2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 * @brief IntraX8 (J-Frame) subdecoder, used by WMV2 and VC-1
25 #include "bitstream.h"
26 #include "mpegvideo.h"
27 #include "msmpeg4data.h"
28 #include "intrax8huf.h"
31 #define MAX_TABLE_DEPTH(table_bits, max_bits) ((max_bits+table_bits-1)/table_bits)
37 #define DC_VLC_MTD MAX_TABLE_DEPTH(DC_VLC_BITS, MAX_DC_VLC_BITS)
38 #define AC_VLC_MTD MAX_TABLE_DEPTH(AC_VLC_BITS, MAX_AC_VLC_BITS)
39 #define OR_VLC_MTD MAX_TABLE_DEPTH(OR_VLC_BITS, MAX_OR_VLC_BITS)
41 static VLC j_ac_vlc
[2][2][8]; //[quant<13],[intra/inter],[select]
42 static VLC j_dc_vlc
[2][8]; //[quant], [select]
43 static VLC j_orient_vlc
[2][4]; //[quant], [select]
45 static void x8_vlc_init(){
48 #define init_ac_vlc(dst,src) \
56 init_ac_vlc( j_ac_vlc
[0][0][i
], x8_ac0_highquant_table
[i
][0] );
57 init_ac_vlc( j_ac_vlc
[0][1][i
], x8_ac1_highquant_table
[i
][0] );
58 init_ac_vlc( j_ac_vlc
[1][0][i
], x8_ac0_lowquant_table
[i
][0] );
59 init_ac_vlc( j_ac_vlc
[1][1][i
], x8_ac1_lowquant_table
[i
][0] );
64 #define init_dc_vlc(dst,src) \
71 init_dc_vlc( j_dc_vlc
[0][i
], x8_dc_highquant_table
[i
][0]);
72 init_dc_vlc( j_dc_vlc
[1][i
], x8_dc_lowquant_table
[i
][0]);
77 #define init_or_vlc(dst,src) \
84 init_or_vlc( j_orient_vlc
[0][i
], x8_orient_highquant_table
[i
][0]);
87 init_or_vlc( j_orient_vlc
[1][i
], x8_orient_lowquant_table
[i
][0])
92 static void x8_reset_vlc_tables(IntraX8Context
* w
){
93 memset(w
->j_dc_vlc
,0,sizeof(w
->j_dc_vlc
));
94 memset(w
->j_ac_vlc
,0,sizeof(w
->j_ac_vlc
));
98 static inline void x8_select_ac_table(IntraX8Context
* const w
, int mode
){
99 MpegEncContext
* const s
= w
->s
;
104 if( w
->j_ac_vlc
[mode
] ) return;
106 table_index
= get_bits(&s
->gb
, 3);
107 w
->j_ac_vlc
[mode
] = &j_ac_vlc
[w
->quant
<13][mode
>>1][table_index
];//2 modes use same tables
108 assert(w
->j_ac_vlc
[mode
]);
111 static inline int x8_get_orient_vlc(IntraX8Context
* w
){
112 MpegEncContext
* const s
= w
->s
;
115 if(!w
->j_orient_vlc
){
116 table_index
= get_bits(&s
->gb
, 1+(w
->quant
<13) );
117 w
->j_orient_vlc
= &j_orient_vlc
[w
->quant
<13][table_index
];
119 assert(w
->j_orient_vlc
);
120 assert(w
->j_orient_vlc
->table
);
122 return get_vlc2(&s
->gb
, w
->j_orient_vlc
->table
, OR_VLC_BITS
, OR_VLC_MTD
);
125 #define extra_bits(eb) (eb)
126 #define extra_run (0xFF<<8)
127 #define extra_level (0x00<<8)
128 #define run_offset(r) ((r)<<16)
129 #define level_offset(l) ((l)<<24)
130 static const uint32_t ac_decode_table
[]={
131 /*46*/ extra_bits(3) | extra_run
| run_offset(16) | level_offset( 0),
132 /*47*/ extra_bits(3) | extra_run
| run_offset(24) | level_offset( 0),
133 /*48*/ extra_bits(2) | extra_run
| run_offset( 4) | level_offset( 1),
134 /*49*/ extra_bits(3) | extra_run
| run_offset( 8) | level_offset( 1),
136 /*50*/ extra_bits(5) | extra_run
| run_offset(32) | level_offset( 0),
137 /*51*/ extra_bits(4) | extra_run
| run_offset(16) | level_offset( 1),
139 /*52*/ extra_bits(2) | extra_level
