b_Q16[ LTP_ORDER ], delta_b_Q14[ LTP_ORDER ], d_Q14[ MAX_NB_SUBFR ], nrg[ MAX_NB_SUBFR ], g_Q26; + opus_int32 w[ MAX_NB_SUBFR ], WLTP_max, max_abs_d_Q14, max_w_bits; + + opus_int32 temp32, denom32; + opus_int extra_shifts; + opus_int rr_shifts, maxRshifts, maxRshifts_wxtra, LZs; + opus_int32 LPC_res_nrg, LPC_LTP_res_nrg, div_Q16; + opus_int32 Rr[ LTP_ORDER ], rr[ MAX_NB_SUBFR ]; + opus_int32 wd, m_Q12; + + b_Q14_ptr = b_Q14; + WLTP_ptr = WLTP; + r_ptr = &r_lpc[ mem_offset ]; + for( k = 0; k < nb_subfr; k++ ) { + lag_ptr = r_ptr - ( lag[ k ] + LTP_ORDER / 2 ); + + silk_sum_sqr_shift( &rr[ k ], &rr_shifts, r_ptr, subfr_length ); /* rr[ k ] in Q( -rr_shifts ) */ + + /* Assure headroom */ + LZs = silk_CLZ32( rr[k] ); + if( LZs < LTP_CORRS_HEAD_ROOM ) { + rr[ k ] = silk_RSHIFT_ROUND( rr[ k ], LTP_CORRS_HEAD_ROOM - LZs ); + rr_shifts += ( LTP_CORRS_HEAD_ROOM - LZs ); + } + corr_rshifts[ k ] = rr_shifts; + silk_corrMatrix_FIX( lag_ptr, subfr_length, LTP_ORDER, LTP_CORRS_HEAD_ROOM, WLTP_ptr, &corr_rshifts[ k ] ); /* WLTP_fix_ptr in Q( -corr_rshifts[ k ] ) */ + + /* The correlation vector always has lower max abs value than rr and/or RR so head room is assured */ + silk_corrVector_FIX( lag_ptr, r_ptr, subfr_length, LTP_ORDER, Rr, corr_rshifts[ k ] ); /* Rr_fix_ptr in Q( -corr_rshifts[ k ] ) */ + if( corr_rshifts[ k ] > rr_shifts ) { + rr[ k ] = silk_RSHIFT( rr[ k ], corr_rshifts[ k ] - rr_shifts ); /* rr[ k ] in Q( -corr_rshifts[ k ] ) */ + } + silk_assert( rr[ k ] >= 0 ); + + regu = 1; + regu = silk_SMLAWB( regu, rr[ k ], SILK_FIX_CONST( LTP_DAMPING/3, 16 ) ); + regu = silk_SMLAWB( regu, matrix_ptr( WLTP_ptr, 0, 0, LTP_ORDER ), SILK_FIX_CONST( LTP_DAMPING/3, 16 ) ); + regu = silk_SMLAWB( regu, matrix_ptr( WLTP_ptr, LTP_ORDER-1, LTP_ORDER-1, LTP_ORDER ), SILK_FIX_CONST( LTP_DAMPING/3, 16 ) ); + silk_regularize_correlations_FIX( WLTP_ptr, &rr[k], regu, LTP_ORDER ); + + silk_solve_LDL_FIX( WLTP_ptr, LTP_ORDER, Rr, b_Q16 ); /* WLTP_fix_ptr and Rr_fix_ptr both in Q(-corr_rshifts[k]) */ + + /* Limit and store in Q14 */ + silk_fit_LTP( b_Q16, b_Q14_ptr ); + + /* Calculate residual energy */ + nrg[ k ] = silk_residual_energy16_covar_FIX( b_Q14_ptr, WLTP_ptr, Rr, rr[ k ], LTP_ORDER, 14 ); /* nrg_fix in Q( -corr_rshifts[ k ] ) */ + + /* temp = Wght[ k ] / ( nrg[ k ] * Wght[ k ] + 0.01f * subfr_length ); */ + extra_shifts = silk_min_int( corr_rshifts[ k ], LTP_CORRS_HEAD_ROOM ); + denom32 = silk_LSHIFT_SAT32( silk_SMULWB( nrg[ k ], Wght_Q15[ k ] ), 1 + extra_shifts ) + /* Q( -corr_rshifts[ k ] + extra_shifts ) */ + silk_RSHIFT( silk_SMULWB( (opus_int32)subfr_length, 655 ), corr_rshifts[ k ] - extra_shifts ); /* Q( -corr_rshifts[ k ] + extra_shifts ) */ + denom32 = silk_max( denom32, 1 ); + silk_assert( ((opus_int64)Wght_Q15[ k ] << 16 ) < silk_int32_MAX ); /* Wght always < 0.5 in Q0 */ + temp32 = silk_DIV32( silk_LSHIFT( (opus_int32)Wght_Q15[ k ], 16 ), denom32 ); /* Q( 15 + 16 + corr_rshifts[k] - extra_shifts ) */ + temp32 = silk_RSHIFT( temp32, 31 + corr_rshifts[ k ] - extra_shifts - 26 ); /* Q26 */ + + /* Limit temp such that the below scaling never wraps around */ + WLTP_max = 0; + for( i = 0; i < LTP_ORDER * LTP_ORDER; i++ ) { + WLTP_max = silk_max( WLTP_ptr[ i ], WLTP_max ); + } + lshift = silk_CLZ32( WLTP_max ) - 1 - 3; /* keep 3 bits free for vq_nearest_neighbor_fix */ + silk_assert( 26 - 18 + lshift >= 0 ); + if( 26 - 18 + lshift < 31 ) { + temp32 = silk_min_32( temp32, silk_LSHIFT( (opus_int32)1, 26 - 18 + lshift ) ); + } + + silk_scale_vector32_Q26_lshift_18( WLTP_ptr, temp32, LTP_ORDER * LTP_ORDER ); /* WLTP_ptr in Q( 18 - corr_rshifts[ k ] ) */ + + w[ k ] = matrix_ptr( WLTP_ptr, LTP_ORDER/2, LTP_ORDER/2, LTP_ORDER ); /* w in Q( 18 - corr_rshifts[ k ] ) */ + silk_assert( w[k] >= 0 ); + + r_ptr += subfr_length; + b_Q14_ptr += LTP_ORDER; + WLTP_ptr += LTP_ORDER * LTP_ORDER; + } + + maxRshifts = 0; + for( k = 0; k < nb_subfr; k++ ) { + maxRshifts = silk_max_int( corr_rshifts[ k ], maxRshifts ); + } + + /* Compute LTP coding gain */ + if( LTPredCodGain_Q7 != NULL ) { + LPC_LTP_res_nrg = 0; + LPC_res_nrg = 0; + silk_assert( LTP_CORRS_HEAD_ROOM >= 2 ); /* Check that no overflow will happen when adding */ + for( k = 0; k < nb_subfr; k++ ) { + LPC_res_nrg = silk_ADD32( LPC_res_nrg, silk_RSHIFT( silk_ADD32( silk_SMULWB( rr[ k ], Wght_Q15[ k ] ), 1 ), 1 + ( maxRshifts - corr_rshifts[ k ] ) ) ); /* Q( -maxRshifts ) */ + LPC_LTP_res_nrg = silk_ADD32( LPC_LTP_res_nrg, silk_RSHIFT( silk_ADD32( silk_SMULWB( nrg[ k ], Wght_Q15[ k ] ), 1 ), 1 + ( maxRshifts - corr_rshifts[ k ] ) ) ); /* Q( -maxRshifts ) */ + } + LPC_LTP_res_nrg = silk_max( LPC_LTP_res_nrg, 1 ); /* avoid division by zero */ + + div_Q16 = silk_DIV32_varQ( LPC_res_nrg, LPC_LTP_res_nrg, 16 ); + *LTPredCodGain_Q7 = ( opus_int )silk_SMULBB( 3, silk_lin2log( div_Q16 ) - ( 16 << 7 ) ); + + silk_assert( *LTPredCodGain_Q7 == ( opus_int )silk_SAT16( silk_MUL( 3, silk_lin2log( div_Q16 ) - ( 16 << 7 ) ) ) ); + } + + /* smoothing */ + /* d = sum( B, 1 ); */ + b_Q14_ptr = b_Q14; + for( k = 0; k < nb_subfr; k++ ) { + d_Q14[ k ] = 0; + for( i = 0; i < LTP_ORDER; i++ ) { + d_Q14[ k ] += b_Q14_ptr[ i ]; + } + b_Q14_ptr += LTP_ORDER; + } + + /* m = ( w * d' ) / ( sum( w ) + 1e-3 ); */ + + /* Find maximum absolute value of d_Q14 and the bits used by w in Q0 */ + max_abs_d_Q14 = 0; + max_w_bits = 0; + for( k = 0; k < nb_subfr; k++ ) { + max_abs_d_Q14 = silk_max_32( max_abs_d_Q14, silk_abs( d_Q14[ k ] ) ); + /* w[ k ] is in Q( 18 - corr_rshifts[ k ] ) */ + /* Find bits needed in Q( 18 - maxRshifts ) */ + max_w_bits = silk_max_32( max_w_bits, 32 - silk_CLZ32( w[ k ] ) + corr_rshifts[ k ] - maxRshifts ); + } + + /* max_abs_d_Q14 = (5 << 15); worst case, i.e. LTP_ORDER * -silk_int16_MIN */ + silk_assert( max_abs_d_Q14 <= ( 5 << 15 ) ); + + /* How many bits is needed for w*d' in Q( 18 - maxRshifts ) in the worst case, of all d_Q14's being equal to max_abs_d_Q14 */ + extra_shifts = max_w_bits + 32 - silk_CLZ32( max_abs_d_Q14 ) - 14; + + /* Subtract what we got available; bits in output var plus maxRshifts */ + extra_shifts -= ( 32 - 1 - 2 + maxRshifts ); /* Keep sign bit free as well as 2 bits for accumulation */ + extra_shifts = silk_max_int( extra_shifts, 0 ); + + maxRshifts_wxtra = maxRshifts + extra_shifts; + + temp32 = silk_RSHIFT( 262, maxRshifts + extra_shifts ) + 1; /* 1e-3f in Q( 18 - (maxRshifts + extra_shifts) ) */ + wd = 0; + for( k = 0; k < nb_subfr; k++ ) { + /* w has at least 2 bits of headroom so no overflow should happen */ + temp32 = silk_ADD32( temp32, silk_RSHIFT( w[ k ], maxRshifts_wxtra - corr_rshifts[ k ] ) ); /* Q( 18 - maxRshifts_wxtra ) */ + wd = silk_ADD32( wd, silk_LSHIFT( silk_SMULWW( silk_RSHIFT( w[ k ], maxRshifts_wxtra - corr_rshifts[ k ] ), d_Q14[ k ] ), 2 ) ); /* Q( 18 - maxRshifts_wxtra ) */ + } + m_Q12 = silk_DIV32_varQ( wd, temp32, 12 ); + + b_Q14_ptr = b_Q14; + for( k = 0; k < nb_subfr; k++ ) { + /* w_fix[ k ] from Q( 18 - corr_rshifts[ k ] ) to Q( 16 ) */ + if( 2 - corr_rshifts[k] > 0 ) { + temp32 = silk_RSHIFT( w[ k ], 2 - corr_rshifts[ k ] ); + } else { + temp32 = silk_LSHIFT_SAT32( w[ k ], corr_rshifts[ k ] - 2 ); + } + + g_Q26 = silk_MUL( + silk_DIV32( + SILK_FIX_CONST( LTP_SMOOTHING, 26 ), + silk_RSHIFT( SILK_FIX_CONST( LTP_SMOOTHING, 26 ), 10 ) + temp32 ), /* Q10 */ + silk_LSHIFT_SAT32( silk_SUB_SAT32( (opus_int32)m_Q12, silk_RSHIFT( d_Q14[ k ], 2 ) ), 4 ) ); /* Q16 */ + + temp32 = 0; + for( i = 0; i < LTP_ORDER; i++ ) { + delta_b_Q14[ i ] = silk_max_16( b_Q14_ptr[ i ], 1638 ); /* 1638_Q14 = 0.1_Q0 */ + temp32 += delta_b_Q14[ i ]; /* Q14 */ + } + temp32 = silk_DIV32( g_Q26, temp32 ); /* Q14 -> Q12 */ + for( i = 0; i < LTP_ORDER; i++ ) { + b_Q14_ptr[ i ] = silk_LIMIT_32( (opus_int32)b_Q14_ptr[ i ] + silk_SMULWB( silk_LSHIFT_SAT32( temp32, 4 ), delta_b_Q14[ i ] ), -16000, 28000 ); + } + b_Q14_ptr += LTP_ORDER; + } +} + +void silk_fit_LTP( + opus_int32 LTP_coefs_Q16[ LTP_ORDER ], + opus_int16 LTP_coefs_Q14[ LTP_ORDER ] +) +{ + opus_int i; + + for( i = 0; i < LTP_ORDER; i++ ) { + LTP_coefs_Q14[ i ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( LTP_coefs_Q16[ i ], 2 ) ); + } +} |