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add wide (64-bit) versions of the FIR filter and inverse filter, remove unused arg from quantizing routine

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Josh Coalson
2002-10-04 05:25:54 +00:00
parent b070fe6023
commit eac1024aea
2 changed files with 78 additions and 10 deletions
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83
src/libFLAC/lpc.c
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@@ -20,6 +20,7 @@
#include <math.h>
#include "FLAC/assert.h"
#include "FLAC/format.h"
#include "private/bitmath.h"
#include "private/lpc.h"
#if defined DEBUG || defined FLAC__OVERFLOW_DETECT || defined FLAC__OVERFLOW_DETECT_VERBOSE
#include <stdio.h>
@@ -109,7 +110,7 @@ void FLAC__lpc_compute_lp_coefficients(const FLAC__real autoc[], unsigned max_or
}
}
int FLAC__lpc_quantize_coefficients(const FLAC__real lp_coeff[], unsigned order, unsigned precision, unsigned bits_per_sample, FLAC__int32 qlp_coeff[], int *shift)
int FLAC__lpc_quantize_coefficients(const FLAC__real lp_coeff[], unsigned order, unsigned precision, FLAC__int32 qlp_coeff[], int *shift)
{
unsigned i;
double d, cmax = -1e32;
@@ -117,14 +118,8 @@ int FLAC__lpc_quantize_coefficients(const FLAC__real lp_coeff[], unsigned order,
const int max_shiftlimit = (1 << (FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN-1)) - 1;
const int min_shiftlimit = -max_shiftlimit - 1;
FLAC__ASSERT(bits_per_sample > 0);
FLAC__ASSERT(bits_per_sample <= sizeof(FLAC__int32)*8);
FLAC__ASSERT(precision > 0);
FLAC__ASSERT(precision >= FLAC__MIN_QLP_COEFF_PRECISION);
FLAC__ASSERT(precision + bits_per_sample < sizeof(FLAC__int32)*8);
#ifdef NDEBUG
(void)bits_per_sample; /* silence compiler warning about unused parameter */
#endif
/* drop one bit for the sign; from here on out we consider only |lp_coeff[i]| */
precision--;
@@ -152,7 +147,13 @@ redo_it:
*shift = (int)precision - log2cmax - 1;
if(*shift < min_shiftlimit || *shift > max_shiftlimit) {
return 1;
#if 0
/*@@@ this does not seem to help at all, but was not extensively tested either: */
if(*shift > max_shiftlimit)
*shift = max_shiftlimit;
else
#endif
return 1;
}
}
@@ -243,6 +244,39 @@ void FLAC__lpc_compute_residual_from_qlp_coefficients(const FLAC__int32 data[],
*/
}
void FLAC__lpc_compute_residual_from_qlp_coefficients_wide(const FLAC__int32 data[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 residual[])
{
unsigned i, j;
FLAC__int64 sum;
const FLAC__int32 *history;
#ifdef FLAC__OVERFLOW_DETECT_VERBOSE
fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients_wide: data_len=%d, order=%u, lpq=%d",data_len,order,lp_quantization);
for(i=0;i<order;i++)
fprintf(stderr,", q[%u]=%d",i,qlp_coeff[i]);
fprintf(stderr,"\n");
#endif
FLAC__ASSERT(order > 0);
for(i = 0; i < data_len; i++) {
sum = 0;
history = data;
for(j = 0; j < order; j++)
sum += (FLAC__int64)qlp_coeff[j] * (FLAC__int64)(*(--history));
#ifdef FLAC__OVERFLOW_DETECT
if(FLAC__bitmath_silog2_wide(sum >> lp_quantization) > 32) {
fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients_wide: OVERFLOW, i=%u, sum=%lld\n", i, sum >> lp_quantization);
break;
}
if(FLAC__bitmath_silog2_wide((FLAC__int64)(*data) - (sum >> lp_quantization)) > 32) {
fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients_wide: OVERFLOW, i=%u, data=%d, sum=%lld, residual=%lld\n", i, *data, sum >> lp_quantization, (FLAC__int64)(*data) - (sum >> lp_quantization));
break;
}
#endif
*(residual++) = *(data++) - (FLAC__int32)(sum >> lp_quantization);
}
}
void FLAC__lpc_restore_signal(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[])
{
#ifdef FLAC__OVERFLOW_DETECT
@@ -294,6 +328,39 @@ void FLAC__lpc_restore_signal(const FLAC__int32 residual[], unsigned data_len, c
*/
}
void FLAC__lpc_restore_signal_wide(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[])
{
unsigned i, j;
FLAC__int64 sum;
const FLAC__int32 *history;
#ifdef FLAC__OVERFLOW_DETECT_VERBOSE
fprintf(stderr,"FLAC__lpc_restore_signal_wide: data_len=%d, order=%u, lpq=%d",data_len,order,lp_quantization);
for(i=0;i<order;i++)
fprintf(stderr,", q[%u]=%d",i,qlp_coeff[i]);
fprintf(stderr,"\n");
#endif
FLAC__ASSERT(order > 0);
for(i = 0; i < data_len; i++) {
sum = 0;
history = data;
for(j = 0; j < order; j++)
sum += (FLAC__int64)qlp_coeff[j] * (FLAC__int64)(*(--history));
#ifdef FLAC__OVERFLOW_DETECT
if(FLAC__bitmath_silog2_wide(sum >> lp_quantization) > 32) {
fprintf(stderr,"FLAC__lpc_restore_signal_wide: OVERFLOW, i=%u, sum=%lld\n", i, sum >> lp_quantization);
break;
}
if(FLAC__bitmath_silog2_wide((FLAC__int64)(*residual) + (sum >> lp_quantization)) > 32) {
fprintf(stderr,"FLAC__lpc_restore_signal_wide: OVERFLOW, i=%u, residual=%d, sum=%lld, data=%lld\n", i, *residual, sum >> lp_quantization, (FLAC__int64)(*residual) + (sum >> lp_quantization));
break;
}
#endif
*(data++) = *(residual++) + (FLAC__int32)(sum >> lp_quantization);
}
}
FLAC__real FLAC__lpc_compute_expected_bits_per_residual_sample(FLAC__real lpc_error, unsigned total_samples)
{
double error_scale;