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FFmpeg/libavcodec/i386/mpegvideo_mmx.c
Michael Niedermayer 28db7fce02 slow but accurate integer dct from IJG (should be ok with the LGPL as the old DCT is the fast integer DCT from IJG)
per context DCT selection

Originally committed as revision 878 to svn://svn.ffmpeg.org/ffmpeg/trunk
2002-08-29 23:55:32 +00:00

573 lines
17 KiB
C

/*
* The simplest mpeg encoder (well, it was the simplest!)
* Copyright (c) 2000,2001 Fabrice Bellard.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Optimized for ia32 cpus by Nick Kurshev <nickols_k@mail.ru>
* h263, mpeg1, mpeg2 dequantizer & draw_edges by Michael Niedermayer <michaelni@gmx.at>
*/
#include "../dsputil.h"
#include "../mpegvideo.h"
#include "../avcodec.h"
extern UINT8 zigzag_end[64];
extern UINT8 zigzag_direct_noperm[64];
extern UINT16 inv_zigzag_direct16[64];
extern UINT32 inverse[256];
#if 0
/* XXX: GL: I don't understand why this function needs optimization
(it is called only once per frame!), so I disabled it */
void MPV_frame_start(MpegEncContext *s)
{
if (s->pict_type == B_TYPE) {
__asm __volatile(
"movl (%1), %%eax\n\t"
"movl 4(%1), %%edx\n\t"
"movl 8(%1), %%ecx\n\t"
"movl %%eax, (%0)\n\t"
"movl %%edx, 4(%0)\n\t"
"movl %%ecx, 8(%0)\n\t"
:
:"r"(s->current_picture), "r"(s->aux_picture)
:"eax","edx","ecx","memory");
} else {
/* swap next and last */
__asm __volatile(
"movl (%1), %%eax\n\t"
"movl 4(%1), %%edx\n\t"
"movl 8(%1), %%ecx\n\t"
"xchgl (%0), %%eax\n\t"
"xchgl 4(%0), %%edx\n\t"
"xchgl 8(%0), %%ecx\n\t"
"movl %%eax, (%1)\n\t"
"movl %%edx, 4(%1)\n\t"
"movl %%ecx, 8(%1)\n\t"
"movl %%eax, (%2)\n\t"
"movl %%edx, 4(%2)\n\t"
"movl %%ecx, 8(%2)\n\t"
:
:"r"(s->last_picture), "r"(s->next_picture), "r"(s->current_picture)
:"eax","edx","ecx","memory");
}
}
#endif
static const unsigned long long int mm_wabs __attribute__ ((aligned(8))) = 0xffffffffffffffffULL;
static const unsigned long long int mm_wone __attribute__ ((aligned(8))) = 0x0001000100010001ULL;
static void dct_unquantize_h263_mmx(MpegEncContext *s,
DCTELEM *block, int n, int qscale)
{
int i, level, qmul, qadd, nCoeffs;
qmul = s->qscale << 1;
if (s->h263_aic && s->mb_intra)
qadd = 0;
else
qadd = (s->qscale - 1) | 1;
if (s->mb_intra) {
if (!s->h263_aic) {
if (n < 4)
block[0] = block[0] * s->y_dc_scale;
else
block[0] = block[0] * s->c_dc_scale;
}
for(i=1; i<8; i++) {
level = block[i];
if (level) {
if (level < 0) {
level = level * qmul - qadd;
} else {
