check for request_channels at codec init
[ffmpeg-lucabe.git] / libavcodec / mpeg12.c
blob5b006c3c0f5289d69793666fb2cf64d43b32a844
1 /*
2 * MPEG1/2 decoder
3 * Copyright (c) 2000,2001 Fabrice Bellard.
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 /**
24 * @file mpeg12.c
25 * MPEG1/2 decoder
28 //#define DEBUG
29 #include "avcodec.h"
30 #include "dsputil.h"
31 #include "mpegvideo.h"
33 #include "mpeg12.h"
34 #include "mpeg12data.h"
35 #include "mpeg12decdata.h"
36 #include "bytestream.h"
38 //#undef NDEBUG
39 //#include <assert.h>
42 #define DC_VLC_BITS 9
43 #define MV_VLC_BITS 9
44 #define MBINCR_VLC_BITS 9
45 #define MB_PAT_VLC_BITS 9
46 #define MB_PTYPE_VLC_BITS 6
47 #define MB_BTYPE_VLC_BITS 6
48 #define TEX_VLC_BITS 9
50 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
51 DCTELEM *block,
52 int n);
53 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
54 DCTELEM *block,
55 int n);
56 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n);
57 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
58 DCTELEM *block,
59 int n);
60 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
61 DCTELEM *block,
62 int n);
63 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s, DCTELEM *block, int n);
64 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
65 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
66 static void exchange_uv(MpegEncContext *s);
68 extern int XVMC_field_start(MpegEncContext *s, AVCodecContext *avctx);
69 extern int XVMC_field_end(MpegEncContext *s);
70 extern void XVMC_pack_pblocks(MpegEncContext *s,int cbp);
71 extern void XVMC_init_block(MpegEncContext *s);//set s->block
73 static const enum PixelFormat pixfmt_yuv_420[]= {PIX_FMT_YUV420P,-1};
74 static const enum PixelFormat pixfmt_yuv_422[]= {PIX_FMT_YUV422P,-1};
75 static const enum PixelFormat pixfmt_yuv_444[]= {PIX_FMT_YUV444P,-1};
76 static const enum PixelFormat pixfmt_xvmc_mpg2_420[] = {
77 PIX_FMT_XVMC_MPEG2_IDCT,
78 PIX_FMT_XVMC_MPEG2_MC,
79 -1};
81 uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
83 static void init_2d_vlc_rl(RLTable *rl, int use_static)
85 int i;
87 init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2,
88 &rl->table_vlc[0][1], 4, 2,
89 &rl->table_vlc[0][0], 4, 2, use_static);
91 if(use_static)
92 rl->rl_vlc[0]= av_mallocz_static(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
93 else
94 rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
96 for(i=0; i<rl->vlc.table_size; i++){
97 int code= rl->vlc.table[i][0];
98 int len = rl->vlc.table[i][1];
99 int level, run;
101 if(len==0){ // illegal code
102 run= 65;
103 level= MAX_LEVEL;
104 }else if(len<0){ //more bits needed
105 run= 0;
106 level= code;
107 }else{
108 if(code==rl->n){ //esc
109 run= 65;
110 level= 0;
111 }else if(code==rl->n+1){ //eob
112 run= 0;
113 level= 127;
114 }else{
115 run= rl->table_run [code] + 1;
116 level= rl->table_level[code];
119 rl->rl_vlc[0][i].len= len;
120 rl->rl_vlc[0][i].level= level;
121 rl->rl_vlc[0][i].run= run;
125 void ff_mpeg12_common_init(MpegEncContext *s)
128 s->y_dc_scale_table=
129 s->c_dc_scale_table= mpeg2_dc_scale_table[s->intra_dc_precision];
133 void ff_mpeg1_clean_buffers(MpegEncContext *s){
134 s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
135 s->last_dc[1] = s->last_dc[0];
136 s->last_dc[2] = s->last_dc[0];
137 memset(s->last_mv, 0, sizeof(s->last_mv));
141 /******************************************/
142 /* decoding */
144 static VLC dc_lum_vlc;
145 static VLC dc_chroma_vlc;
146 static VLC mv_vlc;
147 static VLC mbincr_vlc;
148 static VLC mb_ptype_vlc;
149 static VLC mb_btype_vlc;
150 static VLC mb_pat_vlc;
152 static void init_vlcs(void)
154 static int done = 0;
156 if (!done) {
157 done = 1;
159 init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12,
160 ff_mpeg12_vlc_dc_lum_bits, 1, 1,
161 ff_mpeg12_vlc_dc_lum_code, 2, 2, 1);
162 init_vlc(&dc_chroma_vlc, DC_VLC_BITS, 12,
163 ff_mpeg12_vlc_dc_chroma_bits, 1, 1,
164 ff_mpeg12_vlc_dc_chroma_code, 2, 2, 1);
165 init_vlc(&mv_vlc, MV_VLC_BITS, 17,
166 &ff_mpeg12_mbMotionVectorTable[0][1], 2, 1,
167 &ff_mpeg12_mbMotionVectorTable[0][0], 2, 1, 1);
168 init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 36,
169 &ff_mpeg12_mbAddrIncrTable[0][1], 2, 1,
170 &ff_mpeg12_mbAddrIncrTable[0][0], 2, 1, 1);
171 init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 64,
172 &ff_mpeg12_mbPatTable[0][1], 2, 1,
173 &ff_mpeg12_mbPatTable[0][0], 2, 1, 1);
175 init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 7,
176 &table_mb_ptype[0][1], 2, 1,
177 &table_mb_ptype[0][0], 2, 1, 1);
178 init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 11,
179 &table_mb_btype[0][1], 2, 1,
180 &table_mb_btype[0][0], 2, 1, 1);
181 init_rl(&ff_rl_mpeg1, ff_mpeg12_static_rl_table_store[0]);
182 init_rl(&ff_rl_mpeg2, ff_mpeg12_static_rl_table_store[1]);
184 init_2d_vlc_rl(&ff_rl_mpeg1, 1);
185 init_2d_vlc_rl(&ff_rl_mpeg2, 1);
189 static inline int get_dmv(MpegEncContext *s)
191 if(get_bits1(&s->gb))
192 return 1 - (get_bits1(&s->gb) << 1);
193 else
194 return 0;
197 static inline int get_qscale(MpegEncContext *s)
199 int qscale = get_bits(&s->gb, 5);
200 if (s->q_scale_type) {
201 return non_linear_qscale[qscale];
202 } else {
203 return qscale << 1;
207 /* motion type (for mpeg2) */
208 #define MT_FIELD 1
209 #define MT_FRAME 2
210 #define MT_16X8 2
211 #define MT_DMV 3
213 static int mpeg_decode_mb(MpegEncContext *s,
214 DCTELEM block[12][64])
216 int i, j, k, cbp, val, mb_type, motion_type;
217 const int mb_block_count = 4 + (1<< s->chroma_format);
219 dprintf(s->avctx, "decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
221 assert(s->mb_skipped==0);
223 if (s->mb_skip_run-- != 0) {
224 if (s->pict_type == P_TYPE) {
225 s->mb_skipped = 1;
226 s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= MB_TYPE_SKIP | MB_TYPE_L0 | MB_TYPE_16x16;
227 } else {
228 int mb_type;
230 if(s->mb_x)
231 mb_type= s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1];
232 else
233 mb_type= s->current_picture.mb_type[ s->mb_width + (s->mb_y-1)*s->mb_stride - 1]; // FIXME not sure if this is allowed in mpeg at all,
234 if(IS_INTRA(mb_type))
235 return -1;
237 s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]=
238 mb_type | MB_TYPE_SKIP;
239 // assert(s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride - 1]&(MB_TYPE_16x16|MB_TYPE_16x8));
241 if((s->mv[0][0][0]|s->mv[0][0][1]|s->mv[1][0][0]|s->mv[1][0][1])==0)
242 s->mb_skipped = 1;
245 return 0;
248 switch(s->pict_type) {
249 default:
250 case I_TYPE:
251 if (get_bits1(&s->gb) == 0) {
252 if (get_bits1(&s->gb) == 0){
253 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in I Frame at %d %d\n", s->mb_x, s->mb_y);
254 return -1;
256 mb_type = MB_TYPE_QUANT | MB_TYPE_INTRA;
257 } else {
258 mb_type = MB_TYPE_INTRA;
260 break;
261 case P_TYPE:
262 mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
263 if (mb_type < 0){
264 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
265 return -1;
267 mb_type = ptype2mb_type[ mb_type ];
268 break;
269 case B_TYPE:
270 mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
271 if (mb_type < 0){
272 av_log(s->avctx, AV_LOG_ERROR, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
273 return -1;
275 mb_type = btype2mb_type[ mb_type ];
276 break;
278 dprintf(s->avctx, "mb_type=%x\n", mb_type);
279 // motion_type = 0; /* avoid warning */
280 if (IS_INTRA(mb_type)) {
281 s->dsp.clear_blocks(s->block[0]);
283 if(!s->chroma_y_shift){
284 s->dsp.clear_blocks(s->block[6]);
287 /* compute dct type */
288 if (s->picture_structure == PICT_FRAME && //FIXME add a interlaced_dct coded var?
