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Sync opus codec to upstream git

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Change-Id: I0cfcc0005c4ad7bfbb1aaf454188ce70fb043dc1
This commit is contained in:
William Wilgus 2019-01-04 02:01:18 -06:00 • committed by Solomon Peachy
parent 75d9393796
commit 14c6bb798d
286 changed files with 48931 additions and 1278 deletions
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59
lib/rbcodec/codecs/libopus/silk/NLSF2A.c
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@ -66,7 +66,8 @@ static OPUS_INLINE void silk_NLSF2A_find_poly(
void silk_NLSF2A(
opus_int16 *a_Q12, /* O monic whitening filter coefficients in Q12, [ d ] */
const opus_int16 *NLSF, /* I normalized line spectral frequencies in Q15, [ d ] */
const opus_int d /* I filter order (should be even) */
const opus_int d, /* I filter order (should be even) */
int arch /* I Run-time architecture */
)
{
/* This ordering was found to maximize quality. It improves numerical accuracy of
@ -83,15 +84,14 @@ void silk_NLSF2A(
opus_int32 P[ SILK_MAX_ORDER_LPC / 2 + 1 ], Q[ SILK_MAX_ORDER_LPC / 2 + 1 ];
opus_int32 Ptmp, Qtmp, f_int, f_frac, cos_val, delta;
opus_int32 a32_QA1[ SILK_MAX_ORDER_LPC ];
opus_int32 maxabs, absval, idx=0, sc_Q16;
silk_assert( LSF_COS_TAB_SZ_FIX == 128 );
silk_assert( d==10||d==16 );
celt_assert( d==10 || d==16 );
/* convert LSFs to 2*cos(LSF), using piecewise linear curve from table */
ordering = d == 16 ? ordering16 : ordering10;
for( k = 0; k < d; k++ ) {
silk_assert(NLSF[k] >= 0 );
silk_assert( NLSF[k] >= 0 );
/* f_int on a scale 0-127 (rounded down) */
f_int = silk_RSHIFT( NLSF[k], 15 - 7 );
@ -126,52 +126,15 @@ void silk_NLSF2A(
a32_QA1[ d-k-1 ] = Qtmp - Ptmp; /* QA+1 */
}
/* Limit the maximum absolute value of the prediction coefficients, so that they'll fit in int16 */
for( i = 0; i < 10; i++ ) {
/* Find maximum absolute value and its index */
maxabs = 0;
for( k = 0; k < d; k++ ) {
absval = silk_abs( a32_QA1[k] );
if( absval > maxabs ) {
maxabs = absval;
idx = k;
}
}
maxabs = silk_RSHIFT_ROUND( maxabs, QA + 1 - 12 ); /* QA+1 -> Q12 */
/* Convert int32 coefficients to Q12 int16 coefs */
silk_LPC_fit( a_Q12, a32_QA1, 12, QA + 1, d );
if( maxabs > silk_int16_MAX ) {
/* Reduce magnitude of prediction coefficients */
maxabs = silk_min( maxabs, 163838 ); /* ( silk_int32_MAX >> 14 ) + silk_int16_MAX = 163838 */
sc_Q16 = SILK_FIX_CONST( 0.999, 16 ) - silk_DIV32( silk_LSHIFT( maxabs - silk_int16_MAX, 14 ),
silk_RSHIFT32( silk_MUL( maxabs, idx + 1), 2 ) );
silk_bwexpander_32( a32_QA1, d, sc_Q16 );
} else {
break;
}
}
if( i == 10 ) {
/* Reached the last iteration, clip the coefficients */
for( i = 0; silk_LPC_inverse_pred_gain( a_Q12, d, arch ) == 0 && i < MAX_LPC_STABILIZE_ITERATIONS; i++ ) {
/* Prediction coefficients are (too close to) unstable; apply bandwidth expansion */
/* on the unscaled coefficients, convert to Q12 and measure again */
silk_bwexpander_32( a32_QA1, d, 65536 - silk_LSHIFT( 2, i ) );
for( k = 0; k < d; k++ ) {
a_Q12[ k ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ) ); /* QA+1 -> Q12 */
a32_QA1[ k ] = silk_LSHIFT( (opus_int32)a_Q12[ k ], QA + 1 - 12 );
}
} else {
for( k = 0; k < d; k++ ) {
a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ); /* QA+1 -> Q12 */
}
}
for( i = 0; i < MAX_LPC_STABILIZE_ITERATIONS; i++ ) {
if( silk_LPC_inverse_pred_gain( a_Q12, d ) < SILK_FIX_CONST( 1.0 / MAX_PREDICTION_POWER_GAIN, 30 ) ) {
/* Prediction coefficients are (too close to) unstable; apply bandwidth expansion */
/* on the unscaled coefficients, convert to Q12 and measure again */
silk_bwexpander_32( a32_QA1, d, 65536 - silk_LSHIFT( 2, i ) );
for( k = 0; k < d; k++ ) {
a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ); /* QA+1 -> Q12 */
}
} else {
break;
a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ); /* QA+1 -> Q12 */
}
}
}