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Update and activate dct_unquantize_h263_mvi. Thanks to Måns Rullgård

Browse Source 
for some improvements.

Originally committed as revision 714 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Falk Hüffner 2002-07-03 03:01:06 +00:00
parent dde3f77dbc
commit e0580f8c68
3 changed files with 56 additions and 49 deletions
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99
libavcodec/alpha/mpegvideo_alpha.c
View File

@ -23,69 +23,70 @@
extern UINT8 zigzag_end[64];
static void dct_unquantize_h263_axp(MpegEncContext *s,
DCTELEM *block, int n, int qscale)
static void dct_unquantize_h263_mvi(MpegEncContext *s, DCTELEM *block,
int n, int qscale)
{
int i, level;
UINT64 qmul, qadd;
int i, n_coeffs;
uint64_t qmul, qadd;
uint64_t correction;
DCTELEM *orig_block = block;
DCTELEM block0;
ASM_ACCEPT_MVI;
if (s->mb_intra) {
if (n < 4)
block[0] = block[0] * s->y_dc_scale;
else
block[0] = block[0] * s->c_dc_scale;
/* Catch up to aligned point. */
qmul = s->qscale << 1;
qadd = (s->qscale - 1) | 1;
for (i = 1; i < 4; ++i) {
level = block[i];
if (level) {
if (level < 0) {
level = level * qmul - qadd;
} else {
level = level * qmul + qadd;
}
block[i] = level;
}
}
block += 4;
i = 60 / 4;
if (!s->h263_aic) {
if (n < 4)
block0 = block[0] * s->y_dc_scale;
else
block0 = block[0] * s->c_dc_scale;
}
n_coeffs = 64; // does not always use zigzag table
} else {
i = zigzag_end[s->block_last_index[n]] / 4;
n_coeffs = zigzag_end[s->block_last_index[n]];
}
qmul = s->qscale << 1;
qmul = qscale << 1;
qadd = WORD_VEC((qscale - 1) | 1);
do {
UINT64 levels, negmask, zeromask, corr;
levels = ldq(block);
if (levels == 0)
continue;
zeromask = cmpbge(0, levels);
zeromask &= zeromask >> 1;
/* Negate all negative words. */
negmask = maxsw4(levels, WORD_VEC(0xffff)); /* negative -> ffff (-1) */
negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */
corr = negmask & WORD_VEC(0x0001); /* twos-complement correction */
levels ^= negmask;
levels += corr;
/* This mask kills spill from negative subwords to the next subword. */
correction = WORD_VEC((qmul - 1) + 1); /* multiplication / addition */
levels = levels * qmul;
levels += zap(qadd, zeromask);
for(i = 0; i < n_coeffs; block += 4, i += 4) {
uint64_t levels, negmask, zeros, add;
/* Re-negate negative words. */
levels -= corr;
levels ^= negmask;
levels = ldq(block);
if (levels == 0)
continue;
stq(levels, block);
} while (block += 4, --i);
negmask = maxsw4(levels, -1); /* negative -> ffff (-1) */
negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */
zeros = cmpbge(0, levels);
zeros &= zeros >> 1;
/* zeros |= zeros << 1 is not needed since qadd <= 255, so
zapping the lower byte suffices. */
levels *= qmul;
levels -= correction & (negmask << 16);
/* Negate qadd for negative levels. */
add = qadd ^ negmask;
add += WORD_VEC(0x0001) & negmask;
/* Set qadd to 0 for levels == 0. */
add = zap(add, zeros);
levels += add;
stq(levels, block);
}
if (s->mb_intra && !s->h263_aic)
orig_block[0] = block0;
}
void MPV_common_init_axp(MpegEncContext *s)
{
if (amask(AMASK_MVI) == 0) {
if (s->out_format == FMT_H263)
s->dct_unquantize = dct_unquantize_h263_axp;
s->dct_unquantize_h263 = dct_unquantize_h263_mvi;
}
}

3
libavcodec/mpegvideo.c
View File

@ -131,6 +131,9 @@ int MPV_common_init(MpegEncContext *s)
#ifdef HAVE_MMX
MPV_common_init_mmx(s);
#endif
#ifdef ARCH_ALPHA
MPV_common_init_axp(s);
#endif
//setup default unquantizers (mpeg4 might change it later)
if(s->out_format == FMT_H263)

3
libavcodec/mpegvideo.h
View File

@ -451,6 +451,9 @@ void MPV_frame_end(MpegEncContext *s);
#ifdef HAVE_MMX
void MPV_common_init_mmx(MpegEncContext *s);
#endif
#ifdef ARCH_ALPHA
void MPV_common_init_axp(MpegEncContext *s);
#endif
extern int (*dct_quantize)(MpegEncContext *s, DCTELEM *block, int n, int qscale, int *overflow);
extern void (*draw_edges)(UINT8 *buf, int wrap, int width, int height, int w);
void ff_conceal_past_errors(MpegEncContext *s, int conceal_all);