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remove old version of the lpcoeff quantizer, other debug detritus

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This commit is contained in:
Josh Coalson
2001-02-28 23:57:09 +00:00
parent c625f9033c
commit f40667b224
1 changed files with 1 additions and 51 deletions
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52
src/libFLAC/lpc.c
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@@ -84,50 +84,7 @@ void FLAC__lpc_compute_lp_coefficients(const real autoc[], unsigned max_order, r
int FLAC__lpc_quantize_coefficients(const real lp_coeff[], unsigned order, unsigned precision, unsigned bits_per_sample, int32 qlp_coeff[], int *shift) int FLAC__lpc_quantize_coefficients(const real lp_coeff[], unsigned order, unsigned precision, unsigned bits_per_sample, int32 qlp_coeff[], int *shift)
{ {
unsigned i; unsigned i;
real d, rprecision = (real)precision, maxlog = -1e99, minlog = 1e99; real d, cmax = -1e99;
assert(bits_per_sample > 0);
assert(bits_per_sample <= sizeof(int32)*8);
assert(precision >= FLAC__MIN_QLP_COEFF_PRECISION);
assert(precision + bits_per_sample < sizeof(int32)*8);
#ifdef NDEBUG
(void)bits_per_sample; /* silence compiler warning about unused parameter */
#endif
for(i = 0; i < order; i++) {
if(lp_coeff[i] == 0.0)
continue;
d = log(fabs(lp_coeff[i])) / M_LN2;
if(d > maxlog)
maxlog = d;
if(d < minlog)
minlog = d;
}
if(maxlog < minlog)
return 2;
else if(maxlog - minlog >= (real)(precision+1))
return 1;
else if((rprecision-1.0) - maxlog >= (real)(precision+1))
rprecision = (real)precision + maxlog + 1.0;
*shift = (int)floor((rprecision-1.0) - maxlog); /* '-1' because *shift can be negative and the sign bit costs 1 bit */
if(*shift > (int)precision || *shift <= -(int)precision) {
fprintf(stderr, "@@@ FLAC__lpc_quantize_coefficients(): ERROR: *shift=%d, maxlog=%f, minlog=%f, precision=%u, rprecision=%f\n", *shift, maxlog, minlog, precision, rprecision);
return 1;
}
if(*shift != 0) { /* just to avoid wasting time... */
for(i = 0; i < order; i++)
qlp_coeff[i] = (int32)floor(lp_coeff[i] * (real)(1 << *shift));
}
return 0;
}
#endif
int FLAC__lpc_quantize_coefficients(const real lp_coeff[], unsigned order, unsigned precision, unsigned bits_per_sample, int32 qlp_coeff[], int *shift)
{
unsigned i;
real d, cmax = -1e99;//@@@, cmin = 1e99;
assert(bits_per_sample > 0); assert(bits_per_sample > 0);
assert(bits_per_sample <= sizeof(int32)*8); assert(bits_per_sample <= sizeof(int32)*8);
@@ -147,26 +104,19 @@ int FLAC__lpc_quantize_coefficients(const real lp_coeff[], unsigned order, unsig
d = fabs(lp_coeff[i]); d = fabs(lp_coeff[i]);
if(d > cmax) if(d > cmax)
cmax = d; cmax = d;
//@@@ if(d < cmin)
//@@@ cmin = d;
} }
//@@@ if(cmax < cmin)
if(cmax < 0) { if(cmax < 0) {
/* => coeffients are all 0, which means our constant-detect didn't work */ /* => coeffients are all 0, which means our constant-detect didn't work */
fprintf(stderr,"@@@ LPCQ ERROR, all lpc_coeffs are 0\n");
return 2; return 2;
} }
else { else {
//@@@ const int minshift = (int)precision - floor(log(cmin) / M_LN2) - 1;
const int maxshift = (int)precision - floor(log(cmax) / M_LN2) - 1; const int maxshift = (int)precision - floor(log(cmax) / M_LN2) - 1;
//@@@ assert(maxshift >= minshift);
const int max_shiftlimit = (1 << (FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN-1)) - 1; const int max_shiftlimit = (1 << (FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN-1)) - 1;
const int min_shiftlimit = -max_shiftlimit - 1; const int min_shiftlimit = -max_shiftlimit - 1;
*shift = maxshift; *shift = maxshift;
if(*shift < min_shiftlimit || *shift > max_shiftlimit) { if(*shift < min_shiftlimit || *shift > max_shiftlimit) {
fprintf(stderr,"@@@ LPCQ ERROR, shift is outside shiftlimit\n");
return 1; return 1;
} }
} }