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
24 #include "libavutil/avassert.h"
26 #include "error_resilience.h"
28 #include "mpegvideo.h"
29 #include "msmpeg4data.h"
30 #include "intrax8huf.h"
32 #include "intrax8dsp.h"
34 #define MAX_TABLE_DEPTH(table_bits, max_bits) ((max_bits+table_bits-1)/table_bits)
40 #define DC_VLC_MTD MAX_TABLE_DEPTH(DC_VLC_BITS, MAX_DC_VLC_BITS)
41 #define AC_VLC_MTD MAX_TABLE_DEPTH(AC_VLC_BITS, MAX_AC_VLC_BITS)
42 #define OR_VLC_MTD MAX_TABLE_DEPTH(OR_VLC_BITS, MAX_OR_VLC_BITS)
44 static VLC j_ac_vlc[2][2][8]; //[quant<13],[intra/inter],[select]
45 static VLC j_dc_vlc[2][8]; //[quant], [select]
46 static VLC j_orient_vlc[2][4]; //[quant], [select]
48 static av_cold void x8_vlc_init(void){
52 static const uint16_t sizes[8*4 + 8*2 + 2 + 4] = {
53 576, 548, 582, 618, 546, 616, 560, 642,
54 584, 582, 704, 664, 512, 544, 656, 640,
55 512, 648, 582, 566, 532, 614, 596, 648,
56 586, 552, 584, 590, 544, 578, 584, 624,
58 528, 528, 526, 528, 536, 528, 526, 544,
59 544, 512, 512, 528, 528, 544, 512, 544,
61 128, 128, 128, 128, 128, 128};
63 static VLC_TYPE table[28150][2];
65 #define init_ac_vlc(dst,src) \
66 dst.table = &table[offset]; \
67 dst.table_allocated = sizes[sizeidx]; \
68 offset += sizes[sizeidx++]; \
73 INIT_VLC_USE_NEW_STATIC)
76 init_ac_vlc( j_ac_vlc[0][0][i], x8_ac0_highquant_table[i][0] );
77 init_ac_vlc( j_ac_vlc[0][1][i], x8_ac1_highquant_table[i][0] );
78 init_ac_vlc( j_ac_vlc[1][0][i], x8_ac0_lowquant_table [i][0] );
79 init_ac_vlc( j_ac_vlc[1][1][i], x8_ac1_lowquant_table [i][0] );
84 #define init_dc_vlc(dst,src) \
85 dst.table = &table[offset]; \
86 dst.table_allocated = sizes[sizeidx]; \
87 offset += sizes[sizeidx++]; \
92 INIT_VLC_USE_NEW_STATIC);
94 init_dc_vlc( j_dc_vlc[0][i], x8_dc_highquant_table[i][0]);
95 init_dc_vlc( j_dc_vlc[1][i], x8_dc_lowquant_table [i][0]);
100 #define init_or_vlc(dst,src) \
101 dst.table = &table[offset]; \
102 dst.table_allocated = sizes[sizeidx]; \
103 offset += sizes[sizeidx++]; \
108 INIT_VLC_USE_NEW_STATIC);
110 init_or_vlc( j_orient_vlc[0][i], x8_orient_highquant_table[i][0]);
113 init_or_vlc( j_orient_vlc[1][i], x8_orient_lowquant_table [i][0])
115 if (offset != sizeof(table)/sizeof(VLC_TYPE)/2)
116 av_log(NULL, AV_LOG_ERROR, "table size %i does not match needed %i\n", (int)(sizeof(table)/sizeof(VLC_TYPE)/2), offset);
120 static void x8_reset_vlc_tables(IntraX8Context * w){
121 memset(w->j_dc_vlc,0,sizeof(w->j_dc_vlc));
122 memset(w->j_ac_vlc,0,sizeof(w->j_ac_vlc));
123 w->j_orient_vlc=NULL;
126 static inline void x8_select_ac_table(IntraX8Context * const w , int mode){
127 MpegEncContext * const s= w->s;
132 if( w->j_ac_vlc[mode] ) return;
134 table_index = get_bits(&s->gb, 3);