level = level * qmul + qadd;
}
block[i] = level;
}
}
nCoeffs=64;
} else {
i = 0;
nCoeffs= zigzag_end[ s->block_last_index[n] ];
}
//printf("%d %d ", qmul, qadd);
asm volatile(
"movd %1, %%mm6 \n\t" //qmul
"packssdw %%mm6, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"movd %2, %%mm5 \n\t" //qadd
"pxor %%mm7, %%mm7 \n\t"
"packssdw %%mm5, %%mm5 \n\t"
"packssdw %%mm5, %%mm5 \n\t"
"psubw %%mm5, %%mm7 \n\t"
"pxor %%mm4, %%mm4 \n\t"
".balign 16\n\t"
"1: \n\t"
"movq (%0, %3), %%mm0 \n\t"
"movq 8(%0, %3), %%mm1 \n\t"
"pmullw %%mm6, %%mm0 \n\t"
"pmullw %%mm6, %%mm1 \n\t"
"movq (%0, %3), %%mm2 \n\t"
"movq 8(%0, %3), %%mm3 \n\t"
"pcmpgtw %%mm4, %%mm2 \n\t" // block[i] < 0 ? -1 : 0
"pcmpgtw %%mm4, %%mm3 \n\t" // block[i] < 0 ? -1 : 0
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"paddw %%mm7, %%mm0 \n\t"
"paddw %%mm7, %%mm1 \n\t"
"pxor %%mm0, %%mm2 \n\t"
"pxor %%mm1, %%mm3 \n\t"
"pcmpeqw %%mm7, %%mm0 \n\t" // block[i] == 0 ? -1 : 0
"pcmpeqw %%mm7, %%mm1 \n\t" // block[i] == 0 ? -1 : 0
"pandn %%mm2, %%mm0 \n\t"
"pandn %%mm3, %%mm1 \n\t"
"movq %%mm0, (%0, %3) \n\t"
"movq %%mm1, 8(%0, %3) \n\t"
"addl $16, %3 \n\t"
"js 1b \n\t"
::"r" (block+nCoeffs), "g"(qmul), "g" (qadd), "r" (2*(i-nCoeffs))
: "memory"
);
}
/*
NK:
Note: looking at PARANOID:
"enable all paranoid tests for rounding, overflows, etc..."
#ifdef PARANOID
if (level < -2048 || level > 2047)
fprintf(stderr, "unquant error %d %d\n", i, level);
#endif
We can suppose that result of two multiplications can't be greate of 0xFFFF
i.e. is 16-bit, so we use here only PMULLW instruction and can avoid
a complex multiplication.
=====================================================
Full formula for multiplication of 2 integer numbers
which are represent as high:low words:
input: value1 = high1:low1
value2 = high2:low2
output: value3 = value1*value2
value3=high3:low3 (on overflow: modulus 2^32 wrap-around)
this mean that for 0x123456 * 0x123456 correct result is 0x766cb0ce4
but this algorithm will compute only 0x66cb0ce4
this limited by 16-bit size of operands
---------------------------------
tlow1 = high1*low2
tlow2 = high2*low1
tlow1 = tlow1 + tlow2
high3:low3 = low1*low2
high3 += tlow1
*/
static void dct_unquantize_mpeg1_mmx(MpegEncContext *s,
DCTELEM *block, int n, int qscale)
{
int nCoeffs;
const UINT16 *quant_matrix;
if(s->alternate_scan) nCoeffs= 64;
else nCoeffs= zigzag_end[ s->block_last_index[n] ];
if (s->mb_intra) {
int block0;
if (n < 4)