| run_offset( 0) | level_offset( 4),
140 /*53*/ extra_bits(2) | extra_level
| run_offset( 0) | level_offset( 8),
141 /*54*/ extra_bits(2) | extra_level
| run_offset( 0) | level_offset(12),
142 /*55*/ extra_bits(3) | extra_level
| run_offset( 0) | level_offset(16),
143 /*56*/ extra_bits(3) | extra_level
| run_offset( 0) | level_offset(24),
145 /*57*/ extra_bits(2) | extra_level
| run_offset( 1) | level_offset( 3),
146 /*58*/ extra_bits(3) | extra_level
| run_offset( 1) | level_offset( 7),
148 /*59*/ extra_bits(2) | extra_run
| run_offset(16) | level_offset( 0),
149 /*60*/ extra_bits(2) | extra_run
| run_offset(20) | level_offset( 0),
150 /*61*/ extra_bits(2) | extra_run
| run_offset(24) | level_offset( 0),
151 /*62*/ extra_bits(2) | extra_run
| run_offset(28) | level_offset( 0),
152 /*63*/ extra_bits(4) | extra_run
| run_offset(32) | level_offset( 0),
153 /*64*/ extra_bits(4) | extra_run
| run_offset(48) | level_offset( 0),
155 /*65*/ extra_bits(2) | extra_run
| run_offset( 4) | level_offset( 1),
156 /*66*/ extra_bits(3) | extra_run
| run_offset( 8) | level_offset( 1),
157 /*67*/ extra_bits(4) | extra_run
| run_offset(16) | level_offset( 1),
159 /*68*/ extra_bits(2) | extra_level
| run_offset( 0) | level_offset( 4),
160 /*69*/ extra_bits(3) | extra_level
| run_offset( 0) | level_offset( 8),
161 /*70*/ extra_bits(4) | extra_level
| run_offset( 0) | level_offset(16),
163 /*71*/ extra_bits(2) | extra_level
| run_offset( 1) | level_offset( 3),
164 /*72*/ extra_bits(3) | extra_level
| run_offset( 1) | level_offset( 7),
166 //extra_bits = 3bits; extra_run/level = 1 bit; run_offset = 6bits; level_offset = 5 bits;
173 static void x8_get_ac_rlf(IntraX8Context
* const w
, const int mode
,
174 int * const run
, int * const level
, int * const final
){
175 MpegEncContext
* const s
= w
->s
;
178 // x8_select_ac_table(w,mode);
179 i
= get_vlc2(&s
->gb
, w
->j_ac_vlc
[mode
]->table
, AC_VLC_BITS
, AC_VLC_MTD
);
184 (*level
)=(*final
)=//prevent 'may be used unilitialized'
185 (*run
)=64;//this would cause error exit in the ac loop
189 (*final
) = t
= (i
>22);
192 i== 0-15 r=0-15 l=0 ;r=i& %01111
193 i==16-19 r=0-3 l=1 ;r=i& %00011
194 i==20-21 r=0-1 l=2 ;r=i& %00001
195 i==22 r=0 l=3 ;r=i& %00000
196 l=lut_l[i/2]={0,0,0,0,0,0,0,0,1,1,2,3}[i>>1];// 11 10'01 01'00 00'00 00'00 00'00 00 => 0xE50000
197 t=lut_mask[l]={0x0f,0x03,0x01,0x00}[l]; as i<256 the higher bits do not matter */
198 l
=(0xE50000>>(i
&(0x1E)))&3;/*0x1E or (~1) or ((i>>1)<<1)*/
199 t
=(0x01030F>>(l
<<3));
203 }else if(i
<73){//[46-72]
208 sm
=ac_decode_table
[i
];
210 e
=get_bits(&s
->gb
,sm
&0xF);sm
>>=8;//3bits
211 mask
=sm
&0xff;sm
>>=8; //1bit
213 (*run
) =(sm
&0xff) + (e
&( mask
));//6bits
214 (*level
)=(sm
>>8) + (e
&(~mask
));//5bits
216 }else if(i
<75){//[73-74]
217 static const uint8_t crazy_mix_runlevel
[32]={
218 0x22,0x32,0x33,0x53,0x23,0x42,0x43,0x63,
219 0x24,0x52,0x34,0x73,0x25,0x62,0x44,0x83,
220 0x26,0x72,0x35,0x54,0x27,0x82,0x45,0x64,