135 w->j_ac_vlc[mode] = &j_ac_vlc[w->quant<13][mode>>1][table_index];//2 modes use same tables
136 av_assert2(w->j_ac_vlc[mode]);
139 static inline int x8_get_orient_vlc(IntraX8Context * w){
140 MpegEncContext * const s= w->s;
143 if(!w->j_orient_vlc ){
144 table_index = get_bits(&s->gb, 1+(w->quant<13) );
145 w->j_orient_vlc = &j_orient_vlc[w->quant<13][table_index];
148 return get_vlc2(&s->gb, w->j_orient_vlc->table, OR_VLC_BITS, OR_VLC_MTD);
151 #define extra_bits(eb) (eb)
152 #define extra_run (0xFF<<8)
153 #define extra_level (0x00<<8)
154 #define run_offset(r) ((r)<<16)
155 #define level_offset(l) ((l)<<24)
156 static const uint32_t ac_decode_table[]={
157 /*46*/ extra_bits(3) | extra_run | run_offset(16) | level_offset( 0),
158 /*47*/ extra_bits(3) | extra_run | run_offset(24) | level_offset( 0),
159 /*48*/ extra_bits(2) | extra_run | run_offset( 4) | level_offset( 1),
160 /*49*/ extra_bits(3) | extra_run | run_offset( 8) | level_offset( 1),
162 /*50*/ extra_bits(5) | extra_run | run_offset(32) | level_offset( 0),
163 /*51*/ extra_bits(4) | extra_run | run_offset(16) | level_offset( 1),
165 /*52*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset( 4),
166 /*53*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset( 8),
167 /*54*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset(12),
168 /*55*/ extra_bits(3) | extra_level | run_offset( 0) | level_offset(16),
169 /*56*/ extra_bits(3) | extra_level | run_offset( 0) | level_offset(24),
171 /*57*/ extra_bits(2) | extra_level | run_offset( 1) | level_offset( 3),
172 /*58*/ extra_bits(3) | extra_level | run_offset( 1) | level_offset( 7),
174 /*59*/ extra_bits(2) | extra_run | run_offset(16) | level_offset( 0),
175 /*60*/ extra_bits(2) | extra_run | run_offset(20) | level_offset( 0),
176 /*61*/ extra_bits(2) | extra_run | run_offset(24) | level_offset( 0),
177 /*62*/ extra_bits(2) | extra_run | run_offset(28) | level_offset( 0),
178 /*63*/ extra_bits(4) | extra_run | run_offset(32) | level_offset( 0),
179 /*64*/ extra_bits(4) | extra_run | run_offset(48) | level_offset( 0),
181 /*65*/ extra_bits(2) | extra_run | run_offset( 4) | level_offset( 1),
182 /*66*/ extra_bits(3) | extra_run | run_offset( 8) | level_offset( 1),
183 /*67*/ extra_bits(4) | extra_run | run_offset(16) | level_offset( 1),
185 /*68*/ extra_bits(2) | extra_level | run_offset( 0) | level_offset( 4),
186 /*69*/ extra_bits(3) | extra_level | run_offset( 0) | level_offset( 8),
187 /*70*/ extra_bits(4) | extra_level | run_offset( 0) | level_offset(16),
189 /*71*/ extra_bits(2) | extra_level | run_offset( 1) | level_offset( 3),
190 /*72*/ extra_bits(3) | extra_level | run_offset( 1) | level_offset( 7),
192 //extra_bits = 3bits; extra_run/level = 1 bit; run_offset = 6bits; level_offset = 5 bits;