block0 = block[0] * s->y_dc_scale;
else
block0 = block[0] * s->c_dc_scale;
/* XXX: only mpeg1 */
quant_matrix = s->intra_matrix;
asm volatile(
"pcmpeqw %%mm7, %%mm7 \n\t"
"psrlw $15, %%mm7 \n\t"
"movd %2, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"movl %3, %%eax \n\t"
".balign 16\n\t"
"1: \n\t"
"movq (%0, %%eax), %%mm0 \n\t"
"movq 8(%0, %%eax), %%mm1 \n\t"
"movq (%1, %%eax), %%mm4 \n\t"
"movq 8(%1, %%eax), %%mm5 \n\t"
"pmullw %%mm6, %%mm4 \n\t" // q=qscale*quant_matrix[i]
"pmullw %%mm6, %%mm5 \n\t" // q=qscale*quant_matrix[i]
"pxor %%mm2, %%mm2 \n\t"
"pxor %%mm3, %%mm3 \n\t"
"pcmpgtw %%mm0, %%mm2 \n\t" // block[i] < 0 ? -1 : 0
"pcmpgtw %%mm1, %%mm3 \n\t" // block[i] < 0 ? -1 : 0
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t" // abs(block[i])
"psubw %%mm3, %%mm1 \n\t" // abs(block[i])
"pmullw %%mm4, %%mm0 \n\t" // abs(block[i])*q
"pmullw %%mm5, %%mm1 \n\t" // abs(block[i])*q
"pxor %%mm4, %%mm4 \n\t"
"pxor %%mm5, %%mm5 \n\t" // FIXME slow
"pcmpeqw (%0, %%eax), %%mm4 \n\t" // block[i] == 0 ? -1 : 0
"pcmpeqw 8(%0, %%eax), %%mm5 \n\t" // block[i] == 0 ? -1 : 0
"psraw $3, %%mm0 \n\t"
"psraw $3, %%mm1 \n\t"
"psubw %%mm7, %%mm0 \n\t"
"psubw %%mm7, %%mm1 \n\t"
"por %%mm7, %%mm0 \n\t"
"por %%mm7, %%mm1 \n\t"
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t"
"psubw %%mm3, %%mm1 \n\t"
"pandn %%mm0, %%mm4 \n\t"
"pandn %%mm1, %%mm5 \n\t"
"movq %%mm4, (%0, %%eax) \n\t"
"movq %%mm5, 8(%0, %%eax) \n\t"
"addl $16, %%eax \n\t"
"js 1b \n\t"
::"r" (block+nCoeffs), "r"(quant_matrix+nCoeffs), "g" (qscale), "g" (-2*nCoeffs)
: "%eax", "memory"
);
block[0]= block0;
} else {
quant_matrix = s->inter_matrix;
asm volatile(
"pcmpeqw %%mm7, %%mm7 \n\t"
"psrlw $15, %%mm7 \n\t"
"movd %2, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"movl %3, %%eax \n\t"
".balign 16\n\t"
"1: \n\t"
"movq (%0, %%eax), %%mm0 \n\t"
"movq 8(%0, %%eax), %%mm1 \n\t"
"movq (%1, %%eax), %%mm4 \n\t"
"movq 8(%1, %%eax), %%mm5 \n\t"
"pmullw %%mm6, %%mm4 \n\t" // q=qscale*quant_matrix[i]
"pmullw %%mm6, %%mm5 \n\t" // q=qscale*quant_matrix[i]
"pxor %%mm2, %%mm2 \n\t"
"pxor %%mm3, %%mm3 \n\t"
"pcmpgtw %%mm0, %%mm2 \n\t" // block[i] < 0 ? -1 : 0
"pcmpgtw %%mm1, %%mm3 \n\t" // block[i] < 0 ? -1 : 0
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t" // abs(block[i])
"psubw %%mm3, %%mm1 \n\t" // abs(block[i])
"paddw %%mm0, %%mm0 \n\t" // abs(block[i])*2
"paddw %%mm1, %%mm1 \n\t" // abs(block[i])*2
"paddw %%mm7, %%mm0 \n\t" // abs(block[i])*2 + 1