289 !s->frame_pred_frame_dct) {
290 s->interlaced_dct = get_bits1(&s->gb);
293 if (IS_QUANT(mb_type))
294 s->qscale = get_qscale(s);
296 if (s->concealment_motion_vectors) {
297 /* just parse them */
298 if (s->picture_structure != PICT_FRAME)
299 skip_bits1(&s->gb); /* field select */
301 s->mv[0][0][0]= s->last_mv[0][0][0]= s->last_mv[0][1][0] =
302 mpeg_decode_motion(s, s->mpeg_f_code[0][0], s->last_mv[0][0][0]);
303 s->mv[0][0][1]= s->last_mv[0][0][1]= s->last_mv[0][1][1] =
304 mpeg_decode_motion(s, s->mpeg_f_code[0][1], s->last_mv[0][0][1]);
306 skip_bits1(&s->gb); /* marker */
307 }else
308 memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
309 s->mb_intra = 1;
310 #ifdef HAVE_XVMC
311 //one 1 we memcpy blocks in xvmcvideo
312 if(s->avctx->xvmc_acceleration > 1){
313 XVMC_pack_pblocks(s,-1);//inter are always full blocks
314 if(s->swap_uv){
315 exchange_uv(s);
318 #endif
320 if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
321 if(s->flags2 & CODEC_FLAG2_FAST){
322 for(i=0;i<6;i++) {
323 mpeg2_fast_decode_block_intra(s, s->pblocks[i], i);
325 }else{
326 for(i=0;i<mb_block_count;i++) {
327 if (mpeg2_decode_block_intra(s, s->pblocks[i], i) < 0)
328 return -1;
331 } else {
332 for(i=0;i<6;i++) {
333 if (mpeg1_decode_block_intra(s, s->pblocks[i], i) < 0)
334 return -1;
337 } else {
338 if (mb_type & MB_TYPE_ZERO_MV){
339 assert(mb_type & MB_TYPE_CBP);
341 s->mv_dir = MV_DIR_FORWARD;
342 if(s->picture_structure == PICT_FRAME){
343 if(!s->frame_pred_frame_dct)
344 s->interlaced_dct = get_bits1(&s->gb);
345 s->mv_type = MV_TYPE_16X16;
346 }else{
347 s->mv_type = MV_TYPE_FIELD;
348 mb_type |= MB_TYPE_INTERLACED;
349 s->field_select[0][0]= s->picture_structure - 1;
352 if (IS_QUANT(mb_type))
353 s->qscale = get_qscale(s);
355 s->last_mv[0][0][0] = 0;
356 s->last_mv[0][0][1] = 0;
357 s->last_mv[0][1][0] = 0;
358 s->last_mv[0][1][1] = 0;
359 s->mv[0][0][0] = 0;
360 s->mv[0][0][1] = 0;
361 }else{
362 assert(mb_type & MB_TYPE_L0L1);
363 //FIXME decide if MBs in field pictures are MB_TYPE_INTERLACED
364 /* get additional motion vector type */
365 if (s->frame_pred_frame_dct)
366 motion_type = MT_FRAME;
367 else{
368 motion_type = get_bits(&s->gb, 2);
369 if (s->picture_structure == PICT_FRAME && HAS_CBP(mb_type))
370 s->interlaced_dct = get_bits1(&s->gb);
373 if (IS_QUANT(mb_type))
374 s->qscale = get_qscale(s);
376 /* motion vectors */
377 s->mv_dir= (mb_type>>13)&3;
378 dprintf(s->avctx, "motion_type=%d\n", motion_type);
379 switch(motion_type) {
380 case MT_FRAME: /* or MT_16X8 */
381 if (s->picture_structure == PICT_FRAME) {
382 mb_type |= MB_TYPE_16x16;
383 s->mv_type = MV_TYPE_16X16;
384 for(i=0;i<2;i++) {
385 if (USES_LIST(mb_type, i)) {
386 /* MT_FRAME */
387 s->mv[i][0][0]= s->last_mv[i][0][0]= s->last_mv[i][1][0] =
388 mpeg_decode_motion(s, s->mpeg_f_code[i][0], s->last_mv[i][0][0]);
389 s->mv[i][0][1]= s->last_mv[i][0][1]= s->last_mv[i][1][1] =
390 mpeg_decode_motion(s, s->mpeg_f_code[i][1], s->last_mv[i][0][1]);
391 /* full_pel: only for mpeg1 */
392 if (s->full_pel[i]){
393 s->mv[i][0][0] <<= 1;
394 s->mv[i][0][1] <<= 1;
398 } else {
399 mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
400 s->mv_type = MV_TYPE_16X8;
401 for(i=0;i<2;i++) {
402 if (USES_LIST(mb_type, i)) {
403 /* MT_16X8 */
404 for(j=0;j<2;j++) {
405 s->field_select[i][j] = get_bits1(&s->gb);
406 for(k=0;k<2;k++) {
407 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
408 s->last_mv[i][j][k]);
409 s->last_mv[i][j][k] = val;
410 s->mv[i][j][k] = val;
416 break;
417 case MT_FIELD:
418 s->mv_type = MV_TYPE_FIELD;
419 if (s->picture_structure == PICT_FRAME) {
420 mb_type |= MB_TYPE_16x8 | MB_TYPE_INTERLACED;
421 for(i=0;i<2;i++) {
422 if (USES_LIST(mb_type, i)) {
423 for(j=0;j<2;j++) {
424 s->field_select[i][j] = get_bits1(&s->gb);
425 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
426 s->last_mv[i][j][0]);
427 s->last_mv[i][j][0] = val;
428 s->mv[i][j][0] = val;
429 dprintf(s->avctx, "fmx=%d\n", val);
430 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
431 s->last_mv[i][j][1] >> 1);
432 s->last_mv[i][j][1] = val << 1;
433 s->mv[i][j][1] = val;
434 dprintf(s->avctx, "fmy=%d\n", val);
438 } else {
439 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
440 for(i=0;i<2;i++) {
441 if (USES_LIST(mb_type, i)) {
442 s->field_select[i][0] = get_bits1(&s->gb);
443 for(k=0;k<2;k++) {
444 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
445 s->last_mv[i][0][k]);
446 s->last_mv[i][0][k] = val;
447 s->last_mv[i][1][k] = val;
448 s->mv[i][0][k] = val;
453 break;
454 case MT_DMV:
455 s->mv_type = MV_TYPE_DMV;
456 for(i=0;i<2;i++) {
457 if (USES_LIST(mb_type, i)) {
458 int dmx, dmy, mx, my, m;
459 mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
460 s->last_mv[i][0][0]);
461 s->last_mv[i][0][0] = mx;
462 s->last_mv[i][1][0] = mx;
463 dmx = get_dmv(s);
464 my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
465 s->last_mv[i][0][1] >> 1);
466 dmy = get_dmv(s);
469 s->last_mv[i][0][1] = my<<1;
470 s->last_mv[i][1][1] = my<<1;
472 s->mv[i][0][0] = mx;
473 s->mv[i][0][1] = my;
474 s->mv[i][1][0] = mx;//not used
475 s->mv[i][1][1] = my;//not used
477 if (s->picture_structure == PICT_FRAME) {
478 mb_type |= MB_TYPE_16x16 | MB_TYPE_INTERLACED;
480 //m = 1 + 2 * s->top_field_first;
481 m = s->top_field_first ? 1 : 3;
483 /* top -> top pred */
484 s->mv[i][2][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
485 s->mv[i][2][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
486 m = 4 - m;
487 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
488 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
489 } else {
490 mb_type |= MB_TYPE_16x16;
492 s->mv[i][2][0] = ((mx + (mx > 0)) >> 1) + dmx;
493 s->mv[i][2][1] = ((my + (my > 0)) >> 1) + dmy;
494 if(s->picture_structure == PICT_TOP_FIELD)
495 s->mv[i][2][1]--;
496 else
497 s->mv[i][2][1]++;
501 break;
502 default:
503 av_log(s->avctx, AV_LOG_ERROR, "00 motion_type at %d %d\n", s->mb_x, s->mb_y);
504 return -1;
508 s->mb_intra = 0;
509 if (HAS_CBP(mb_type)) {
510 s->dsp.clear_blocks(s->block[0]);
512 cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
513 if(mb_block_count > 6){
514 cbp<<= mb_block_count-6;
515 cbp |= get_bits(&s->gb, mb_block_count-6);
516 s->dsp.clear_blocks(s->block[6]);
518 if (cbp <= 0){
519 av_log(s->avctx, AV_LOG_ERROR, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
520 return -1;
523 #ifdef HAVE_XVMC
524 //on 1 we memcpy blocks in xvmcvideo
525 if(s->avctx->xvmc_acceleration > 1){
526 XVMC_pack_pblocks(s,cbp);
527 if(s->swap_uv){
528 exchange_uv(s);
531 #endif
533 if (s->codec_id == CODEC_ID_MPEG2VIDEO) {
534 if(s->flags2 & CODEC_FLAG2_FAST){
535 for(i=0;i<6;i++) {
536 if(cbp & 32) {
537 mpeg2_fast_decode_block_non_intra(s, s->pblocks[i], i);
538 } else {
539 s->block_last_index[i] = -1;
541 cbp+=cbp;
543 }else{
544 cbp<<= 12-mb_block_count;
546 for(i=0;i<mb_block_count;i++) {
547 if ( cbp & (1<<11) ) {
548 if (mpeg2_decode_block_non_intra(s, s->pblocks[i], i) < 0)
549 return -1;
550 } else {
551 s->block_last_index[i] = -1;
553 cbp+=cbp;
556 } else {
557 if(s->flags2 & CODEC_FLAG2_FAST){
558 for(i=0;i<6;i++) {
559 if (cbp & 32) {
560 mpeg1_fast_decode_block_inter(s, s->pblocks[i], i);
561 } else {
562 s->block_last_index[i] = -1;
564 cbp+=cbp;
566 }else{
567 for(i=0;i<6;i++) {
568 if (cbp & 32) {
569 if (mpeg1_decode_block_inter(s, s->pblocks[i], i) < 0)
570 return -1;
571 } else {
572 s->block_last_index[i] = -1;
574 cbp+=cbp;
578 }else{
579 for(i=0;i<12;i++)
580 s->block_last_index[i] = -1;
584 s->current_picture.mb_type[ s->mb_x + s->mb_y*s->mb_stride ]= mb_type;
586 return 0;
589 /* as h263, but only 17 codes */
590 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
592 int code, sign, val, l, shift;
594 code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
595 if (code == 0) {
596 return pred;
598 if (code < 0) {
599 return 0xffff;
602 sign = get_bits1(&s->gb);
603 shift = fcode - 1;
604 val = code;
605 if (shift) {
606 val = (val - 1) << shift;
607 val |= get_bits(&s->gb, shift);
608 val++;
610 if (sign)
611 val = -val;
612 val += pred;
614 /* modulo decoding */
615 l= INT_BIT - 5 - shift;
616 val = (val<<l)>>l;
617 return val;
620 static inline int decode_dc(GetBitContext *gb, int component)
