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broken attempt at removign STB_VORBIS_CODEBOOK_FLOAT option

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Sean Barrett 2015-11-08 19:13:32 -08:00
parent bc2219e1b3
commit fe74a8c223
1 changed files with 18 additions and 45 deletions
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63
stb_vorbis.c
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@ -493,14 +493,8 @@ enum STBVorbisError
// trade off storage for speed.
//#define STB_VORBIS_DIVIDES_IN_CODEBOOK
// STB_VORBIS_CODEBOOK_SHORTS
// The vorbis file format encodes VQ codebook floats as ax+b where a and
// b are floating point per-codebook constants, and x is a 16-bit int.
// Normally, stb_vorbis decodes them to floats rather than leaving them
// as 16-bit ints and computing ax+b while decoding. This is a speed/space
// tradeoff; you can save space by defining this flag.
#ifndef STB_VORBIS_CODEBOOK_SHORTS
#define STB_VORBIS_CODEBOOK_FLOATS
#ifdef STB_VORBIS_CODEBOOK_SHORTS
#error "STB_VORBIS_CODEBOOK_SHORTS is no longer supported as it produced incorrect results for some input formats"
#endif
// STB_VORBIS_DIVIDE_TABLE
@ -607,11 +601,7 @@ typedef signed int int32;
#define FALSE 0
#endif
#ifdef STB_VORBIS_CODEBOOK_FLOATS
typedef float codetype;
#else
typedef uint16 codetype;
#endif
// @NOTE
//
@ -1703,15 +1693,9 @@ static int codebook_decode_scalar(vorb *f, Codebook *c)
// CODEBOOK_ELEMENT_FAST is an optimization for the CODEBOOK_FLOATS case
// where we avoid one addition
#ifndef STB_VORBIS_CODEBOOK_FLOATS
#define CODEBOOK_ELEMENT(c,off) (c->multiplicands[off] * c->delta_value + c->minimum_value)
#define CODEBOOK_ELEMENT_FAST(c,off) (c->multiplicands[off] * c->delta_value)
#define CODEBOOK_ELEMENT_BASE(c) (c->minimum_value)
#else
#define CODEBOOK_ELEMENT(c,off) (c->multiplicands[off])
#define CODEBOOK_ELEMENT_FAST(c,off) (c->multiplicands[off])
#define CODEBOOK_ELEMENT_BASE(c) (0)
#endif
#define CODEBOOK_ELEMENT(c,off) (c->multiplicands[off] * c->delta_value + c->minimum_value)
#define CODEBOOK_ELEMENT_FAST(c,off) (c->multiplicands[off] * c->delta_value)
#define CODEBOOK_ELEMENT_BASE(c) (c->minimum_value)
static int codebook_decode_start(vorb *f, Codebook *c)
{
@ -3860,6 +3844,7 @@ static int start_decoder(vorb *f)
#ifndef STB_VORBIS_DIVIDES_IN_CODEBOOK
if (c->lookup_type == 1) {
int len, sparse = c->sparse;
float last=0;
// pre-expand the lookup1-style multiplicands, to avoid a divide in the inner loop
if (sparse) {
if (c->sorted_entries == 0) goto skip;
@ -3873,16 +3858,11 @@ static int start_decoder(vorb *f)
unsigned int div=1;
for (k=0; k < c->dimensions; ++k) {
int off = (z / div) % c->lookup_values;
#ifndef STB_VORBIS_CODEBOOK_FLOATS
c->multiplicands[j*c->dimensions + k] = mults[off];
#else
c->multiplicands[j*c->dimensions + k] = mults[off]*c->delta_value + c->minimum_value;
// in this case (and this case only) we could pre-expand c->sequence_p,
// and throw away the decode logic for it; have to ALSO do
// it in the case below, but it can only be done if
// STB_VORBIS_CODEBOOK_FLOATS
// !STB_VORBIS_DIVIDES_IN_CODEBOOK
#endif
float val = mults[off];
val = mults[off]*c->delta_value + c->minimum_value + last;
c->multiplicands[j*c->dimensions + k] = val;
if (c->sequence_p)
last = val;
if (k+1 < c->dimensions) {
if (div > UINT_MAX / (unsigned int) c->lookup_values) {
setup_temp_free(f, mults,sizeof(mults[0])*c->lookup_values);
@ -3898,15 +3878,16 @@ static int start_decoder(vorb *f)
else
#endif
{
float last=0;
CHECK(f);
c->multiplicands = (codetype *) setup_malloc(f, sizeof(c->multiplicands[0]) * c->lookup_values);
if (c->multiplicands == NULL) { setup_temp_free(f, mults,sizeof(mults[0])*c->lookup_values); return error(f, VORBIS_outofmem); }
#ifndef STB_VORBIS_CODEBOOK_FLOATS
memcpy(c->multiplicands, mults, sizeof(c->multiplicands[0]) * c->lookup_values);
#else
for (j=0; j < (int) c->lookup_values; ++j)
c->multiplicands[j] = mults[j] * c->delta_value + c->minimum_value;
#endif
for (j=0; j < (int) c->lookup_values; ++j) {
float val = mults[j] * c->delta_value + c->minimum_value + last;
c->multiplicands[j] = val;
if (c->sequence_p)
last = val;
}
setup_temp_free(f, mults,sizeof(mults[0])*c->lookup_values);
}
#ifndef STB_VORBIS_DIVIDES_IN_CODEBOOK
@ -3914,14 +3895,6 @@ static int start_decoder(vorb *f)
#endif
CHECK(f);
#ifdef STB_VORBIS_CODEBOOK_FLOATS
if (c->lookup_type == 2 && c->sequence_p) {
for (j=1; j < (int) (c->sparse ? c->sorted_entries : c->lookup_values); ++j)
c->multiplicands[j] += c->multiplicands[j-1];
CHECK(f);
c->sequence_p = 0;
}
#endif
}
CHECK(f);
}