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Merge commit '0a6664706168dc1049967bec311970d720581625'

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* commit '0a6664706168dc1049967bec311970d720581625':
  mpegvideo_enc: factor out denominator and explicitly cast operands

Conflicts:
	libavcodec/mpegvideo_enc.c

See: c753b56b4d
Merged-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2014-11-06 17:21:11 +01:00
commit c96a44d0dd
1 changed files with 7 additions and 8 deletions
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15
libavcodec/mpegvideo_enc.c
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@ -96,41 +96,40 @@ void ff_convert_matrix(MpegEncContext *s, int (*qmat)[64],
fdsp->fdct == ff_jpeg_fdct_islow_10) {
for (i = 0; i < 64; i++) {
const int j = s->idsp.idct_permutation[i];
int64_t den = (int64_t) qscale * quant_matrix[j];
/* 16 <= qscale * quant_matrix[i] <= 7905
* Assume x = ff_aanscales[i] * qscale * quant_matrix[i]
* 19952 <= x <= 249205026
* (1 << 36) / 19952 >= (1 << 36) / (x) >= (1 << 36) / 249205026
* 3444240 >= (1 << 36) / (x) >= 275 */
qmat[qscale][i] = (int)((UINT64_C(1) << QMAT_SHIFT) /
(qscale * quant_matrix[j]));
qmat[qscale][i] = (int)((UINT64_C(1) << QMAT_SHIFT) / den);
}
} else if (fdsp->fdct == ff_fdct_ifast) {
for (i = 0; i < 64; i++) {
const int j = s->idsp.idct_permutation[i];
int64_t den = ff_aanscales[i] * (int64_t) qscale * quant_matrix[j];
/* 16 <= qscale * quant_matrix[i] <= 7905
* Assume x = ff_aanscales[i] * qscale * quant_matrix[i]
* 19952 <= x <= 249205026
* (1 << 36) / 19952 >= (1 << 36) / (x) >= (1 << 36) / 249205026
* 3444240 >= (1 << 36) / (x) >= 275 */
qmat[qscale][i] = (int)((UINT64_C(1) << (QMAT_SHIFT + 14)) /
(ff_aanscales[i] * (int64_t)qscale * quant_matrix[j]));
qmat[qscale][i] = (int)((UINT64_C(1) << (QMAT_SHIFT + 14)) / den);
}
} else {
for (i = 0; i < 64; i++) {
const int j = s->idsp.idct_permutation[i];
int64_t den = (int64_t) qscale * quant_matrix[j];
/* We can safely suppose that 16 <= quant_matrix[i] <= 255
* Assume x = qscale * quant_matrix[i]
* So 16 <= x <= 7905
* so (1 << 19) / 16 >= (1 << 19) / (x) >= (1 << 19) / 7905
* so 32768 >= (1 << 19) / (x) >= 67 */
qmat[qscale][i] = (int)((UINT64_C(1) << QMAT_SHIFT) /
(qscale * quant_matrix[j]));
qmat[qscale][i] = (int)((UINT64_C(1) << QMAT_SHIFT) / den);
//qmat [qscale][i] = (1 << QMAT_SHIFT_MMX) /
// (qscale * quant_matrix[i]);
qmat16[qscale][0][i] = (1 << QMAT_SHIFT_MMX) /
(qscale * quant_matrix[j]);
qmat16[qscale][0][i] = (1 << QMAT_SHIFT_MMX) / den;
if (qmat16[qscale][0][i] == 0 ||
qmat16[qscale][0][i] == 128 * 256)