622 int code, diff;
624 if (component == 0) {
625 code = get_vlc2(gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
626 } else {
627 code = get_vlc2(gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
629 if (code < 0){
630 av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
631 return 0xffff;
633 if (code == 0) {
634 diff = 0;
635 } else {
636 diff = get_xbits(gb, code);
638 return diff;
641 static inline int mpeg1_decode_block_intra(MpegEncContext *s,
642 DCTELEM *block,
643 int n)
645 int level, dc, diff, i, j, run;
646 int component;
647 RLTable *rl = &ff_rl_mpeg1;
648 uint8_t * const scantable= s->intra_scantable.permutated;
649 const uint16_t *quant_matrix= s->intra_matrix;
650 const int qscale= s->qscale;
652 /* DC coef */
653 component = (n <= 3 ? 0 : n - 4 + 1);
654 diff = decode_dc(&s->gb, component);
655 if (diff >= 0xffff)
656 return -1;
657 dc = s->last_dc[component];
658 dc += diff;
659 s->last_dc[component] = dc;
660 block[0] = dc<<3;
661 dprintf(s->avctx, "dc=%d diff=%d\n", dc, diff);
662 i = 0;
664 OPEN_READER(re, &s->gb);
665 /* now quantify & encode AC coefs */
666 for(;;) {
667 UPDATE_CACHE(re, &s->gb);
668 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
670 if(level == 127){
671 break;
672 } else if(level != 0) {
673 i += run;
674 j = scantable[i];
675 level= (level*qscale*quant_matrix[j])>>4;
676 level= (level-1)|1;
677 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
678 LAST_SKIP_BITS(re, &s->gb, 1);
679 } else {
680 /* escape */
681 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
682 UPDATE_CACHE(re, &s->gb);
683 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
684 if (level == -128) {
685 level = SHOW_UBITS(re, &s->gb, 8) - 256; LAST_SKIP_BITS(re, &s->gb, 8);
686 } else if (level == 0) {
687 level = SHOW_UBITS(re, &s->gb, 8) ; LAST_SKIP_BITS(re, &s->gb, 8);
689 i += run;
690 j = scantable[i];
691 if(level<0){
692 level= -level;
693 level= (level*qscale*quant_matrix[j])>>4;
694 level= (level-1)|1;
695 level= -level;
696 }else{
697 level= (level*qscale*quant_matrix[j])>>4;
698 level= (level-1)|1;
701 if (i > 63){
702 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
703 return -1;
706 block[j] = level;
708 CLOSE_READER(re, &s->gb);
710 s->block_last_index[n] = i;
711 return 0;
714 static inline int mpeg1_decode_block_inter(MpegEncContext *s,
715 DCTELEM *block,
716 int n)
718 int level, i, j, run;
719 RLTable *rl = &ff_rl_mpeg1;
720 uint8_t * const scantable= s->intra_scantable.permutated;
721 const uint16_t *quant_matrix= s->inter_matrix;
722 const int qscale= s->qscale;
725 OPEN_READER(re, &s->gb);
726 i = -1;
727 /* special case for the first coef. no need to add a second vlc table */
728 UPDATE_CACHE(re, &s->gb);
729 if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
730 level= (3*qscale*quant_matrix[0])>>5;
731 level= (level-1)|1;
732 if(GET_CACHE(re, &s->gb)&0x40000000)
733 level= -level;
734 block[0] = level;
735 i++;
736 SKIP_BITS(re, &s->gb, 2);
737 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
738 goto end;
740 #if MIN_CACHE_BITS < 19
741 UPDATE_CACHE(re, &s->gb);
742 #endif
743 /* now quantify & encode AC coefs */
744 for(;;) {
745 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
747 if(level != 0) {
748 i += run;
749 j = scantable[i];
750 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
751 level= (level-1)|1;
752 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
753 SKIP_BITS(re, &s->gb, 1);
754 } else {
755 /* escape */
756 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
757 UPDATE_CACHE(re, &s->gb);
758 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
759 if (level == -128) {
760 level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
761 } else if (level == 0) {
762 level = SHOW_UBITS(re, &s->gb, 8) ; SKIP_BITS(re, &s->gb, 8);
764 i += run;
765 j = scantable[i];
766 if(level<0){
767 level= -level;
768 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
769 level= (level-1)|1;
770 level= -level;
771 }else{
772 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
773 level= (level-1)|1;
776 if (i > 63){
777 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
778 return -1;
781 block[j] = level;
782 #if MIN_CACHE_BITS < 19
783 UPDATE_CACHE(re, &s->gb);
784 #endif
785 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
786 break;
787 #if MIN_CACHE_BITS >= 19
788 UPDATE_CACHE(re, &s->gb);
789 #endif
791 end:
792 LAST_SKIP_BITS(re, &s->gb, 2);
793 CLOSE_READER(re, &s->gb);
795 s->block_last_index[n] = i;
796 return 0;
799 static inline int mpeg1_fast_decode_block_inter(MpegEncContext *s, DCTELEM *block, int n)
801 int level, i, j, run;
802 RLTable *rl = &ff_rl_mpeg1;
803 uint8_t * const scantable= s->intra_scantable.permutated;
804 const int qscale= s->qscale;
807 OPEN_READER(re, &s->gb);
808 i = -1;
809 /* special case for the first coef. no need to add a second vlc table */
810 UPDATE_CACHE(re, &s->gb);
811 if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
812 level= (3*qscale)>>1;
813 level= (level-1)|1;
814 if(GET_CACHE(re, &s->gb)&0x40000000)
815 level= -level;
816 block[0] = level;
817 i++;
818 SKIP_BITS(re, &s->gb, 2);
819 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
820 goto end;
822 #if MIN_CACHE_BITS < 19
823 UPDATE_CACHE(re, &s->gb);
824 #endif
826 /* now quantify & encode AC coefs */
827 for(;;) {
828 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
830 if(level != 0) {
831 i += run;
832 j = scantable[i];
833 level= ((level*2+1)*qscale)>>1;
834 level= (level-1)|1;
835 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
836 SKIP_BITS(re, &s->gb, 1);
837 } else {
838 /* escape */
839 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
840 UPDATE_CACHE(re, &s->gb);
841 level = SHOW_SBITS(re, &s->gb, 8); SKIP_BITS(re, &s->gb, 8);
842 if (level == -128) {
843 level = SHOW_UBITS(re, &s->gb, 8) - 256; SKIP_BITS(re, &s->gb, 8);
844 } else if (level == 0) {
845 level = SHOW_UBITS(re, &s->gb, 8) ; SKIP_BITS(re, &s->gb, 8);
847 i += run;
848 j = scantable[i];
849 if(level<0){
850 level= -level;
851 level= ((level*2+1)*qscale)>>1;
852 level= (level-1)|1;
853 level= -level;
854 }else{
855 level= ((level*2+1)*qscale)>>1;
856 level= (level-1)|1;
860 block[j] = level;
861 #if MIN_CACHE_BITS < 19
862 UPDATE_CACHE(re, &s->gb);
863 #endif
864 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
865 break;
866 #if MIN_CACHE_BITS >= 19
867 UPDATE_CACHE(re, &s->gb);
868 #endif
870 end:
871 LAST_SKIP_BITS(re, &s->gb, 2);
872 CLOSE_READER(re, &s->gb);
874 s->block_last_index[n] = i;
875 return 0;
879 static inline int mpeg2_decode_block_non_intra(MpegEncContext *s,
880 DCTELEM *block,
881 int n)
883 int level, i, j, run;
884 RLTable *rl = &ff_rl_mpeg1;
885 uint8_t * const scantable= s->intra_scantable.permutated;
886 const uint16_t *quant_matrix;
887 const int qscale= s->qscale;
888 int mismatch;
890 mismatch = 1;
893 OPEN_READER(re, &s->gb);
894 i = -1;
895 if (n < 4)
896 quant_matrix = s->inter_matrix;
897 else
898 quant_matrix = s->chroma_inter_matrix;
900 /* special case for the first coef. no need to add a second vlc table */
901 UPDATE_CACHE(re, &s->gb);
902 if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
903 level= (3*qscale*quant_matrix[0])>>5;
904 if(GET_CACHE(re, &s->gb)&0x40000000)
905 level= -level;
906 block[0] = level;
907 mismatch ^= level;
908 i++;
909 SKIP_BITS(re, &s->gb, 2);
910 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
911 goto end;
913 #if MIN_CACHE_BITS < 19
914 UPDATE_CACHE(re, &s->gb);
915 #endif
917 /* now quantify & encode AC coefs */
918 for(;;) {
919 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
921 if(level != 0) {
922 i += run;
923 j = scantable[i];
924 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
925 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
926 SKIP_BITS(re, &s->gb, 1);
927 } else {
928 /* escape */
929 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
930 UPDATE_CACHE(re, &s->gb);
931 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
933 i += run;
934 j = scantable[i];
935 if(level<0){
936 level= ((-level*2+1)*qscale*quant_matrix[j])>>5;
937 level= -level;
938 }else{
939 level= ((level*2+1)*qscale*quant_matrix[j])>>5;
942 if (i > 63){
943 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