199 static void x8_get_ac_rlf(IntraX8Context * const w, const int mode,
200 int * const run, int * const level, int * const final){
201 MpegEncContext * const s= w->s;
204 // x8_select_ac_table(w,mode);
205 i = get_vlc2(&s->gb, w->j_ac_vlc[mode]->table, AC_VLC_BITS, AC_VLC_MTD);
210 (*level)=(*final)=//prevent 'may be used unilitialized'
211 (*run)=64;//this would cause error exit in the ac loop
215 (*final) = t = (i>22);
218 i== 0-15 r=0-15 l=0 ;r=i& %01111
219 i==16-19 r=0-3 l=1 ;r=i& %00011
220 i==20-21 r=0-1 l=2 ;r=i& %00001
221 i==22 r=0 l=3 ;r=i& %00000
222 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
223 t=lut_mask[l]={0x0f,0x03,0x01,0x00}[l]; as i<256 the higher bits do not matter */
224 l=(0xE50000>>(i&(0x1E)))&3;/*0x1E or (~1) or ((i>>1)<<1)*/
225 t=(0x01030F>>(l<<3));
229 }else if(i<73){//[46-72]
234 sm=ac_decode_table[i];
236 e=get_bits(&s->gb,sm&0xF);sm>>=8;//3bits
237 mask=sm&0xff;sm>>=8; //1bit
239 (*run) =(sm&0xff) + (e&( mask));//6bits
240 (*level)=(sm>>8) + (e&(~mask));//5bits
242 }else if(i<75){//[73-74]
243 static const uint8_t crazy_mix_runlevel[32]={
244 0x22,0x32,0x33,0x53,0x23,0x42,0x43,0x63,
245 0x24,0x52,0x34,0x73,0x25,0x62,0x44,0x83,
246 0x26,0x72,0x35,0x54,0x27,0x82,0x45,0x64,
247 0x28,0x92,0x36,0x74,0x29,0xa2,0x46,0x84};
250 e=get_bits(&s->gb,5);//get the extra bits
251 (*run) =crazy_mix_runlevel[e]>>4;
252 (*level)=crazy_mix_runlevel[e]&0x0F;
254 (*level)=get_bits( &s->gb, 7-3*(i&1));
255 (*run) =get_bits( &s->gb, 6);
256 (*final)=get_bits1(&s->gb);
261 //static const uint8_t dc_extra_sbits[] ={0, 1,1, 1,1, 2,2, 3,3, 4,4, 5,5, 6,6, 7,7 };
262 static const uint8_t dc_index_offset[] ={ 0, 1,2, 3,4, 5,7, 9,13, 17,25, 33,49, 65,97, 129,193};
264 static int x8_get_dc_rlf(IntraX8Context * const w,int const mode, int * const level, int * const final){
265 MpegEncContext * const s= w->s;
269 if( !w->j_dc_vlc[mode] ) {
271 table_index = get_bits(&s->gb, 3);
272 //4 modes, same table
273 w->j_dc_vlc[mode]= &j_dc_vlc[w->quant<13][table_index];
276 i=get_vlc2(&s->gb, w->j_dc_vlc[mode]->table, DC_VLC_BITS, DC_VLC_MTD);
278 /*(i>=17) {i-=17;final=1;}*/
287 c=(i+1)>>1;//hackish way to calculate dc_extra_sbits[]
290 e=get_bits(&s->gb,c);//get the extra bits
291 i=dc_index_offset[i]+(e>>1);
293 e= -(e & 1);//0,0xffffff
294 (*level)= (i ^ e) - e;// (i^0)-0 , (i^0xff)-(-1)
299 static int x8_setup_spatial_predictor(IntraX8Context * const w, const int chroma){
300 MpegEncContext * const s= w->s;
305 w->dsp.setup_spatial_compensation(s->dest[chroma], s->edge_emu_buffer,
306 s->current_picture.f->linesize[chroma>0],
307 &range, &sum, w->edges);
309 w->orient=w->chroma_orient;
310 quant=w->quant_dc_chroma;
316 if(range < quant || range < 3){
318 if(range < 3){//yep you read right, a +-1 idct error may break decoding!
