diff options
Diffstat (limited to 'src_FIX/SKP_Silk_find_LTP_FIX.c')
| -rw-r--r-- | src_FIX/SKP_Silk_find_LTP_FIX.c | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/src_FIX/SKP_Silk_find_LTP_FIX.c b/src_FIX/SKP_Silk_find_LTP_FIX.c index 2f0881e9..cddc29a4 100644 --- a/src_FIX/SKP_Silk_find_LTP_FIX.c +++ b/src_FIX/SKP_Silk_find_LTP_FIX.c @@ -26,6 +26,10 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. ***********************************************************************/
#include "SKP_Silk_main_FIX.h"
+#include "SKP_Silk_tuning_parameters.h"
+
+/* Head room for correlations */
+#define LTP_CORRS_HEAD_ROOM 2
void SKP_Silk_fit_LTP(
SKP_int32 LTP_coefs_Q16[ LTP_ORDER ],
@@ -68,22 +72,24 @@ void SKP_Silk_find_LTP_FIX( lag_ptr = r_ptr - ( lag[ k ] + LTP_ORDER / 2 );
SKP_Silk_sum_sqr_shift( &rr[ k ], &rr_shifts, r_ptr, subfr_length ); /* rr[ k ] in Q( -rr_shifts ) */
+
/* Assure headroom */
LZs = SKP_Silk_CLZ32( rr[k] );
if( LZs < LTP_CORRS_HEAD_ROOM ) {
rr[ k ] = SKP_RSHIFT_ROUND( rr[ k ], LTP_CORRS_HEAD_ROOM - LZs );
- rr_shifts += (LTP_CORRS_HEAD_ROOM - LZs);
+ rr_shifts += ( LTP_CORRS_HEAD_ROOM - LZs );
}
corr_rshifts[ k ] = rr_shifts;
- SKP_Silk_corrMatrix_FIX( lag_ptr, subfr_length, LTP_ORDER, WLTP_ptr, &corr_rshifts[ k ] ); /* WLTP_fix_ptr in Q( -corr_rshifts[ k ] ) */
- /* The correlation vector always have lower max abs value than rr and/or RR so head room is assured */
- SKP_Silk_corrVector_FIX( lag_ptr, r_ptr, subfr_length, LTP_ORDER, Rr, corr_rshifts[ k ] ); /* Rr_fix_ptr in Q( -corr_rshifts[ k ] ) */
+ SKP_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 */
+ SKP_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 ] = SKP_RSHIFT( rr[ k ], corr_rshifts[ k ] - rr_shifts ); /* rr[ k ] in Q( -corr_rshifts[ k ] ) */
}
SKP_assert( rr[ k ] >= 0 );
- regu = SKP_SMULWB( rr[ k ] + 1, LTP_DAMPING_Q16 );
+ regu = SKP_SMULWB( rr[ k ] + 1, SKP_FIX_CONST( LTP_DAMPING, 16 ) );
SKP_Silk_regularize_correlations_FIX( WLTP_ptr, &rr[k], regu, LTP_ORDER );
SKP_Silk_solve_LDL_FIX( WLTP_ptr, LTP_ORDER, Rr, b_Q16 ); /* WLTP_fix_ptr and Rr_fix_ptr both in Q(-corr_rshifts[k]) */
@@ -96,12 +102,12 @@ void SKP_Silk_find_LTP_FIX( /* temp = Wght[ k ] / ( nrg[ k ] * Wght[ k ] + 0.01f * subfr_length ); */
extra_shifts = SKP_min_int( corr_rshifts[ k ], LTP_CORRS_HEAD_ROOM );
- denom32 = SKP_LSHIFT_SAT32( SKP_SMULWB( nrg[ k ], Wght_Q15[ k ] ), 1 + extra_shifts ) + /* Q( -corr_rshifts[ k ] + extra_shifts ) */
- SKP_RSHIFT( SKP_SMULWB( subfr_length, 655 ), corr_rshifts[ k ] - extra_shifts ); /* Q( -corr_rshifts[ k ] + extra_shifts ) */
+ denom32 = SKP_LSHIFT_SAT32( SKP_SMULWB( nrg[ k ], Wght_Q15[ k ] ), 1 + extra_shifts ) + /* Q( -corr_rshifts[ k ] + extra_shifts ) */
+ SKP_RSHIFT( SKP_SMULWB( subfr_length, 655 ), corr_rshifts[ k ] - extra_shifts ); /* Q( -corr_rshifts[ k ] + extra_shifts ) */
denom32 = SKP_max( denom32, 1 );
- SKP_assert( ((SKP_int64)Wght_Q15[ k ] << 16 ) < SKP_int32_MAX ); /* Wght always < 0.5 in Q0 */
- temp32 = SKP_DIV32( SKP_LSHIFT( ( SKP_int32 )Wght_Q15[ k ], 16 ), denom32 ); /* Q( 15 + 16 + corr_rshifts[k] - extra_shifts ) */
- temp32 = SKP_RSHIFT( temp32, 31 + corr_rshifts[ k ] - extra_shifts - 26 ); /* Q26 */
+ SKP_assert( ((SKP_int64)Wght_Q15[ k ] << 16 ) < SKP_int32_MAX ); /* Wght always < 0.5 in Q0 */
+ temp32 = SKP_DIV32( SKP_LSHIFT( ( SKP_int32 )Wght_Q15[ k ], 16 ), denom32 ); /* Q( 15 + 16 + corr_rshifts[k] - extra_shifts ) */
+ temp32 = SKP_RSHIFT( temp32, 31 + corr_rshifts[ k ] - extra_shifts - 26 ); /* Q26 */
/* Limit temp such that the below scaling never wraps around */
WLTP_max = 0;
@@ -129,7 +135,7 @@ void SKP_Silk_find_LTP_FIX( maxRshifts = SKP_max_int( corr_rshifts[ k ], maxRshifts );
}
- /* compute LTP coding gain */
+ /* Compute LTP coding gain */
if( LTPredCodGain_Q7 != NULL ) {
LPC_LTP_res_nrg = 0;
LPC_res_nrg = 0;
@@ -201,8 +207,8 @@ void SKP_Silk_find_LTP_FIX( g_Q26 = SKP_MUL(
SKP_DIV32(
- LTP_SMOOTHING_Q26,
- SKP_RSHIFT( LTP_SMOOTHING_Q26, 10 ) + temp32 ), /* Q10 */
+ SKP_FIX_CONST( LTP_SMOOTHING, 26 ),
+ SKP_RSHIFT( SKP_FIX_CONST( LTP_SMOOTHING, 26 ), 10 ) + temp32 ), /* Q10 */
SKP_LSHIFT_SAT32( SKP_SUB_SAT32( ( SKP_int32 )m_Q12, SKP_RSHIFT( d_Q14[ k ], 2 ) ), 4 ) ); /* Q16 */
temp32 = 0;
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