944 return -1;
947 mismatch ^= level;
948 block[j] = level;
949 #if MIN_CACHE_BITS < 19
950 UPDATE_CACHE(re, &s->gb);
951 #endif
952 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
953 break;
954 #if MIN_CACHE_BITS >= 19
955 UPDATE_CACHE(re, &s->gb);
956 #endif
958 end:
959 LAST_SKIP_BITS(re, &s->gb, 2);
960 CLOSE_READER(re, &s->gb);
962 block[63] ^= (mismatch & 1);
964 s->block_last_index[n] = i;
965 return 0;
968 static inline int mpeg2_fast_decode_block_non_intra(MpegEncContext *s,
969 DCTELEM *block,
970 int n)
972 int level, i, j, run;
973 RLTable *rl = &ff_rl_mpeg1;
974 uint8_t * const scantable= s->intra_scantable.permutated;
975 const int qscale= s->qscale;
976 OPEN_READER(re, &s->gb);
977 i = -1;
979 /* special case for the first coef. no need to add a second vlc table */
980 UPDATE_CACHE(re, &s->gb);
981 if (((int32_t)GET_CACHE(re, &s->gb)) < 0) {
982 level= (3*qscale)>>1;
983 if(GET_CACHE(re, &s->gb)&0x40000000)
984 level= -level;
985 block[0] = level;
986 i++;
987 SKIP_BITS(re, &s->gb, 2);
988 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
989 goto end;
991 #if MIN_CACHE_BITS < 19
992 UPDATE_CACHE(re, &s->gb);
993 #endif
995 /* now quantify & encode AC coefs */
996 for(;;) {
997 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
999 if(level != 0) {
1000 i += run;
1001 j = scantable[i];
1002 level= ((level*2+1)*qscale)>>1;
1003 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1004 SKIP_BITS(re, &s->gb, 1);
1005 } else {
1006 /* escape */
1007 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1008 UPDATE_CACHE(re, &s->gb);
1009 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1011 i += run;
1012 j = scantable[i];
1013 if(level<0){
1014 level= ((-level*2+1)*qscale)>>1;
1015 level= -level;
1016 }else{
1017 level= ((level*2+1)*qscale)>>1;
1021 block[j] = level;
1022 #if MIN_CACHE_BITS < 19
1023 UPDATE_CACHE(re, &s->gb);
1024 #endif
1025 if(((int32_t)GET_CACHE(re, &s->gb)) <= (int32_t)0xBFFFFFFF)
1026 break;
1027 #if MIN_CACHE_BITS >=19
1028 UPDATE_CACHE(re, &s->gb);
1029 #endif
1031 end:
1032 LAST_SKIP_BITS(re, &s->gb, 2);
1033 CLOSE_READER(re, &s->gb);
1034 s->block_last_index[n] = i;
1035 return 0;
1039 static inline int mpeg2_decode_block_intra(MpegEncContext *s,
1040 DCTELEM *block,
1041 int n)
1043 int level, dc, diff, i, j, run;
1044 int component;
1045 RLTable *rl;
1046 uint8_t * const scantable= s->intra_scantable.permutated;
1047 const uint16_t *quant_matrix;
1048 const int qscale= s->qscale;
1049 int mismatch;
1051 /* DC coef */
1052 if (n < 4){
1053 quant_matrix = s->intra_matrix;
1054 component = 0;
1055 }else{
1056 quant_matrix = s->chroma_intra_matrix;
1057 component = (n&1) + 1;
1059 diff = decode_dc(&s->gb, component);
1060 if (diff >= 0xffff)
1061 return -1;
1062 dc = s->last_dc[component];
1063 dc += diff;
1064 s->last_dc[component] = dc;
1065 block[0] = dc << (3 - s->intra_dc_precision);
1066 dprintf(s->avctx, "dc=%d\n", block[0]);
1067 mismatch = block[0] ^ 1;
1068 i = 0;
1069 if (s->intra_vlc_format)
1070 rl = &ff_rl_mpeg2;
1071 else
1072 rl = &ff_rl_mpeg1;
1075 OPEN_READER(re, &s->gb);
1076 /* now quantify & encode AC coefs */
1077 for(;;) {
1078 UPDATE_CACHE(re, &s->gb);
1079 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1081 if(level == 127){
1082 break;
1083 } else if(level != 0) {
1084 i += run;
1085 j = scantable[i];
1086 level= (level*qscale*quant_matrix[j])>>4;
1087 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1088 LAST_SKIP_BITS(re, &s->gb, 1);
1089 } else {
1090 /* escape */
1091 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1092 UPDATE_CACHE(re, &s->gb);
1093 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1094 i += run;
1095 j = scantable[i];
1096 if(level<0){
1097 level= (-level*qscale*quant_matrix[j])>>4;
1098 level= -level;
1099 }else{
1100 level= (level*qscale*quant_matrix[j])>>4;
1103 if (i > 63){
1104 av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
1105 return -1;
1108 mismatch^= level;
1109 block[j] = level;
1111 CLOSE_READER(re, &s->gb);
1113 block[63]^= mismatch&1;
1115 s->block_last_index[n] = i;
1116 return 0;
1119 static inline int mpeg2_fast_decode_block_intra(MpegEncContext *s,
1120 DCTELEM *block,
1121 int n)
1123 int level, dc, diff, j, run;
1124 int component;
1125 RLTable *rl;
1126 uint8_t * scantable= s->intra_scantable.permutated;
1127 const uint16_t *quant_matrix;
1128 const int qscale= s->qscale;
1130 /* DC coef */
1131 if (n < 4){
1132 quant_matrix = s->intra_matrix;
1133 component = 0;
1134 }else{
1135 quant_matrix = s->chroma_intra_matrix;
1136 component = (n&1) + 1;
1138 diff = decode_dc(&s->gb, component);
1139 if (diff >= 0xffff)
1140 return -1;
1141 dc = s->last_dc[component];
1142 dc += diff;
1143 s->last_dc[component] = dc;
1144 block[0] = dc << (3 - s->intra_dc_precision);
1145 if (s->intra_vlc_format)
1146 rl = &ff_rl_mpeg2;
1147 else
1148 rl = &ff_rl_mpeg1;
1151 OPEN_READER(re, &s->gb);
1152 /* now quantify & encode AC coefs */
1153 for(;;) {
1154 UPDATE_CACHE(re, &s->gb);
1155 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
1157 if(level == 127){
1158 break;
1159 } else if(level != 0) {
1160 scantable += run;
1161 j = *scantable;
1162 level= (level*qscale*quant_matrix[j])>>4;
1163 level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
1164 LAST_SKIP_BITS(re, &s->gb, 1);
1165 } else {
1166 /* escape */
1167 run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
1168 UPDATE_CACHE(re, &s->gb);
1169 level = SHOW_SBITS(re, &s->gb, 12); SKIP_BITS(re, &s->gb, 12);
1170 scantable += run;
1171 j = *scantable;
1172 if(level<0){
1173 level= (-level*qscale*quant_matrix[j])>>4;
1174 level= -level;
1175 }else{
1176 level= (level*qscale*quant_matrix[j])>>4;
1180 block[j] = level;
1182 CLOSE_READER(re, &s->gb);
1185 s->block_last_index[n] = scantable - s->intra_scantable.permutated;
1186 return 0;
1189 typedef struct Mpeg1Context {
1190 MpegEncContext mpeg_enc_ctx;
1191 int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1192 int repeat_field; /* true if we must repeat the field */
1193 AVPanScan pan_scan; /** some temporary storage for the panscan */
1194 int slice_count;
1195 int swap_uv;//indicate VCR2
1196 int save_aspect_info;
1197 int save_width, save_height;
1198 AVRational frame_rate_ext; ///< MPEG-2 specific framerate modificator
1200 } Mpeg1Context;
1202 static int mpeg_decode_init(AVCodecContext *avctx)
1204 Mpeg1Context *s = avctx->priv_data;
1205 MpegEncContext *s2 = &s->mpeg_enc_ctx;
1206 int i;
1208 //we need some parmutation to store
1209 //matrixes, until MPV_common_init()
1210 //set the real permutatuon
1211 for(i=0;i<64;i++)
1212 s2->dsp.idct_permutation[i]=i;
1214 MPV_decode_defaults(s2);
1216 s->mpeg_enc_ctx.avctx= avctx;
1217 s->mpeg_enc_ctx.flags= avctx->flags;
1218 s->mpeg_enc_ctx.flags2= avctx->flags2;
1219 ff_mpeg12_common_init(&s->mpeg_enc_ctx);
1220 init_vlcs();
1222 s->mpeg_enc_ctx_allocated = 0;
1223 s->mpeg_enc_ctx.picture_number = 0;
1224 s->repeat_field = 0;
1225 s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1226 return 0;
1229 static void quant_matrix_rebuild(uint16_t *matrix, const uint8_t *old_perm,
1230 const uint8_t *new_perm){
1231 uint16_t temp_matrix[64];
1232 int i;
1234 memcpy(temp_matrix,matrix,64*sizeof(uint16_t));
1236 for(i=0;i<64;i++){
1237 matrix[new_perm[i]] = temp_matrix[old_perm[i]];
1241 //Call this function when we know all parameters
1242 //it may be called in different places for mpeg1 and mpeg2
1243 static int mpeg_decode_postinit(AVCodecContext *avctx){
1244 Mpeg1Context *s1 = avctx->priv_data;
1245 MpegEncContext *s = &s1->mpeg_enc_ctx;
1246 uint8_t old_permutation[64];
1248 if (
1249 (s1->mpeg_enc_ctx_allocated == 0)||
1250 avctx->coded_width != s->width ||
1251 avctx->coded_height != s->height||
1252 s1->save_width != s->width ||
1253 s1->save_height != s->height ||
1254 s1->save_aspect_info != s->aspect_ratio_info||
1258 if (s1->mpeg_enc_ctx_allocated) {
1259 ParseContext pc= s->parse_context;
1260 s->parse_context.buffer=0;
1261 MPV_common_end(s);
1262 s->parse_context= pc;
1265 if( (s->width == 0 )||(s->height == 0))
1266 return -2;
1268 avcodec_set_dimensions(avctx, s->width, s->height);
1269 avctx->bit_rate = s->bit_rate;
1270 s1->save_aspect_info = s->aspect_ratio_info;
