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bink: get rid of double precision float use

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Add a small table of integers instead as this is simpler and
avoid rounding issues (though such rounding issues are unlikely in this case)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2012-02-06 19:28:22 +01:00
parent 062cd9acc1
commit 574e87943e
1 changed files with 16 additions and 22 deletions
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38
libavcodec/bink.c
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@ -1228,40 +1228,34 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac
static av_cold void binkb_calc_quant(void)
{
uint8_t inv_bink_scan[64];
double s[64];
static const int s[64]={
1073741824,1489322693,1402911301,1262586814,1073741824, 843633538, 581104888, 296244703,
1489322693,2065749918,1945893874,1751258219,1489322693,1170153332, 806015634, 410903207,
1402911301,1945893874,1832991949,1649649171,1402911301,1102260336, 759250125, 387062357,
1262586814,1751258219,1649649171,1484645031,1262586814, 992008094, 683307060, 348346918,
1073741824,1489322693,1402911301,1262586814,1073741824, 843633538, 581104888, 296244703,
843633538,1170153332,1102260336, 992008094, 843633538, 662838617, 456571181, 232757969,
581104888, 806015634, 759250125, 683307060, 581104888, 456571181, 314491699, 160326478,
296244703, 410903207, 387062357, 348346918, 296244703, 232757969, 160326478, 81733730,
};
int i, j;
for (j = 0; j < 8; j++) {
for (i = 0; i < 8; i++) {
if (j && j != 4)
if (i && i != 4)
s[j*8 + i] = cos(j * M_PI/16.0) * cos(i * M_PI/16.0) * 2.0;
else
s[j*8 + i] = cos(j * M_PI/16.0) * sqrt(2.0);
else
if (i && i != 4)
s[j*8 + i] = cos(i * M_PI/16.0) * sqrt(2.0);
else
s[j*8 + i] = 1.0;
}
}
#define C (1LL<<30)
for (i = 0; i < 64; i++)
inv_bink_scan[bink_scan[i]] = i;
for (j = 0; j < 16; j++) {
for (i = 0; i < 64; i++) {
int k = inv_bink_scan[i];
if (s[i] == 1.0) {
if (s[i] == C) {
binkb_intra_quant[j][k] = (1L << 12) * binkb_intra_seed[i] *
binkb_num[j]/binkb_den[j];
binkb_inter_quant[j][k] = (1L << 12) * binkb_inter_seed[i] *
binkb_num[j]/binkb_den[j];
} else {
binkb_intra_quant[j][k] = (1L << 12) * binkb_intra_seed[i] * s[i] *
binkb_num[j]/(double)binkb_den[j];
binkb_inter_quant[j][k] = (1L << 12) * binkb_inter_seed[i] * s[i] *
binkb_num[j]/(double)binkb_den[j];
binkb_intra_quant[j][k] = binkb_intra_seed[i] * (int64_t)s[i] *
binkb_num[j]/(binkb_den[j] * (C>>12));
binkb_inter_quant[j][k] = binkb_inter_seed[i] * (int64_t)s[i] *
binkb_num[j]/(binkb_den[j] * (C>>12));
}
}
}