221 0x28,0x92,0x36,0x74,0x29,0xa2,0x46,0x84};
224 e
=get_bits(&s
->gb
,5);//get the extra bits
225 (*run
) =crazy_mix_runlevel
[e
]>>4;
226 (*level
)=crazy_mix_runlevel
[e
]&0x0F;
228 (*level
)=get_bits( &s
->gb
, 7-3*(i
&1));
229 (*run
) =get_bits( &s
->gb
, 6);
230 (*final
)=get_bits1(&s
->gb
);
235 //static const uint8_t dc_extra_sbits[] ={0, 1,1, 1,1, 2,2, 3,3, 4,4, 5,5, 6,6, 7,7 };
236 static const uint8_t dc_index_offset
[] ={ 0, 1,2, 3,4, 5,7, 9,13, 17,25, 33,49, 65,97, 129,193};
238 static int x8_get_dc_rlf(IntraX8Context
* const w
,int const mode
, int * const level
, int * const final
){
239 MpegEncContext
* const s
= w
->s
;
243 if( !w
->j_dc_vlc
[mode
] ) {
245 table_index
= get_bits(&s
->gb
, 3);
246 //4 modes, same table
247 w
->j_dc_vlc
[mode
]= &j_dc_vlc
[w
->quant
<13][table_index
];
250 assert(w
->j_dc_vlc
[mode
]->table
);
252 i
=get_vlc2(&s
->gb
, w
->j_dc_vlc
[mode
]->table
, DC_VLC_BITS
, DC_VLC_MTD
);
254 /*(i>=17) {i-=17;final=1;}*/
263 c
=(i
+1)>>1;//hackish way to calculate dc_extra_sbits[]
266 e
=get_bits(&s
->gb
,c
);//get the extra bits
267 i
=dc_index_offset
[i
]+(e
>>1);
269 e
= -(e
& 1);//0,0xffffff
270 (*level
)= (i
^ e
) - e
;// (i^0)-0 , (i^0xff)-(-1)
275 static int x8_setup_spatial_predictor(IntraX8Context
* const w
, const int chroma
){
276 MpegEncContext
* const s
= w
->s
;
281 s
->dsp
.x8_setup_spatial_compensation(s
->dest
[chroma
], s
->edge_emu_buffer
,
282 s
->current_picture
.linesize
[chroma
>0],
283 &range
, &sum
, w
->edges
);
285 w
->orient
=w
->chroma_orient
;
286 quant
=w
->quant_dc_chroma
;
292 if(range
< quant
|| range
< 3){
294 if(range
< 3){//yep you read right, a +-1 idct error may break decoding!
297 w
->predicted_dc
= (sum
*6899)>>17;//((1<<17)+9)/(8+8+1+2)=6899
303 assert(w
->orient
< 3);
304 if(range
< 2*w
->quant
){
305 if( (w
->edges
&3) == 0){
306 if(w
->orient
==1) w
->orient
=11;
307 if(w
->orient
==2) w
->orient
=10;
313 static const uint8_t prediction_table
[3][12]={
314 {0,8,4, 10,11, 2,6,9,1,3,5,7},
315 {4,0,8, 11,10, 3,5,2,6,9,1,7},
316 {8,0,4, 10,11, 1,7,2,6,9,3,5}
318 w
->raw_orient
=x8_get_orient_vlc(w
);
319 if(w
->raw_orient
<0) return -1;
320 assert(w
->raw_orient
< 12 );
322 w
->orient
=prediction_table
[w
->orient
][w
->raw_orient
];
327 static void x8_update_predictions(IntraX8Context
* const w
, const int orient
, const int est_run
){
328 MpegEncContext
* const s
= w
->s
;
330 w
->prediction_table
[s
->mb_x
*2+(s
->mb_y
&1)] = (est_run
<<2) + 1*(orient
==4) + 2*(orient
==8);
336 static void x8_get_prediction_chroma(IntraX8Context
* const w
){
337 MpegEncContext
* const s
= w
->s
;
339 w
->edges
= 1*( !(s
->mb_x
>>1) );
340 w
->edges
|= 2*( !(s
->mb_y
>>1) );
341 w
->edges
|= 4*( s
->mb_x
>= (2*s
->mb_width
-1) );//mb_x for chroma would always be odd
344 if(w
->edges
&3){//lut_co[8]={inv,4,8,8, inv,4,8,8}<- =>{1,1,0,0;1,1,0,0} => 0xCC
345 w
->chroma_orient
=4<<((0xCC>>w
->edges
)&1);
348 w
->chroma_orient
= (w
->prediction_table
[2*s
->mb_x