1271 s1->save_width = s->width;
1272 s1->save_height = s->height;
1274 //low_delay may be forced, in this case we will have B frames
1275 //that behave like P frames
1276 avctx->has_b_frames = !(s->low_delay);
1278 if(avctx->sub_id==1){//s->codec_id==avctx->codec_id==CODEC_ID
1279 //mpeg1 fps
1280 avctx->time_base.den= ff_frame_rate_tab[s->frame_rate_index].num;
1281 avctx->time_base.num= ff_frame_rate_tab[s->frame_rate_index].den;
1282 //mpeg1 aspect
1283 avctx->sample_aspect_ratio= av_d2q(
1284 1.0/ff_mpeg1_aspect[s->aspect_ratio_info], 255);
1286 }else{//mpeg2
1287 //mpeg2 fps
1288 av_reduce(
1289 &s->avctx->time_base.den,
1290 &s->avctx->time_base.num,
1291 ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
1292 ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
1293 1<<30);
1294 //mpeg2 aspect
1295 if(s->aspect_ratio_info > 1){
1296 if( (s1->pan_scan.width == 0 )||(s1->pan_scan.height == 0) ){
1297 s->avctx->sample_aspect_ratio=
1298 av_div_q(
1299 ff_mpeg2_aspect[s->aspect_ratio_info],
1300 (AVRational){s->width, s->height}
1302 }else{
1303 s->avctx->sample_aspect_ratio=
1304 av_div_q(
1305 ff_mpeg2_aspect[s->aspect_ratio_info],
1306 (AVRational){s1->pan_scan.width, s1->pan_scan.height}
1309 }else{
1310 s->avctx->sample_aspect_ratio=
1311 ff_mpeg2_aspect[s->aspect_ratio_info];
1313 }//mpeg2
1315 if(avctx->xvmc_acceleration){
1316 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
1317 }else{
1318 if(s->chroma_format < 2){
1319 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
1320 }else
1321 if(s->chroma_format == 2){
1322 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_422);
1323 }else
1324 if(s->chroma_format > 2){
1325 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_444);
1328 //until then pix_fmt may be changed right after codec init
1329 if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
1330 if( avctx->idct_algo == FF_IDCT_AUTO )
1331 avctx->idct_algo = FF_IDCT_SIMPLE;
1333 //quantization matrixes may need reordering
1334 //if dct permutation is changed
1335 memcpy(old_permutation,s->dsp.idct_permutation,64*sizeof(uint8_t));
1337 if (MPV_common_init(s) < 0)
1338 return -2;
1340 quant_matrix_rebuild(s->intra_matrix, old_permutation,s->dsp.idct_permutation);
1341 quant_matrix_rebuild(s->inter_matrix, old_permutation,s->dsp.idct_permutation);
1342 quant_matrix_rebuild(s->chroma_intra_matrix,old_permutation,s->dsp.idct_permutation);
1343 quant_matrix_rebuild(s->chroma_inter_matrix,old_permutation,s->dsp.idct_permutation);
1345 s1->mpeg_enc_ctx_allocated = 1;
1347 return 0;
1350 static int mpeg1_decode_picture(AVCodecContext *avctx,
1351 const uint8_t *buf, int buf_size)
1353 Mpeg1Context *s1 = avctx->priv_data;
1354 MpegEncContext *s = &s1->mpeg_enc_ctx;
1355 int ref, f_code, vbv_delay;
1357 if(mpeg_decode_postinit(s->avctx) < 0)
1358 return -2;
1360 init_get_bits(&s->gb, buf, buf_size*8);
1362 ref = get_bits(&s->gb, 10); /* temporal ref */
1363 s->pict_type = get_bits(&s->gb, 3);
1364 if(s->pict_type == 0 || s->pict_type > 3)
1365 return -1;
1367 vbv_delay= get_bits(&s->gb, 16);
1368 if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
1369 s->full_pel[0] = get_bits1(&s->gb);
1370 f_code = get_bits(&s->gb, 3);
1371 if (f_code == 0 && avctx->error_resilience >= FF_ER_COMPLIANT)
1372 return -1;
1373 s->mpeg_f_code[0][0] = f_code;
1374 s->mpeg_f_code[0][1] = f_code;
1376 if (s->pict_type == B_TYPE) {
1377 s->full_pel[1] = get_bits1(&s->gb);
1378 f_code = get_bits(&s->gb, 3);
1379 if (f_code == 0 && avctx->error_resilience >= FF_ER_COMPLIANT)
1380 return -1;
1381 s->mpeg_f_code[1][0] = f_code;
1382 s->mpeg_f_code[1][1] = f_code;
1384 s->current_picture.pict_type= s->pict_type;
1385 s->current_picture.key_frame= s->pict_type == I_TYPE;
1387 if(avctx->debug & FF_DEBUG_PICT_INFO)
1388 av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type);
1390 s->y_dc_scale = 8;
1391 s->c_dc_scale = 8;
1392 s->first_slice = 1;
1393 return 0;
1396 static void mpeg_decode_sequence_extension(Mpeg1Context *s1)
1398 MpegEncContext *s= &s1->mpeg_enc_ctx;
1399 int horiz_size_ext, vert_size_ext;
1400 int bit_rate_ext;
1402 skip_bits(&s->gb, 1); /* profil and level esc*/
1403 s->avctx->profile= get_bits(&s->gb, 3);
1404 s->avctx->level= get_bits(&s->gb, 4);
1405 s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1406 s->chroma_format = get_bits(&s->gb, 2); /* chroma_format 1=420, 2=422, 3=444 */
1407 horiz_size_ext = get_bits(&s->gb, 2);
1408 vert_size_ext = get_bits(&s->gb, 2);
1409 s->width |= (horiz_size_ext << 12);
1410 s->height |= (vert_size_ext << 12);
1411 bit_rate_ext = get_bits(&s->gb, 12); /* XXX: handle it */
1412 s->bit_rate += (bit_rate_ext << 18) * 400;
1413 skip_bits1(&s->gb); /* marker */
1414 s->avctx->rc_buffer_size += get_bits(&s->gb, 8)*1024*16<<10;
1416 s->low_delay = get_bits1(&s->gb);
1417 if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
1419 s1->frame_rate_ext.num = get_bits(&s->gb, 2)+1;
1420 s1->frame_rate_ext.den = get_bits(&s->gb, 5)+1;
1422 dprintf(s->avctx, "sequence extension\n");
1423 s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
1424 s->avctx->sub_id = 2; /* indicates mpeg2 found */
1426 if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1427 av_log(s->avctx, AV_LOG_DEBUG, "profile: %d, level: %d vbv buffer: %d, bitrate:%d\n",
1428 s->avctx->profile, s->avctx->level, s->avctx->rc_buffer_size, s->bit_rate);
1432 static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
1434 MpegEncContext *s= &s1->mpeg_enc_ctx;
1435 int color_description, w, h;
1437 skip_bits(&s->gb, 3); /* video format */
1438 color_description= get_bits1(&s->gb);
1439 if(color_description){
1440 skip_bits(&s->gb, 8); /* color primaries */
1441 skip_bits(&s->gb, 8); /* transfer_characteristics */
1442 skip_bits(&s->gb, 8); /* matrix_coefficients */
1444 w= get_bits(&s->gb, 14);
1445 skip_bits(&s->gb, 1); //marker
1446 h= get_bits(&s->gb, 14);
1447 skip_bits(&s->gb, 1); //marker
1449 s1->pan_scan.width= 16*w;
1450 s1->pan_scan.height=16*h;
1452 if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1453 av_log(s->avctx, AV_LOG_DEBUG, "sde w:%d, h:%d\n", w, h);
1456 static void mpeg_decode_picture_display_extension(Mpeg1Context *s1)
1458 MpegEncContext *s= &s1->mpeg_enc_ctx;
1459 int i,nofco;
1461 nofco = 1;
1462 if(s->progressive_sequence){
1463 if(s->repeat_first_field){
1464 nofco++;
1465 if(s->top_field_first)
1466 nofco++;
1468 }else{
1469 if(s->picture_structure == PICT_FRAME){
1470 nofco++;
1471 if(s->repeat_first_field)
1472 nofco++;
1475 for(i=0; i<nofco; i++){
1476 s1->pan_scan.position[i][0]= get_sbits(&s->gb, 16);
1477 skip_bits(&s->gb, 1); //marker
1478 s1->pan_scan.position[i][1]= get_sbits(&s->gb, 16);
1479 skip_bits(&s->gb, 1); //marker
1482 if(s->avctx->debug & FF_DEBUG_PICT_INFO)
1483 av_log(s->avctx, AV_LOG_DEBUG, "pde (%d,%d) (%d,%d) (%d,%d)\n",
1484 s1->pan_scan.position[0][0], s1->pan_scan.position[0][1],
1485 s1->pan_scan.position[1][0], s1->pan_scan.position[1][1],
1486 s1->pan_scan.position[2][0], s1->pan_scan.position[2][1]
1490 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1492 int i, v, j;
1494 dprintf(s->avctx, "matrix extension\n");
1496 if (get_bits1(&s->gb)) {
1497 for(i=0;i<64;i++) {
1498 v = get_bits(&s->gb, 8);
1499 j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1500 s->intra_matrix[j] = v;
1501 s->chroma_intra_matrix[j] = v;
1504 if (get_bits1(&s->gb)) {
1505 for(i=0;i<64;i++) {
1506 v = get_bits(&s->gb, 8);
1507 j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1508 s->inter_matrix[j] = v;
1509 s->chroma_inter_matrix[j] = v;
1512 if (get_bits1(&s->gb)) {
1513 for(i=0;i<64;i++) {
1514 v = get_bits(&s->gb, 8);
1515 j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1516 s->chroma_intra_matrix[j] = v;
1519 if (get_bits1(&s->gb)) {
1520 for(i=0;i<64;i++) {
1521 v = get_bits(&s->gb, 8);
1522 j= s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1523 s->chroma_inter_matrix[j] = v;
1528 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1530 s->full_pel[0] = s->full_pel[1] = 0;
1531 s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1532 s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1533 s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1534 s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1535 s->intra_dc_precision = get_bits(&s->gb, 2);