"paddw %%mm7, %%mm1 \n\t" // abs(block[i])*2 + 1
"pmullw %%mm4, %%mm0 \n\t" // (abs(block[i])*2 + 1)*q
"pmullw %%mm5, %%mm1 \n\t" // (abs(block[i])*2 + 1)*q
"pxor %%mm4, %%mm4 \n\t"
"pxor %%mm5, %%mm5 \n\t" // FIXME slow
"pcmpeqw (%0, %%eax), %%mm4 \n\t" // block[i] == 0 ? -1 : 0
"pcmpeqw 8(%0, %%eax), %%mm5 \n\t" // block[i] == 0 ? -1 : 0
"psraw $4, %%mm0 \n\t"
"psraw $4, %%mm1 \n\t"
"psubw %%mm7, %%mm0 \n\t"
"psubw %%mm7, %%mm1 \n\t"
"por %%mm7, %%mm0 \n\t"
"por %%mm7, %%mm1 \n\t"
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t"
"psubw %%mm3, %%mm1 \n\t"
"pandn %%mm0, %%mm4 \n\t"
"pandn %%mm1, %%mm5 \n\t"
"movq %%mm4, (%0, %%eax) \n\t"
"movq %%mm5, 8(%0, %%eax) \n\t"
"addl $16, %%eax \n\t"
"js 1b \n\t"
::"r" (block+nCoeffs), "r"(quant_matrix+nCoeffs), "g" (qscale), "g" (-2*nCoeffs)
: "%eax", "memory"
);
}
}
static void dct_unquantize_mpeg2_mmx(MpegEncContext *s,
DCTELEM *block, int n, int qscale)
{
int nCoeffs;
const UINT16 *quant_matrix;
if(s->alternate_scan) nCoeffs= 64;
else nCoeffs= zigzag_end[ s->block_last_index[n] ];
if (s->mb_intra) {
int block0;
if (n < 4)
block0 = block[0] * s->y_dc_scale;
else
block0 = block[0] * s->c_dc_scale;
quant_matrix = s->intra_matrix;
asm volatile(
"pcmpeqw %%mm7, %%mm7 \n\t"
"psrlw $15, %%mm7 \n\t"
"movd %2, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"movl %3, %%eax \n\t"
".balign 16\n\t"
"1: \n\t"
"movq (%0, %%eax), %%mm0 \n\t"
"movq 8(%0, %%eax), %%mm1 \n\t"
"movq (%1, %%eax), %%mm4 \n\t"
"movq 8(%1, %%eax), %%mm5 \n\t"
"pmullw %%mm6, %%mm4 \n\t" // q=qscale*quant_matrix[i]
"pmullw %%mm6, %%mm5 \n\t" // q=qscale*quant_matrix[i]
"pxor %%mm2, %%mm2 \n\t"
"pxor %%mm3, %%mm3 \n\t"
"pcmpgtw %%mm0, %%mm2 \n\t" // block[i] < 0 ? -1 : 0
"pcmpgtw %%mm1, %%mm3 \n\t" // block[i] < 0 ? -1 : 0
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t" // abs(block[i])
"psubw %%mm3, %%mm1 \n\t" // abs(block[i])
"pmullw %%mm4, %%mm0 \n\t" // abs(block[i])*q
"pmullw %%mm5, %%mm1 \n\t" // abs(block[i])*q
"pxor %%mm4, %%mm4 \n\t"
"pxor %%mm5, %%mm5 \n\t" // FIXME slow
"pcmpeqw (%0, %%eax), %%mm4 \n\t" // block[i] == 0 ? -1 : 0
"pcmpeqw 8(%0, %%eax), %%mm5 \n\t" // block[i] == 0 ? -1 : 0
"psraw $3, %%mm0 \n\t"
"psraw $3, %%mm1 \n\t"
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t"
"psubw %%mm3, %%mm1 \n\t"
"pandn %%mm0, %%mm4 \n\t"
"pandn %%mm1, %%mm5 \n\t"
"movq %%mm4, (%0, %%eax) \n\t"
"movq %%mm5, 8(%0, %%eax) \n\t"
"addl $16, %%eax \n\t"
"js 1b \n\t"