-2] & 0x03)<<2;//block[x-1][y|1-1)]
351 static void x8_get_prediction(IntraX8Context
* const w
){
352 MpegEncContext
* const s
= w
->s
;
355 w
->edges
= 1*( !s
->mb_x
);
356 w
->edges
|= 2*( !s
->mb_y
);
357 w
->edges
|= 4*( s
->mb_x
>= (2*s
->mb_width
-1) );
363 //take the one from the above block[0][y-1]
364 w
->est_run
= w
->prediction_table
[!(s
->mb_y
&1)]>>2;
368 //take the one from the previous block[x-1][0]
369 w
->est_run
= w
->prediction_table
[2*s
->mb_x
-2]>>2;
378 b
= w
->prediction_table
[2*s
->mb_x
+ !(s
->mb_y
&1) ];//block[x ][y-1]
379 a
= w
->prediction_table
[2*s
->mb_x
-2 + (s
->mb_y
&1) ];//block[x-1][y ]
380 c
= w
->prediction_table
[2*s
->mb_x
-2 + !(s
->mb_y
&1) ];//block[x-1][y-1]
382 w
->est_run
= FFMIN(b
,a
);
383 /* This condition has nothing to do with w->edges, even if it looks
384 similar it would trigger if e.g. x=3;y=2;
385 I guess somebody wrote something wrong and it became standard. */
386 if( (s
->mb_x
& s
->mb_y
) != 0 ) w
->est_run
=FFMIN(c
,w
->est_run
);
393 i
=( 0xFFEAF4C4>>(2*b
+8*a
) )&3;
394 if(i
!=3) w
->orient
=i
;
395 else w
->orient
=( 0xFFEAD8>>(2*c
+8*(w
->quant
>12)) )&3;
401 pad 2 2 2; pad X 1 0; pad 0 1 0 <-
402 -> 11 10 '10 10 '11 11'01 00 '11 00'01 00=>0xEAF4C4
407 pad 2 2 2; pad 1 2 0 <-
408 -> 11 10'10 10 '11 01'10 00=>0xEAD8
413 static void x8_ac_compensation(IntraX8Context
* const w
, int const direction
, int const dc_level
){
414 MpegEncContext
* const s
= w
->s
;
416 #define B(x,y) s->block[0][s->dsp.idct_permutation[(x)+(y)*8]]
417 #define T(x) ((x) * dc_level + 0x8000) >> 16;
460 s
->block_last_index
[0] = FFMAX(s
->block_last_index
[0], 7*8);
468 s
->block_last_index
[0] = FFMAX(s
->block_last_index
[0], 7*8);
476 s
->block_last_index
[0] = FFMAX(s
->block_last_index
[0], 7);
483 static void dsp_x8_put_solidcolor(uint8_t const pix
, uint8_t * dst
, int const linesize
){
491 static const int16_t quant_table
[64] = {
492 256, 256, 256, 256, 256, 256, 259, 262,
493 265, 269, 272, 275, 278, 282, 285, 288,
494 292, 295, 299, 303, 306, 310, 314, 317,
495 321, 325, 329, 333, 337, 341, 345, 349,
496 353, 358, 362, 366, 371, 375, 379, 384,
497 389, 393, 398, 403, 408, 413, 417, 422,
498 428, 433, 438, 443, 448, 454, 459, 465,
499 470, 476, 482, 488, 493, 499, 505, 511
502 static int x8_decode_intra_mb(IntraX8Context
* const w
, const int chroma
){
503 MpegEncContext
* const s
= w
->s
;
507 int ac_mode
,dc_mode
,est_run
,dc_level
;
510 int use_quant_matrix
;
513 assert(w
->orient
<12);
514 memset(s
->block
[0],0x00,64*sizeof(DCTELEM
));
519 dc_mode
=!!w
->est_run
;//0,1
522 if(x8_get_dc_rlf(w
, dc_mode
, &dc_level
, &final
)) return -1;
525 if(!final
){//decode ac
526 use_quant_matrix
=w
->use_quant_matrix
;
529 est_run
= 64;//not used
531 if (w
->raw_orient
< 3){
532 use_quant_matrix
= 0;
534 if(w
->raw_orient
> 4){
547 x8_select_ac_table(w
,ac_mode
);
548 /*scantable_selector[12]={0,2,0,1,1,1,0,2,2,0,1,2};<-
549 -> 10'01' 00'10' 10'00' 01'01' 01'00' 10'00 =>0x928548 */