1536 s->picture_structure = get_bits(&s->gb, 2);
1537 s->top_field_first = get_bits1(&s->gb);
1538 s->frame_pred_frame_dct = get_bits1(&s->gb);
1539 s->concealment_motion_vectors = get_bits1(&s->gb);
1540 s->q_scale_type = get_bits1(&s->gb);
1541 s->intra_vlc_format = get_bits1(&s->gb);
1542 s->alternate_scan = get_bits1(&s->gb);
1543 s->repeat_first_field = get_bits1(&s->gb);
1544 s->chroma_420_type = get_bits1(&s->gb);
1545 s->progressive_frame = get_bits1(&s->gb);
1547 if(s->picture_structure == PICT_FRAME){
1548 s->first_field=0;
1549 s->v_edge_pos= 16*s->mb_height;
1550 }else{
1551 s->first_field ^= 1;
1552 s->v_edge_pos= 8*s->mb_height;
1553 memset(s->mbskip_table, 0, s->mb_stride*s->mb_height);
1556 if(s->alternate_scan){
1557 ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable , ff_alternate_vertical_scan);
1558 ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable , ff_alternate_vertical_scan);
1559 }else{
1560 ff_init_scantable(s->dsp.idct_permutation, &s->inter_scantable , ff_zigzag_direct);
1561 ff_init_scantable(s->dsp.idct_permutation, &s->intra_scantable , ff_zigzag_direct);
1564 /* composite display not parsed */
1565 dprintf(s->avctx, "intra_dc_precision=%d\n", s->intra_dc_precision);
1566 dprintf(s->avctx, "picture_structure=%d\n", s->picture_structure);
1567 dprintf(s->avctx, "top field first=%d\n", s->top_field_first);
1568 dprintf(s->avctx, "repeat first field=%d\n", s->repeat_first_field);
1569 dprintf(s->avctx, "conceal=%d\n", s->concealment_motion_vectors);
1570 dprintf(s->avctx, "intra_vlc_format=%d\n", s->intra_vlc_format);
1571 dprintf(s->avctx, "alternate_scan=%d\n", s->alternate_scan);
1572 dprintf(s->avctx, "frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1573 dprintf(s->avctx, "progressive_frame=%d\n", s->progressive_frame);
1576 static void mpeg_decode_extension(AVCodecContext *avctx,
1577 const uint8_t *buf, int buf_size)
1579 Mpeg1Context *s1 = avctx->priv_data;
1580 MpegEncContext *s = &s1->mpeg_enc_ctx;
1581 int ext_type;
1583 init_get_bits(&s->gb, buf, buf_size*8);
1585 ext_type = get_bits(&s->gb, 4);
1586 switch(ext_type) {
1587 case 0x1:
1588 mpeg_decode_sequence_extension(s1);
1589 break;
1590 case 0x2:
1591 mpeg_decode_sequence_display_extension(s1);
1592 break;
1593 case 0x3:
1594 mpeg_decode_quant_matrix_extension(s);
1595 break;
1596 case 0x7:
1597 mpeg_decode_picture_display_extension(s1);
1598 break;
1599 case 0x8:
1600 mpeg_decode_picture_coding_extension(s);
1601 break;
1605 static void exchange_uv(MpegEncContext *s){
1606 short * tmp = s->pblocks[4];
1607 s->pblocks[4] = s->pblocks[5];
1608 s->pblocks[5] = tmp;
1611 static int mpeg_field_start(MpegEncContext *s){
1612 AVCodecContext *avctx= s->avctx;
1613 Mpeg1Context *s1 = (Mpeg1Context*)s;
1615 /* start frame decoding */
1616 if(s->first_field || s->picture_structure==PICT_FRAME){
1617 if(MPV_frame_start(s, avctx) < 0)
1618 return -1;
1620 ff_er_frame_start(s);
1622 /* first check if we must repeat the frame */
1623 s->current_picture_ptr->repeat_pict = 0;
1624 if (s->repeat_first_field) {
1625 if (s->progressive_sequence) {
1626 if (s->top_field_first)
1627 s->current_picture_ptr->repeat_pict = 4;
1628 else
1629 s->current_picture_ptr->repeat_pict = 2;
1630 } else if (s->progressive_frame) {
1631 s->current_picture_ptr->repeat_pict = 1;
1635 *s->current_picture_ptr->pan_scan= s1->pan_scan;
1636 }else{ //second field
1637 int i;
1639 if(!s->current_picture_ptr){
1640 av_log(s->avctx, AV_LOG_ERROR, "first field missing\n");
1641 return -1;
1644 for(i=0; i<4; i++){
1645 s->current_picture.data[i] = s->current_picture_ptr->data[i];
1646 if(s->picture_structure == PICT_BOTTOM_FIELD){
1647 s->current_picture.data[i] += s->current_picture_ptr->linesize[i];
1651 #ifdef HAVE_XVMC
1652 // MPV_frame_start will call this function too,
1653 // but we need to call it on every field
1654 if(s->avctx->xvmc_acceleration)
1655 XVMC_field_start(s,avctx);
1656 #endif
1658 return 0;
1661 #define DECODE_SLICE_ERROR -1
1662 #define DECODE_SLICE_OK 0
1665 * decodes a slice. MpegEncContext.mb_y must be set to the MB row from the startcode
1666 * @return DECODE_SLICE_ERROR if the slice is damaged<br>
1667 * DECODE_SLICE_OK if this slice is ok<br>
1669 static int mpeg_decode_slice(Mpeg1Context *s1, int mb_y,
1670 const uint8_t **buf, int buf_size)
1672 MpegEncContext *s = &s1->mpeg_enc_ctx;
1673 AVCodecContext *avctx= s->avctx;
1674 const int field_pic= s->picture_structure != PICT_FRAME;
1675 const int lowres= s->avctx->lowres;
1677 s->resync_mb_x=
1678 s->resync_mb_y= -1;
1680 if (mb_y<<field_pic >= s->mb_height){
1681 av_log(s->avctx, AV_LOG_ERROR, "slice below image (%d >= %d)\n", mb_y, s->mb_height);
1682 return -1;
1685 init_get_bits(&s->gb, *buf, buf_size*8);
1687 ff_mpeg1_clean_buffers(s);
1688 s->interlaced_dct = 0;
1690 s->qscale = get_qscale(s);
1692 if(s->qscale == 0){
1693 av_log(s->avctx, AV_LOG_ERROR, "qscale == 0\n");
1694 return -1;
1697 /* extra slice info */
1698 while (get_bits1(&s->gb) != 0) {
1699 skip_bits(&s->gb, 8);
1702 s->mb_x=0;
1704 for(;;) {
1705 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1706 if (code < 0){
1707 av_log(s->avctx, AV_LOG_ERROR, "first mb_incr damaged\n");
1708 return -1;
1710 if (code >= 33) {
1711 if (code == 33) {
1712 s->mb_x += 33;
1714 /* otherwise, stuffing, nothing to do */
1715 } else {
1716 s->mb_x += code;
1717 break;
1720 if(s->mb_x >= (unsigned)s->mb_width){
1721 av_log(s->avctx, AV_LOG_ERROR, "initial skip overflow\n");
1722 return -1;
1725 s->resync_mb_x= s->mb_x;
1726 s->resync_mb_y= s->mb_y= mb_y;
1727 s->mb_skip_run= 0;
1728 ff_init_block_index(s);
1730 if (s->mb_y==0 && s->mb_x==0 && (s->first_field || s->picture_structure==PICT_FRAME)) {
1731 if(s->avctx->debug&FF_DEBUG_PICT_INFO){
1732 av_log(s->avctx, AV_LOG_DEBUG, "qp:%d fc:%2d%2d%2d%2d %s %s %s %s %s dc:%d pstruct:%d fdct:%d cmv:%d qtype:%d ivlc:%d rff:%d %s\n",
1733 s->qscale, s->mpeg_f_code[0][0],s->mpeg_f_code[0][1],s->mpeg_f_code[1][0],s->mpeg_f_code[1][1],
1734 s->pict_type == I_TYPE ? "I" : (s->pict_type == P_TYPE ? "P" : (s->pict_type == B_TYPE ? "B" : "S")),
1735 s->progressive_sequence ? "ps" :"", s->progressive_frame ? "pf" : "", s->alternate_scan ? "alt" :"", s->top_field_first ? "top" :"",
1736 s->intra_dc_precision, s->picture_structure, s->frame_pred_frame_dct, s->concealment_motion_vectors,
1737 s->q_scale_type, s->intra_vlc_format, s->repeat_first_field, s->chroma_420_type ? "420" :"");
1741 for(;;) {
1742 #ifdef HAVE_XVMC
1743 //one 1 we memcpy blocks in xvmcvideo
1744 if(s->avctx->xvmc_acceleration > 1)
1745 XVMC_init_block(s);//set s->block
1746 #endif
1748 if(mpeg_decode_mb(s, s->block) < 0)
1749 return -1;
1751 if(s->current_picture.motion_val[0] && !s->encoding){ //note motion_val is normally NULL unless we want to extract the MVs
1752 const int wrap = field_pic ? 2*s->b8_stride : s->b8_stride;
1753 int xy = s->mb_x*2 + s->mb_y*2*wrap;
1754 int motion_x, motion_y, dir, i;
1755 if(field_pic && !s->first_field)
1756 xy += wrap/2;
1758 for(i=0; i<2; i++){
1759 for(dir=0; dir<2; dir++){
1760 if (s->mb_intra || (dir==1 && s->pict_type != B_TYPE)) {
1761 motion_x = motion_y = 0;
1762 }else if (s->mv_type == MV_TYPE_16X16 || (s->mv_type == MV_TYPE_FIELD && field_pic)){
1763 motion_x = s->mv[dir][0][0];
1764 motion_y = s->mv[dir][0][1];
1765 } else /*if ((s->mv_type == MV_TYPE_FIELD) || (s->mv_type == MV_TYPE_16X8))*/ {
1766 motion_x = s->mv[dir][i][0];
1767 motion_y = s->mv[dir][i][1];
1770 s->current_picture.motion_val[dir][xy ][0] = motion_x;
1771 s->current_picture.motion_val[dir][xy ][1] = motion_y;
1772 s->current_picture.motion_val[dir][xy + 1][0] = motion_x;
1773 s->current_picture.motion_val[dir][xy + 1][1] = motion_y;
1774 s->current_picture.ref_index [dir][xy ]=
1775 s->current_picture.ref_index [dir][xy + 1]= s->field_select[dir][i];
1776 assert(s->field_select[dir][i]==0 || s->field_select[dir][i]==1);
1778 xy += wrap;
1782 s->dest[0] += 16 >> lowres;
1783 s->dest[1] +=(16 >> lowres) >> s->chroma_x_shift;
1784 s->dest[2] +=(16 >> lowres) >> s->chroma_x_shift;
1786 MPV_decode_mb(s, s->block);
1788 if (++s->mb_x >= s->mb_width) {
1789 const int mb_size= 16>>s->avctx->lowres;
1791 ff_draw_horiz_band(s, mb_size*s->mb_y, mb_size);