::"r" (block+nCoeffs), "r"(quant_matrix+nCoeffs), "g" (qscale), "g" (-2*nCoeffs)
: "%eax", "memory"
);
block[0]= block0;
//Note, we dont do mismatch control for intra as errors cannot accumulate
} else {
quant_matrix = s->inter_matrix;
asm volatile(
"pcmpeqw %%mm7, %%mm7 \n\t"
"psrlq $48, %%mm7 \n\t"
"movd %2, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"packssdw %%mm6, %%mm6 \n\t"
"movl %3, %%eax \n\t"
".balign 16\n\t"
"1: \n\t"
"movq (%0, %%eax), %%mm0 \n\t"
"movq 8(%0, %%eax), %%mm1 \n\t"
"movq (%1, %%eax), %%mm4 \n\t"
"movq 8(%1, %%eax), %%mm5 \n\t"
"pmullw %%mm6, %%mm4 \n\t" // q=qscale*quant_matrix[i]
"pmullw %%mm6, %%mm5 \n\t" // q=qscale*quant_matrix[i]
"pxor %%mm2, %%mm2 \n\t"
"pxor %%mm3, %%mm3 \n\t"
"pcmpgtw %%mm0, %%mm2 \n\t" // block[i] < 0 ? -1 : 0
"pcmpgtw %%mm1, %%mm3 \n\t" // block[i] < 0 ? -1 : 0
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t" // abs(block[i])
"psubw %%mm3, %%mm1 \n\t" // abs(block[i])
"paddw %%mm0, %%mm0 \n\t" // abs(block[i])*2
"paddw %%mm1, %%mm1 \n\t" // abs(block[i])*2
"pmullw %%mm4, %%mm0 \n\t" // abs(block[i])*2*q
"pmullw %%mm5, %%mm1 \n\t" // abs(block[i])*2*q
"paddw %%mm4, %%mm0 \n\t" // (abs(block[i])*2 + 1)*q
"paddw %%mm5, %%mm1 \n\t" // (abs(block[i])*2 + 1)*q
"pxor %%mm4, %%mm4 \n\t"
"pxor %%mm5, %%mm5 \n\t" // FIXME slow
"pcmpeqw (%0, %%eax), %%mm4 \n\t" // block[i] == 0 ? -1 : 0
"pcmpeqw 8(%0, %%eax), %%mm5 \n\t" // block[i] == 0 ? -1 : 0
"psrlw $4, %%mm0 \n\t"
"psrlw $4, %%mm1 \n\t"
"pxor %%mm2, %%mm0 \n\t"
"pxor %%mm3, %%mm1 \n\t"
"psubw %%mm2, %%mm0 \n\t"
"psubw %%mm3, %%mm1 \n\t"
"pandn %%mm0, %%mm4 \n\t"
"pandn %%mm1, %%mm5 \n\t"
"pxor %%mm4, %%mm7 \n\t"
"pxor %%mm5, %%mm7 \n\t"
"movq %%mm4, (%0, %%eax) \n\t"
"movq %%mm5, 8(%0, %%eax) \n\t"
"addl $16, %%eax \n\t"
"js 1b \n\t"
"movd 124(%0, %3), %%mm0 \n\t"
"movq %%mm7, %%mm6 \n\t"
"psrlq $32, %%mm7 \n\t"
"pxor %%mm6, %%mm7 \n\t"
"movq %%mm7, %%mm6 \n\t"
"psrlq $16, %%mm7 \n\t"
"pxor %%mm6, %%mm7 \n\t"
"pslld $31, %%mm7 \n\t"
"psrlq $15, %%mm7 \n\t"
"pxor %%mm7, %%mm0 \n\t"
"movd %%mm0, 124(%0, %3) \n\t"
::"r" (block+nCoeffs), "r"(quant_matrix+nCoeffs), "g" (qscale), "r" (-2*nCoeffs)
: "%eax", "memory"
);
}
}
/* draw the edges of width 'w' of an image of size width, height
this mmx version can only handle w==8 || w==16 */
static void draw_edges_mmx(UINT8 *buf, int wrap, int width, int height, int w)
{
UINT8 *ptr, *last_line;
int i;
last_line = buf + (height - 1) * wrap;
/* left and right */
ptr = buf;