321 w->predicted_dc = (sum*6899)>>17;//((1<<17)+9)/(8+8+1+2)=6899
327 av_assert2(w->orient < 3);
328 if(range < 2*w->quant){
329 if( (w->edges&3) == 0){
330 if(w->orient==1) w->orient=11;
331 if(w->orient==2) w->orient=10;
337 static const uint8_t prediction_table[3][12]={
338 {0,8,4, 10,11, 2,6,9,1,3,5,7},
339 {4,0,8, 11,10, 3,5,2,6,9,1,7},
340 {8,0,4, 10,11, 1,7,2,6,9,3,5}
342 w->raw_orient=x8_get_orient_vlc(w);
343 if(w->raw_orient<0) return -1;
344 av_assert2(w->raw_orient < 12 );
345 av_assert2(w->orient<3);
346 w->orient=prediction_table[w->orient][w->raw_orient];
351 static void x8_update_predictions(IntraX8Context * const w, const int orient, const int est_run ){
352 MpegEncContext * const s= w->s;
354 w->prediction_table[s->mb_x*2+(s->mb_y&1)] = (est_run<<2) + 1*(orient==4) + 2*(orient==8);
360 static void x8_get_prediction_chroma(IntraX8Context * const w){
361 MpegEncContext * const s= w->s;
363 w->edges = 1*( !(s->mb_x>>1) );
364 w->edges|= 2*( !(s->mb_y>>1) );
365 w->edges|= 4*( s->mb_x >= (2*s->mb_width-1) );//mb_x for chroma would always be odd
368 if(w->edges&3){//lut_co[8]={inv,4,8,8, inv,4,8,8}<- =>{1,1,0,0;1,1,0,0} => 0xCC
369 w->chroma_orient=4<<((0xCC>>w->edges)&1);
372 w->chroma_orient = (w->prediction_table[2*s->mb_x-2] & 0x03)<<2;//block[x-1][y|1-1)]
375 static void x8_get_prediction(IntraX8Context * const w){
376 MpegEncContext * const s= w->s;
379 w->edges = 1*( !s->mb_x );
380 w->edges|= 2*( !s->mb_y );
381 w->edges|= 4*( s->mb_x >= (2*s->mb_width-1) );
387 //take the one from the above block[0][y-1]
388 w->est_run = w->prediction_table[!(s->mb_y&1)]>>2;
392 //take the one from the previous block[x-1][0]
393 w->est_run = w->prediction_table[2*s->mb_x-2]>>2;
402 b= w->prediction_table[2*s->mb_x + !(s->mb_y&1) ];//block[x ][y-1]
403 a= w->prediction_table[2*s->mb_x-2 + (s->mb_y&1) ];//block[x-1][y ]
404 c= w->prediction_table[2*s->mb_x-2 + !(s->mb_y&1) ];//block[x-1][y-1]
406 w->est_run = FFMIN(b,a);
407 /* This condition has nothing to do with w->edges, even if it looks
408 similar it would trigger if e.g. x=3;y=2;
409 I guess somebody wrote something wrong and it became standard. */
410 if( (s->mb_x & s->mb_y) != 0 ) w->est_run=FFMIN(c,w->est_run);
417 i=( 0xFFEAF4C4>>(2*b+8*a) )&3;
418 if(i!=3) w->orient=i;
419 else w->orient=( 0xFFEAD8>>(2*c+8*(w->quant>12)) )&3;
425 pad 2 2 2; pad X 1 0; pad 0 1 0 <-
426 -> 11 10 '10 10 '11 11'01 00 '11 00'01 00=>0xEAF4C4
431 pad 2 2 2; pad 1 2 0 <-
432 -> 11 10'10 10 '11 01'10 00=>0xEAD8
437 static void x8_ac_compensation(IntraX8Context * const w, int const direction, int const dc_level){
438 MpegEncContext * const s= w->s;
440 #define B(x,y) s->block[0][w->idct_permutation[(x)+(y)*8]]
441 #define T(x) ((x) * dc_level + 0x8000) >> 16;
484 s->block_last_index[0] = FFMAX(s->block_last_index[0], 7*8);
492 s->block_last_index[0] = FFMAX(s->block_last_index[0], 7*8);
500 s->block_last_index[0] = FFMAX(s->block_last_index[0], 7);
507 static void dsp_x8_put_solidcolor(uint8_t const pix, uint8_t * dst, int const linesize){
515 static const int16_t quant_table[64] = {
516 256, 256, 256, 256, 256, 256, 259, 262,
517 265, 269, 272, 275, 278, 282, 285, 288,
518 292, 295, 299, 303, 306, 310, 314, 317,
519 321, 325, 329, 333, 337, 341, 345, 349,
520 353, 358, 362, 366, 371, 375, 379, 384,
521 389, 393, 398, 403, 408, 413, 417, 422,
522 428, 433, 438, 443, 448, 454, 459, 465,
523 470, 476, 482, 488, 493, 499, 505, 511
526 static int x8_decode_intra_mb(IntraX8Context* const w, const int chroma){