1793 s->mb_x = 0;
1794 s->mb_y++;
1796 if(s->mb_y<<field_pic >= s->mb_height){
1797 int left= s->gb.size_in_bits - get_bits_count(&s->gb);
1798 int is_d10= s->chroma_format==2 && s->pict_type==I_TYPE && avctx->profile==0 && avctx->level==5
1799 && s->intra_dc_precision == 2 && s->q_scale_type == 1 && s->alternate_scan == 0
1800 && s->progressive_frame == 0 /* vbv_delay == 0xBBB || 0xE10*/;
1802 if(left < 0 || (left && show_bits(&s->gb, FFMIN(left, 23)) && !is_d10)
1803 || (avctx->error_resilience >= FF_ER_AGGRESSIVE && left>8)){
1804 av_log(avctx, AV_LOG_ERROR, "end mismatch left=%d %0X\n", left, show_bits(&s->gb, FFMIN(left, 23)));
1805 return -1;
1806 }else
1807 goto eos;
1810 ff_init_block_index(s);
1813 /* skip mb handling */
1814 if (s->mb_skip_run == -1) {
1815 /* read again increment */
1816 s->mb_skip_run = 0;
1817 for(;;) {
1818 int code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
1819 if (code < 0){
1820 av_log(s->avctx, AV_LOG_ERROR, "mb incr damaged\n");
1821 return -1;
1823 if (code >= 33) {
1824 if (code == 33) {
1825 s->mb_skip_run += 33;
1826 }else if(code == 35){
1827 if(s->mb_skip_run != 0 || show_bits(&s->gb, 15) != 0){
1828 av_log(s->avctx, AV_LOG_ERROR, "slice mismatch\n");
1829 return -1;
1831 goto eos; /* end of slice */
1833 /* otherwise, stuffing, nothing to do */
1834 } else {
1835 s->mb_skip_run += code;
1836 break;
1839 if(s->mb_skip_run){
1840 int i;
1841 if(s->pict_type == I_TYPE){
1842 av_log(s->avctx, AV_LOG_ERROR, "skipped MB in I frame at %d %d\n", s->mb_x, s->mb_y);
1843 return -1;
1846 /* skip mb */
1847 s->mb_intra = 0;
1848 for(i=0;i<12;i++)
1849 s->block_last_index[i] = -1;
1850 if(s->picture_structure == PICT_FRAME)
1851 s->mv_type = MV_TYPE_16X16;
1852 else
1853 s->mv_type = MV_TYPE_FIELD;
1854 if (s->pict_type == P_TYPE) {
1855 /* if P type, zero motion vector is implied */
1856 s->mv_dir = MV_DIR_FORWARD;
1857 s->mv[0][0][0] = s->mv[0][0][1] = 0;
1858 s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
1859 s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
1860 s->field_select[0][0]= s->picture_structure - 1;
1861 } else {
1862 /* if B type, reuse previous vectors and directions */
1863 s->mv[0][0][0] = s->last_mv[0][0][0];
1864 s->mv[0][0][1] = s->last_mv[0][0][1];
1865 s->mv[1][0][0] = s->last_mv[1][0][0];
1866 s->mv[1][0][1] = s->last_mv[1][0][1];
1871 eos: // end of slice
1872 *buf += get_bits_count(&s->gb)/8 - 1;
1873 //printf("y %d %d %d %d\n", s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y);
1874 return 0;
1877 static int slice_decode_thread(AVCodecContext *c, void *arg){
1878 MpegEncContext *s= arg;
1879 const uint8_t *buf= s->gb.buffer;
1880 int mb_y= s->start_mb_y;
1882 s->error_count= 3*(s->end_mb_y - s->start_mb_y)*s->mb_width;
1884 for(;;){
1885 uint32_t start_code;
1886 int ret;
1888 ret= mpeg_decode_slice((Mpeg1Context*)s, mb_y, &buf, s->gb.buffer_end - buf);
1889 emms_c();
1890 //av_log(c, AV_LOG_DEBUG, "ret:%d resync:%d/%d mb:%d/%d ts:%d/%d ec:%d\n",
1891 //ret, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, s->start_mb_y, s->end_mb_y, s->error_count);
1892 if(ret < 0){
1893 if(s->resync_mb_x>=0 && s->resync_mb_y>=0)
1894 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x, s->mb_y, AC_ERROR|DC_ERROR|MV_ERROR);
1895 }else{
1896 ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_END|DC_END|MV_END);
1899 if(s->mb_y == s->end_mb_y)
1900 return 0;
1902 start_code= -1;
1903 buf = ff_find_start_code(buf, s->gb.buffer_end, &start_code);
1904 mb_y= start_code - SLICE_MIN_START_CODE;
1905 if(mb_y < 0 || mb_y >= s->end_mb_y)
1906 return -1;
1909 return 0; //not reached
1913 * handles slice ends.
1914 * @return 1 if it seems to be the last slice of
1916 static int slice_end(AVCodecContext *avctx, AVFrame *pict)
1918 Mpeg1Context *s1 = avctx->priv_data;
1919 MpegEncContext *s = &s1->mpeg_enc_ctx;
1921 if (!s1->mpeg_enc_ctx_allocated || !s->current_picture_ptr)
1922 return 0;
1924 #ifdef HAVE_XVMC
1925 if(s->avctx->xvmc_acceleration)
1926 XVMC_field_end(s);
1927 #endif
1928 /* end of slice reached */
1929 if (/*s->mb_y<<field_pic == s->mb_height &&*/ !s->first_field) {
1930 /* end of image */
1932 s->current_picture_ptr->qscale_type= FF_QSCALE_TYPE_MPEG2;
1934 ff_er_frame_end(s);
1936 MPV_frame_end(s);
1938 if (s->pict_type == B_TYPE || s->low_delay) {
1939 *pict= *(AVFrame*)s->current_picture_ptr;
1940 ff_print_debug_info(s, pict);
1941 } else {
1942 s->picture_number++;
1943 /* latency of 1 frame for I and P frames */
1944 /* XXX: use another variable than picture_number */
1945 if (s->last_picture_ptr != NULL) {
1946 *pict= *(AVFrame*)s->last_picture_ptr;
1947 ff_print_debug_info(s, pict);
1951 return 1;
1952 } else {
1953 return 0;
1957 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1958 const uint8_t *buf, int buf_size)
1960 Mpeg1Context *s1 = avctx->priv_data;
1961 MpegEncContext *s = &s1->mpeg_enc_ctx;
1962 int width,height;
1963 int i, v, j;
1965 init_get_bits(&s->gb, buf, buf_size*8);
1967 width = get_bits(&s->gb, 12);
1968 height = get_bits(&s->gb, 12);
1969 if (width <= 0 || height <= 0 ||
1970 (width % 2) != 0 || (height % 2) != 0)
1971 return -1;
1972 s->aspect_ratio_info= get_bits(&s->gb, 4);
1973 if (s->aspect_ratio_info == 0)
1974 return -1;
1975 s->frame_rate_index = get_bits(&s->gb, 4);
1976 if (s->frame_rate_index == 0 || s->frame_rate_index > 13)
1977 return -1;
1978 s->bit_rate = get_bits(&s->gb, 18) * 400;
1979 if (get_bits1(&s->gb) == 0) /* marker */
1980 return -1;
1981 s->width = width;
1982 s->height = height;
1984 s->avctx->rc_buffer_size= get_bits(&s->gb, 10) * 1024*16;
1985 skip_bits(&s->gb, 1);
1987 /* get matrix */
1988 if (get_bits1(&s->gb)) {
1989 for(i=0;i<64;i++) {
1990 v = get_bits(&s->gb, 8);
1991 if(v==0){
1992 av_log(s->avctx, AV_LOG_ERROR, "intra matrix damaged\n");
1993 return -1;
1995 j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
1996 s->intra_matrix[j] = v;
1997 s->chroma_intra_matrix[j] = v;
1999 #ifdef DEBUG
2000 dprintf(s->avctx, "intra matrix present\n");
2001 for(i=0;i<64;i++)
2002 dprintf(s->avctx, " %d", s->intra_matrix[s->dsp.idct_permutation[i]]);
2003 dprintf(s->avctx, "\n");
2004 #endif
2005 } else {
2006 for(i=0;i<64;i++) {
2007 j = s->dsp.idct_permutation[i];
2008 v = ff_mpeg1_default_intra_matrix[i];
2009 s->intra_matrix[j] = v;
2010 s->chroma_intra_matrix[j] = v;
2013 if (get_bits1(&s->gb)) {
2014 for(i=0;i<64;i++) {
2015 v = get_bits(&s->gb, 8);
2016 if(v==0){
2017 av_log(s->avctx, AV_LOG_ERROR, "inter matrix damaged\n");
2018 return -1;
2020 j = s->dsp.idct_permutation[ ff_zigzag_direct[i] ];
2021 s->inter_matrix[j] = v;
2022 s->chroma_inter_matrix[j] = v;
2024 #ifdef DEBUG
2025 dprintf(s->avctx, "non intra matrix present\n");
2026 for(i=0;i<64;i++)
2027 dprintf(s->avctx, " %d", s->inter_matrix[s->dsp.idct_permutation[i]]);
2028 dprintf(s->avctx, "\n");
2029 #endif
2030 } else {
2031 for(i=0;i<64;i++) {
2032 int j= s->dsp.idct_permutation[i];
2033 v = ff_mpeg1_default_non_intra_matrix[i];
2034 s->inter_matrix[j] = v;
2035 s->chroma_inter_matrix[j] = v;
2039 if(show_bits(&s->gb, 23) != 0){
2040 av_log(s->avctx, AV_LOG_ERROR, "sequence header damaged\n");
2041 return -1;
2044 /* we set mpeg2 parameters so that it emulates mpeg1 */
2045 s->progressive_sequence = 1;
2046 s->progressive_frame = 1;
2047 s->picture_structure = PICT_FRAME;
2048 s->frame_pred_frame_dct = 1;
2049 s->chroma_format = 1;
2050 s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG1VIDEO;
2051 avctx->sub_id = 1; /* indicates mpeg1 */
2052 s->out_format = FMT_MPEG1;
2053 s->swap_uv = 0;//AFAIK VCR2 don't have SEQ_HEADER
2054 if(s->flags & CODEC_FLAG_LOW_DELAY) s->low_delay=1;
2056 if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2057 av_log(s->avctx, AV_LOG_DEBUG, "vbv buffer: %d, bitrate:%d\n",
2058 s->avctx->rc_buffer_size, s->bit_rate);
2060 return 0;
2063 static int vcr2_init_sequence(AVCodecContext *avctx)
2065 Mpeg1Context *s1 = avctx->priv_data;
2066 MpegEncContext *s = &s1->mpeg_enc_ctx;
2067 int i, v;
2069 /* start new mpeg1 context decoding */
2070 s->out_format = FMT_MPEG1;
2071 if (s1->mpeg_enc_ctx_allocated) {
2072 MPV_common_end(s);
2074 s->width = avctx->coded_width;
2075 s->height = avctx->coded_height;
2076 avctx->has_b_frames= 0; //true?