if(w==8)
{
asm volatile(
"1: \n\t"
"movd (%0), %%mm0 \n\t"
"punpcklbw %%mm0, %%mm0 \n\t"
"punpcklwd %%mm0, %%mm0 \n\t"
"punpckldq %%mm0, %%mm0 \n\t"
"movq %%mm0, -8(%0) \n\t"
"movq -8(%0, %2), %%mm1 \n\t"
"punpckhbw %%mm1, %%mm1 \n\t"
"punpckhwd %%mm1, %%mm1 \n\t"
"punpckhdq %%mm1, %%mm1 \n\t"
"movq %%mm1, (%0, %2) \n\t"
"addl %1, %0 \n\t"
"cmpl %3, %0 \n\t"
" jb 1b \n\t"
: "+r" (ptr)
: "r" (wrap), "r" (width), "r" (ptr + wrap*height)
);
}
else
{
asm volatile(
"1: \n\t"
"movd (%0), %%mm0 \n\t"
"punpcklbw %%mm0, %%mm0 \n\t"
"punpcklwd %%mm0, %%mm0 \n\t"
"punpckldq %%mm0, %%mm0 \n\t"
"movq %%mm0, -8(%0) \n\t"
"movq %%mm0, -16(%0) \n\t"
"movq -8(%0, %2), %%mm1 \n\t"
"punpckhbw %%mm1, %%mm1 \n\t"
"punpckhwd %%mm1, %%mm1 \n\t"
"punpckhdq %%mm1, %%mm1 \n\t"
"movq %%mm1, (%0, %2) \n\t"
"movq %%mm1, 8(%0, %2) \n\t"
"addl %1, %0 \n\t"
"cmpl %3, %0 \n\t"
" jb 1b \n\t"
: "+r" (ptr)
: "r" (wrap), "r" (width), "r" (ptr + wrap*height)
);
}
for(i=0;i<w;i+=4) {
/* top and bottom (and hopefully also the corners) */
ptr= buf - (i + 1) * wrap - w;
asm volatile(
"1: \n\t"
"movq (%1, %0), %%mm0 \n\t"
"movq %%mm0, (%0) \n\t"
"movq %%mm0, (%0, %2) \n\t"
"movq %%mm0, (%0, %2, 2) \n\t"
"movq %%mm0, (%0, %3) \n\t"
"addl $8, %0 \n\t"
"cmpl %4, %0 \n\t"
" jb 1b \n\t"
: "+r" (ptr)
: "r" ((int)buf - (int)ptr - w), "r" (-wrap), "r" (-wrap*3), "r" (ptr+width+2*w)
);
ptr= last_line + (i + 1) * wrap - w;
asm volatile(
"1: \n\t"
"movq (%1, %0), %%mm0 \n\t"
"movq %%mm0, (%0) \n\t"
"movq %%mm0, (%0, %2) \n\t"
"movq %%mm0, (%0, %2, 2) \n\t"
"movq %%mm0, (%0, %3) \n\t"
"addl $8, %0 \n\t"
"cmpl %4, %0 \n\t"
" jb 1b \n\t"
: "+r" (ptr)
: "r" ((int)last_line - (int)ptr - w), "r" (wrap), "r" (wrap*3), "r" (ptr+width+2*w)
);
}
}
static volatile int esp_temp;
void unused_var_warning_killer(){
esp_temp++;
}
#undef HAVE_MMX2
#define RENAME(a) a ## _MMX
#include "mpegvideo_mmx_template.c"
#define HAVE_MMX2
#undef RENAME
#define RENAME(a) a ## _MMX2
#include "mpegvideo_mmx_template.c"
void MPV_common_init_mmx(MpegEncContext *s)
{
if (mm_flags & MM_MMX) {
const int dct_algo= s->avctx->dct_algo;
s->dct_unquantize_h263 = dct_unquantize_h263_mmx;
s->dct_unquantize_mpeg1 = dct_unquantize_mpeg1_mmx;
s->dct_unquantize_mpeg2 = dct_unquantize_mpeg2_mmx;
draw_edges = draw_edges_mmx;
if(dct_algo==FF_DCT_AUTO || dct_algo==FF_DCT_MMX){
s->fdct = fdct_mmx;
if(mm_flags & MM_MMXEXT){
s->dct_quantize= dct_quantize_MMX2;
} else {
s->dct_quantize= dct_quantize_MMX;
}
}
}
}