550 scantable
= w
->scantable
[ (0x928548>>(2*w
->orient
))&3 ].permutated
;
556 x8_select_ac_table(w
,3);
559 x8_get_ac_rlf(w
,ac_mode
,&run
,&level
,&final
);
563 //this also handles vlc error in x8_get_ac_rlf
566 level
= (level
+1) * w
->dquant
;
569 sign
= - get_bits1(&s
->gb
);
570 level
= (level
^ sign
) - sign
;
572 if(use_quant_matrix
){
573 level
= (level
*quant_table
[pos
])>>8;
575 s
->block
[0][ scantable
[pos
] ]=level
;
578 s
->block_last_index
[0]=pos
;
580 s
->block_last_index
[0]=0;
581 if(w
->flat_dc
&& ((unsigned)(dc_level
+1)) < 3){//[-1;1]
582 int32_t divide_quant
= !chroma
? w
->divide_quant_dc_luma
:
583 w
->divide_quant_dc_chroma
;
584 int32_t dc_quant
= !chroma
? w
->quant
:
587 //original intent dc_level+=predicted_dc/quant; but it got lost somewhere in the rounding
588 dc_level
+= (w
->predicted_dc
*divide_quant
+ (1<<12) )>>13;
590 dsp_x8_put_solidcolor( av_clip_uint8((dc_level
*dc_quant
+4)>>3),
591 s
->dest
[chroma
], s
->current_picture
.linesize
[!!chroma
]);
595 zeros_only
= (dc_level
== 0);
598 s
->block
[0][0] = dc_level
*w
->quant
;
600 s
->block
[0][0] = dc_level
*w
->quant_dc_chroma
;
603 //there is !zero_only check in the original, but dc_level check is enough
604 if( (unsigned int)(dc_level
+1) >= 3 && (w
->edges
&3) != 3 ){
606 /*ac_comp_direction[orient] = { 0, 3, 3, 1, 1, 0, 0, 0, 2, 2, 2, 1 };<-
607 -> 01'10' 10'10' 00'00' 00'01' 01'11' 11'00 =>0x6A017C */
608 direction
= (0x6A017C>>(w
->orient
*2))&3;
610 x8_ac_compensation(w
, direction
, s
->block
[0][0]);//modify block_last[]
615 dsp_x8_put_solidcolor(w
->predicted_dc
, s
->dest
[chroma
], s
->current_picture
.linesize
[!!chroma
]);
617 s
->dsp
.x8_spatial_compensation
[w
->orient
]( s
->edge_emu_buffer
,
619 s
->current_picture
.linesize
[!!chroma
] );
622 s
->dsp
.idct_add ( s
->dest
[chroma
],
623 s
->current_picture
.linesize
[!!chroma
],
629 x8_update_predictions(w
,w
->orient
,n
);
633 uint8_t* ptr
= s
->dest
[chroma
];
634 int linesize
= s
->current_picture
.linesize
[!!chroma
];
636 if(!( (w
->edges
&2) || ( zeros_only
&& (w
->orient
|4)==4 ) )){
637 s
->dsp
.x8_h_loop_filter(ptr
, linesize
, w
->quant
);
639 if(!( (w
->edges
&1) || ( zeros_only
&& (w
->orient
|8)==8 ) )){
640 s
->dsp
.x8_v_loop_filter(ptr
, linesize
, w
->quant
);
646 static void x8_init_block_index(MpegEncContext
*s
){ //FIXME maybe merge with ff_*
647 //not s->linesize as this would be wrong for field pics
648 //not that IntraX8 has interlacing support ;)
649 const int linesize
= s
->current_picture
.linesize
[0];
650 const int uvlinesize
= s
->current_picture
.linesize
[1];
652 s
->dest
[0] = s
->current_picture
.data
[0];
653 s
->dest
[1] = s
->current_picture
.data
[1];
654 s
->dest
[2] = s
->current_picture
.data
[2];
656 s
->dest
[0] += s
->mb_y
* linesize
<< 3;
657 s
->dest
[1] += ( s
->mb_y
&(~1) ) * uvlinesize
<< 2;//chroma blocks are on add rows
658 s
->dest
[2] += ( s
->mb_y
&(~1) ) * uvlinesize
<< 2;
662 * Initialize IntraX8 frame decoder.