527 MpegEncContext * const s= w->s;
531 int ac_mode,dc_mode,est_run,dc_level;
534 int use_quant_matrix;
537 av_assert2(w->orient<12);
538 s->dsp.clear_block(s->block[0]);
543 dc_mode=!!w->est_run;//0,1
546 if(x8_get_dc_rlf(w, dc_mode, &dc_level, &final)) return -1;
549 if(!final){//decode ac
550 use_quant_matrix=w->use_quant_matrix;
553 est_run = 64;//not used
555 if (w->raw_orient < 3){
556 use_quant_matrix = 0;
558 if(w->raw_orient > 4){
571 x8_select_ac_table(w,ac_mode);
572 /*scantable_selector[12]={0,2,0,1,1,1,0,2,2,0,1,2};<-
573 -> 10'01' 00'10' 10'00' 01'01' 01'00' 10'00 =>0x928548 */
574 scantable = w->scantable[ (0x928548>>(2*w->orient))&3 ].permutated;
580 x8_select_ac_table(w,3);
583 x8_get_ac_rlf(w,ac_mode,&run,&level,&final);
587 //this also handles vlc error in x8_get_ac_rlf
590 level= (level+1) * w->dquant;
593 sign = - get_bits1(&s->gb);
594 level = (level ^ sign) - sign;
596 if(use_quant_matrix){
597 level = (level*quant_table[pos])>>8;
599 s->block[0][ scantable[pos] ]=level;
602 s->block_last_index[0]=pos;
604 s->block_last_index[0]=0;
605 if(w->flat_dc && ((unsigned)(dc_level+1)) < 3){//[-1;1]
606 int32_t divide_quant= !chroma ? w->divide_quant_dc_luma:
607 w->divide_quant_dc_chroma;
608 int32_t dc_quant = !chroma ? w->quant:
611 //original intent dc_level+=predicted_dc/quant; but it got lost somewhere in the rounding
612 dc_level+= (w->predicted_dc*divide_quant + (1<<12) )>>13;
614 dsp_x8_put_solidcolor( av_clip_uint8((dc_level*dc_quant+4)>>3),
615 s->dest[chroma], s->current_picture.f->linesize[!!chroma]);
619 zeros_only = (dc_level == 0);
622 s->block[0][0] = dc_level*w->quant;
624 s->block[0][0] = dc_level*w->quant_dc_chroma;
627 //there is !zero_only check in the original, but dc_level check is enough
628 if( (unsigned int)(dc_level+1) >= 3 && (w->edges&3) != 3 ){
630 /*ac_comp_direction[orient] = { 0, 3, 3, 1, 1, 0, 0, 0, 2, 2, 2, 1 };<-
631 -> 01'10' 10'10' 00'00' 00'01' 01'11' 11'00 =>0x6A017C */
632 direction= (0x6A017C>>(w->orient*2))&3;
634 x8_ac_compensation(w, direction, s->block[0][0]);//modify block_last[]
639 dsp_x8_put_solidcolor(w->predicted_dc, s->dest[chroma], s->current_picture.f->linesize[!!chroma]);
641 w->dsp.spatial_compensation[w->orient]( s->edge_emu_buffer,
643 s->current_picture.f->linesize[!!chroma] );
646 w->wdsp.idct_add (s->dest[chroma],
647 s->current_picture.f->linesize[!!chroma],
653 x8_update_predictions(w,w->orient,n);
657 uint8_t* ptr = s->dest[chroma];
658 int linesize = s->current_picture.f->linesize[!!chroma];
660 if(!( (w->edges&2) || ( zeros_only && (w->orient|4)==4 ) )){
661 w->dsp.h_loop_filter(ptr, linesize, w->quant);
663 if(!( (w->edges&1) || ( zeros_only && (w->orient|8)==8 ) )){
664 w->dsp.v_loop_filter(ptr, linesize, w->quant);
670 static void x8_init_block_index(MpegEncContext *s){ //FIXME maybe merge with ff_*
671 //not s->linesize as this would be wrong for field pics
672 //not that IntraX8 has interlacing support ;)
673 const int linesize = s->current_picture.f->linesize[0];
674 const int uvlinesize = s->current_picture.f->linesize[1];
676 s->dest[0] = s->current_picture.f->data[0];
677 s->dest[1] = s->current_picture.f->data[1];
678 s->dest[2] = s->current_picture.f->data[2];
680 s->dest[0] += s->mb_y * linesize << 3;
681 s->dest[1] += ( s->mb_y&(~1) ) * uvlinesize << 2;//chroma blocks are on add rows
682 s->dest[2] += ( s->mb_y&(~1) ) * uvlinesize << 2;
686 * Initialize IntraX8 frame decoder.
