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fix the case in the coeff quantizer where the coeffs were not quantized when the shift is zero

This commit is contained in:
Josh Coalson 2001-07-06 00:37:57 +00:00
parent 6d5be83970
commit 4e6b3ac2ac
1 changed files with 25 additions and 26 deletions
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51
src/libFLAC/lpc.c
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@ -155,38 +155,37 @@ redo_it:
}
}
if(*shift != 0) { /* just to avoid wasting time... */
if(*shift > 0) {
for(i = 0; i < order; i++) {
qlp_coeff[i] = (FLAC__int32)floor((double)lp_coeff[i] * (double)(1 << *shift));
if(*shift >= 0) {
for(i = 0; i < order; i++) {
qlp_coeff[i] = (FLAC__int32)floor((double)lp_coeff[i] * (double)(1 << *shift));
/* check for corner cases mentioned in the comment for log2cmax above */
if(qlp_coeff[i] > qmax || qlp_coeff[i] < qmin) {
/* check for corner cases mentioned in the comment for log2cmax above */
if(qlp_coeff[i] > qmax || qlp_coeff[i] < qmin) {
#ifdef FLAC__OVERFLOW_DETECT
fprintf(stderr,"FLAC__lpc_quantize_coefficients: compensating for overflow, qlp_coeff[%u]=%d, lp_coeff[%u]=%f, cmax=%f, precision=%u, shift=%d, q=%f, f(q)=%f\n", i, qlp_coeff[i], i, lp_coeff[i], cmax, precision, *shift, (double)lp_coeff[i] * (double)(1 << *shift), floor((double)lp_coeff[i] * (double)(1 << *shift)));
fprintf(stderr,"FLAC__lpc_quantize_coefficients: compensating for overflow, qlp_coeff[%u]=%d, lp_coeff[%u]=%f, cmax=%f, precision=%u, shift=%d, q=%f, f(q)=%f\n", i, qlp_coeff[i], i, lp_coeff[i], cmax, precision, *shift, (double)lp_coeff[i] * (double)(1 << *shift), floor((double)lp_coeff[i] * (double)(1 << *shift)));
#endif
cmax *= 2.0;
goto redo_it;
}
}
}
else { /* (*shift < 0) */
const int nshift = -(*shift);
fprintf(stderr,"FLAC__lpc_quantize_coefficients: negative shift = %d\n", *shift);
for(i = 0; i < order; i++) {
qlp_coeff[i] = (FLAC__int32)floor((double)lp_coeff[i] / (double)(1 << nshift));
/* check for corner cases mentioned in the comment for log2cmax above */
if(qlp_coeff[i] > qmax || qlp_coeff[i] < qmin) {
#ifdef FLAC__OVERFLOW_DETECT
fprintf(stderr,"FLAC__lpc_quantize_coefficients: compensating for overflow, qlp_coeff[%u]=%d, lp_coeff[%u]=%f, cmax=%f, precision=%u, shift=%d, q=%f, f(q)=%f\n", i, qlp_coeff[i], i, lp_coeff[i], cmax, precision, *shift, (double)lp_coeff[i] / (double)(1 << nshift), floor((double)lp_coeff[i] / (double)(1 << nshift)));
#endif
cmax *= 2.0;
goto redo_it;
}
cmax *= 2.0;
goto redo_it;
}
}
}
else { /* (*shift < 0) */
const int nshift = -(*shift);
fprintf(stderr,"FLAC__lpc_quantize_coefficients: negative shift = %d\n", *shift);
for(i = 0; i < order; i++) {
qlp_coeff[i] = (FLAC__int32)floor((double)lp_coeff[i] / (double)(1 << nshift));
/* check for corner cases mentioned in the comment for log2cmax above */
if(qlp_coeff[i] > qmax || qlp_coeff[i] < qmin) {
#ifdef FLAC__OVERFLOW_DETECT
fprintf(stderr,"FLAC__lpc_quantize_coefficients: compensating for overflow, qlp_coeff[%u]=%d, lp_coeff[%u]=%f, cmax=%f, precision=%u, shift=%d, q=%f, f(q)=%f\n", i, qlp_coeff[i], i, lp_coeff[i], cmax, precision, *shift, (double)lp_coeff[i] / (double)(1 << nshift), floor((double)lp_coeff[i] / (double)(1 << nshift)));
#endif
cmax *= 2.0;
goto redo_it;
}
}
}
return 0;
}