663 * Requires valid MpegEncContext with valid s->mb_width before calling.
664 * @param w pointer to IntraX8Context
665 * @param s pointer to MpegEncContext of the parent codec
667 void ff_intrax8_common_init(IntraX8Context
* w
, MpegEncContext
* const s
){
671 assert(s
->mb_width
>0);
672 w
->prediction_table
=av_mallocz(s
->mb_width
*2*2);//two rows, 2 blocks per cannon mb
674 ff_init_scantable(s
->dsp
.idct_permutation
, &w
->scantable
[0], wmv1_scantable
[0]);
675 ff_init_scantable(s
->dsp
.idct_permutation
, &w
->scantable
[1], wmv1_scantable
[2]);
676 ff_init_scantable(s
->dsp
.idct_permutation
, &w
->scantable
[2], wmv1_scantable
[3]);
680 * Destroy IntraX8 frame structure.
681 * @param w pointer to IntraX8Context
683 void ff_intrax8_common_end(IntraX8Context
* w
)
685 av_freep(&w
->prediction_table
);
689 * Decode single IntraX8 frame.
690 * The parent codec must fill s->loopfilter and s->gb (bitstream).
691 * The parent codec must call MPV_frame_start(), ff_er_frame_start() before calling this function.
692 * The parent codec must call ff_er_frame_end(), MPV_frame_end() after calling this function.
693 * This function does not use MPV_decode_mb().
694 * lowres decoding is theoretically impossible.
695 * @param w pointer to IntraX8Context
696 * @param dquant doubled quantizer, it would be odd in case of VC-1 halfpq==1.
697 * @param quant_offset offset away from zero
699 //FIXME extern uint8_t wmv3_dc_scale_table[32];
700 int ff_intrax8_decode_picture(IntraX8Context
* const w
, int dquant
, int quant_offset
){
701 MpegEncContext
* const s
= w
->s
;
704 w
->use_quant_matrix
= get_bits1(&s
->gb
);
707 w
->quant
= dquant
>> 1;
708 w
->qsum
= quant_offset
;
710 w
->divide_quant_dc_luma
= ((1<<16) + (w
->quant
>>1)) / w
->quant
;
712 w
->quant_dc_chroma
= w
->quant
;
713 w
->divide_quant_dc_chroma
= w
->divide_quant_dc_luma
;
715 w
->quant_dc_chroma
= w
->quant
+((w
->quant
+3)>>3);
716 w
->divide_quant_dc_chroma
= ((1<<16) + (w
->quant_dc_chroma
>>1)) / w
->quant_dc_chroma
;
718 x8_reset_vlc_tables(w
);
723 for(s
->mb_y
=0; s
->mb_y
< s
->mb_height
*2; s
->mb_y
++){
724 x8_init_block_index(s
);
725 mb_xy
=(s
->mb_y
>>1)*s
->mb_stride
;
727 for(s
->mb_x
=0; s
->mb_x
< s
->mb_width
*2; s
->mb_x
++){
728 x8_get_prediction(w
);
729 if(x8_setup_spatial_predictor(w
,0)) goto error
;
730 if(x8_decode_intra_mb(w
,0)) goto error
;
732 if( s
->mb_x
& s
->mb_y
& 1 ){
733 x8_get_prediction_chroma(w
);
735 /*when setting up chroma, no vlc is read,
736 so no error condition can be reached*/
737 x8_setup_spatial_predictor(w
,1);
738 if(x8_decode_intra_mb(w
,1)) goto error
;
740 x8_setup_spatial_predictor(w
,2);
741 if(x8_decode_intra_mb(w
,2)) goto error
;
746 /*emulate MB info in the relevant tables*/
747 s
->mbskip_table
[mb_xy
]=0;
748 s
->mbintra_table
[mb_xy
]=1;
749 s
->current_picture
.qscale_table
[mb_xy
]=w
->quant
;
755 ff_draw_horiz_band(s
, (s
->mb_y
-1)*8, 16);
760 ff_er_add_slice(s
, s
->resync_mb_x
, s
->resync_mb_y
,
761 (s
->mb_x
>>1)-1, (s
->mb_y
>>1)-1,
762 (AC_END
|DC_END
|MV_END
) );