687 * Requires valid MpegEncContext with valid s->mb_width before calling.
688 * @param w pointer to IntraX8Context
689 * @param s pointer to MpegEncContext of the parent codec
691 av_cold void ff_intrax8_common_init(IntraX8Context * w, MpegEncContext * const s){
695 av_assert0(s->mb_width>0);
696 w->prediction_table=av_mallocz(s->mb_width*2*2);//two rows, 2 blocks per cannon mb
698 ff_wmv2dsp_init(&w->wdsp);
699 ff_init_scantable_permutation(w->idct_permutation,
702 ff_init_scantable(w->idct_permutation, &w->scantable[0], ff_wmv1_scantable[0]);
703 ff_init_scantable(w->idct_permutation, &w->scantable[1], ff_wmv1_scantable[2]);
704 ff_init_scantable(w->idct_permutation, &w->scantable[2], ff_wmv1_scantable[3]);
706 ff_intrax8dsp_init(&w->dsp);
710 * Destroy IntraX8 frame structure.
711 * @param w pointer to IntraX8Context
713 av_cold void ff_intrax8_common_end(IntraX8Context * w)
715 av_freep(&w->prediction_table);
719 * Decode single IntraX8 frame.
720 * The parent codec must fill s->loopfilter and s->gb (bitstream).
721 * The parent codec must call MPV_frame_start(), ff_er_frame_start() before calling this function.
722 * The parent codec must call ff_er_frame_end(), MPV_frame_end() after calling this function.
723 * This function does not use MPV_decode_mb().
724 * lowres decoding is theoretically impossible.
725 * @param w pointer to IntraX8Context
726 * @param dquant doubled quantizer, it would be odd in case of VC-1 halfpq==1.
727 * @param quant_offset offset away from zero
729 int ff_intrax8_decode_picture(IntraX8Context * const w, int dquant, int quant_offset){
730 MpegEncContext * const s= w->s;
732 w->use_quant_matrix = get_bits1(&s->gb);
735 w->quant = dquant >> 1;
736 w->qsum = quant_offset;
738 w->divide_quant_dc_luma = ((1<<16) + (w->quant>>1)) / w->quant;
740 w->quant_dc_chroma = w->quant;
741 w->divide_quant_dc_chroma = w->divide_quant_dc_luma;
743 w->quant_dc_chroma = w->quant+((w->quant+3)>>3);
744 w->divide_quant_dc_chroma = ((1<<16) + (w->quant_dc_chroma>>1)) / w->quant_dc_chroma;
746 x8_reset_vlc_tables(w);
751 for(s->mb_y=0; s->mb_y < s->mb_height*2; s->mb_y++){
752 x8_init_block_index(s);
753 mb_xy=(s->mb_y>>1)*s->mb_stride;
755 for(s->mb_x=0; s->mb_x < s->mb_width*2; s->mb_x++){
756 x8_get_prediction(w);
757 if(x8_setup_spatial_predictor(w,0)) goto error;
758 if(x8_decode_intra_mb(w,0)) goto error;
760 if( s->mb_x & s->mb_y & 1 ){
761 x8_get_prediction_chroma(w);
763 /*when setting up chroma, no vlc is read,
764 so no error condition can be reached*/
765 x8_setup_spatial_predictor(w,1);
766 if(x8_decode_intra_mb(w,1)) goto error;
768 x8_setup_spatial_predictor(w,2);
769 if(x8_decode_intra_mb(w,2)) goto error;
774 /*emulate MB info in the relevant tables*/
775 s->mbskip_table [mb_xy]=0;
776 s->mbintra_table[mb_xy]=1;
777 s->current_picture.qscale_table[mb_xy] = w->quant;
783 ff_mpeg_draw_horiz_band(s, (s->mb_y-1)*8, 16);
788 ff_er_add_slice(&s->er, s->resync_mb_x, s->resync_mb_y,
789 (s->mb_x>>1)-1, (s->mb_y>>1)-1,