2077 s->low_delay= 1;
2079 if(avctx->xvmc_acceleration){
2080 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_xvmc_mpg2_420);
2081 }else{
2082 avctx->pix_fmt = avctx->get_format(avctx,pixfmt_yuv_420);
2085 if( avctx->pix_fmt == PIX_FMT_XVMC_MPEG2_IDCT )
2086 if( avctx->idct_algo == FF_IDCT_AUTO )
2087 avctx->idct_algo = FF_IDCT_SIMPLE;
2089 if (MPV_common_init(s) < 0)
2090 return -1;
2091 exchange_uv(s);//common init reset pblocks, so we swap them here
2092 s->swap_uv = 1;// in case of xvmc we need to swap uv for each MB
2093 s1->mpeg_enc_ctx_allocated = 1;
2095 for(i=0;i<64;i++) {
2096 int j= s->dsp.idct_permutation[i];
2097 v = ff_mpeg1_default_intra_matrix[i];
2098 s->intra_matrix[j] = v;
2099 s->chroma_intra_matrix[j] = v;
2101 v = ff_mpeg1_default_non_intra_matrix[i];
2102 s->inter_matrix[j] = v;
2103 s->chroma_inter_matrix[j] = v;
2106 s->progressive_sequence = 1;
2107 s->progressive_frame = 1;
2108 s->picture_structure = PICT_FRAME;
2109 s->frame_pred_frame_dct = 1;
2110 s->chroma_format = 1;
2111 s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
2112 avctx->sub_id = 2; /* indicates mpeg2 */
2113 return 0;
2117 static void mpeg_decode_user_data(AVCodecContext *avctx,
2118 const uint8_t *buf, int buf_size)
2120 const uint8_t *p;
2121 int len, flags;
2122 p = buf;
2123 len = buf_size;
2125 /* we parse the DTG active format information */
2126 if (len >= 5 &&
2127 p[0] == 'D' && p[1] == 'T' && p[2] == 'G' && p[3] == '1') {
2128 flags = p[4];
2129 p += 5;
2130 len -= 5;
2131 if (flags & 0x80) {
2132 /* skip event id */
2133 if (len < 2)
2134 return;
2135 p += 2;
2136 len -= 2;
2138 if (flags & 0x40) {
2139 if (len < 1)
2140 return;
2141 avctx->dtg_active_format = p[0] & 0x0f;
2146 static void mpeg_decode_gop(AVCodecContext *avctx,
2147 const uint8_t *buf, int buf_size){
2148 Mpeg1Context *s1 = avctx->priv_data;
2149 MpegEncContext *s = &s1->mpeg_enc_ctx;
2151 int drop_frame_flag;
2152 int time_code_hours, time_code_minutes;
2153 int time_code_seconds, time_code_pictures;
2154 int broken_link;
2156 init_get_bits(&s->gb, buf, buf_size*8);
2158 drop_frame_flag = get_bits1(&s->gb);
2160 time_code_hours=get_bits(&s->gb,5);
2161 time_code_minutes = get_bits(&s->gb,6);
2162 skip_bits1(&s->gb);//marker bit
2163 time_code_seconds = get_bits(&s->gb,6);
2164 time_code_pictures = get_bits(&s->gb,6);
2166 /*broken_link indicate that after editing the
2167 reference frames of the first B-Frames after GOP I-Frame
2168 are missing (open gop)*/
2169 broken_link = get_bits1(&s->gb);
2171 if(s->avctx->debug & FF_DEBUG_PICT_INFO)
2172 av_log(s->avctx, AV_LOG_DEBUG, "GOP (%2d:%02d:%02d.[%02d]) broken_link=%d\n",
2173 time_code_hours, time_code_minutes, time_code_seconds,
2174 time_code_pictures, broken_link);
2177 * finds the end of the current frame in the bitstream.
2178 * @return the position of the first byte of the next frame, or -1
2180 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
2182 int i;
2183 uint32_t state= pc->state;
2185 i=0;
2186 if(!pc->frame_start_found){
2187 for(i=0; i<buf_size; i++){
2188 i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2189 if(state >= SLICE_MIN_START_CODE && state <= SLICE_MAX_START_CODE){
2190 i++;
2191 pc->frame_start_found=1;
2192 break;
2194 if(state == SEQ_END_CODE){
2195 pc->state=-1;
2196 return i+1;
2201 if(pc->frame_start_found){
2202 /* EOF considered as end of frame */
2203 if (buf_size == 0)
2204 return 0;
2205 for(; i<buf_size; i++){
2206 i= ff_find_start_code(buf+i, buf+buf_size, &state) - buf - 1;
2207 if((state&0xFFFFFF00) == 0x100){
2208 if(state < SLICE_MIN_START_CODE || state > SLICE_MAX_START_CODE){
2209 pc->frame_start_found=0;
2210 pc->state=-1;
2211 return i-3;
2216 pc->state= state;
2217 return END_NOT_FOUND;
2220 /* handle buffering and image synchronisation */
2221 static int mpeg_decode_frame(AVCodecContext *avctx,
2222 void *data, int *data_size,
2223 uint8_t *buf, int buf_size)
2225 Mpeg1Context *s = avctx->priv_data;
2226 const uint8_t *buf_end;
2227 const uint8_t *buf_ptr;
2228 uint32_t start_code;
2229 int ret, input_size;
2230 AVFrame *picture = data;
2231 MpegEncContext *s2 = &s->mpeg_enc_ctx;
2232 dprintf(avctx, "fill_buffer\n");
2234 if (buf_size == 0 || (buf_size == 4 && AV_RB32(buf) == SEQ_END_CODE)) {
2235 /* special case for last picture */
2236 if (s2->low_delay==0 && s2->next_picture_ptr) {
2237 *picture= *(AVFrame*)s2->next_picture_ptr;
2238 s2->next_picture_ptr= NULL;
2240 *data_size = sizeof(AVFrame);
2242 return buf_size;
2245 if(s2->flags&CODEC_FLAG_TRUNCATED){
2246 int next= ff_mpeg1_find_frame_end(&s2->parse_context, buf, buf_size);
2248 if( ff_combine_frame(&s2->parse_context, next, (const uint8_t **)&buf, &buf_size) < 0 )
2249 return buf_size;
2252 buf_ptr = buf;
2253 buf_end = buf + buf_size;
2255 #if 0
2256 if (s->repeat_field % 2 == 1) {
2257 s->repeat_field++;
2258 //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
2259 // s2->picture_number, s->repeat_field);
2260 if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
2261 *data_size = sizeof(AVPicture);
2262 goto the_end;
2265 #endif
2267 if(s->mpeg_enc_ctx_allocated==0 && avctx->codec_tag == ff_get_fourcc("VCR2"))
2268 vcr2_init_sequence(avctx);
2270 s->slice_count= 0;
2272 for(;;) {
2273 /* find start next code */
2274 start_code = -1;
2275 buf_ptr = ff_find_start_code(buf_ptr,buf_end, &start_code);
2276 if (start_code > 0x1ff){
2277 if(s2->pict_type != B_TYPE || avctx->skip_frame <= AVDISCARD_DEFAULT){
2278 if(avctx->thread_count > 1){
2279 int i;
2281 avctx->execute(avctx, slice_decode_thread, (void**)&(s2->thread_context[0]), NULL, s->slice_count);
2282 for(i=0; i<s->slice_count; i++)
2283 s2->error_count += s2->thread_context[i]->error_count;
2285 if (slice_end(avctx, picture)) {
2286 if(s2->last_picture_ptr || s2->low_delay) //FIXME merge with the stuff in mpeg_decode_slice
2287 *data_size = sizeof(AVPicture);
2290 return FFMAX(0, buf_ptr - buf - s2->parse_context.last_index);
2293 input_size = buf_end - buf_ptr;
2295 if(avctx->debug & FF_DEBUG_STARTCODE){
2296 av_log(avctx, AV_LOG_DEBUG, "%3X at %zd left %d\n", start_code, buf_ptr-buf, input_size);
2299 /* prepare data for next start code */
2300 switch(start_code) {
2301 case SEQ_START_CODE:
2302 mpeg1_decode_sequence(avctx, buf_ptr,
2303 input_size);
2304 break;
2306 case PICTURE_START_CODE:
2307 /* we have a complete image : we try to decompress it */
2308 mpeg1_decode_picture(avctx,
2309 buf_ptr, input_size);
2310 break;
2311 case EXT_START_CODE:
2312 mpeg_decode_extension(avctx,
2313 buf_ptr, input_size);
2314 break;
2315 case USER_START_CODE:
2316 mpeg_decode_user_data(avctx,
2317 buf_ptr, input_size);
2318 break;
2319 case GOP_START_CODE:
2320 s2->first_field=0;
2321 mpeg_decode_gop(avctx,
2322 buf_ptr, input_size);
2323 break;
2324 default:
2325 if (start_code >= SLICE_MIN_START_CODE &&
2326 start_code <= SLICE_MAX_START_CODE) {
2327 int mb_y= start_code - SLICE_MIN_START_CODE;
2329 if(s2->last_picture_ptr==NULL){
2330 /* Skip B-frames if we do not have reference frames. */
2331 if(s2->pict_type==B_TYPE) break;
2333 if(s2->next_picture_ptr==NULL){
2334 /* Skip P-frames if we do not have reference frame no valid header. */
2335 if(s2->pict_type==P_TYPE && (s2->first_field || s2->picture_structure==PICT_FRAME)) break;
2337 /* Skip B-frames if we are in a hurry. */
2338 if(avctx->hurry_up && s2->pict_type==B_TYPE) break;
2339 if( (avctx->skip_frame >= AVDISCARD_NONREF && s2->pict_type==B_TYPE)
2340 ||(avctx->skip_frame >= AVDISCARD_NONKEY && s2->pict_type!=I_TYPE)
2341 || avctx->skip_frame >= AVDISCARD_ALL)
2342 break;
2343 /* Skip everything if we are in a hurry>=5. */
2344 if(avctx->hurry_up>=5) break;
2346 if (!s->mpeg_enc_ctx_allocated) break;
2348 if(s2->codec_id == CODEC_ID_MPEG2VIDEO){
2349 if(mb_y < avctx->skip_top || mb_y >= s2->mb_height - avctx->skip_bottom)
2350 break;
2353 if(s2->first_slice){
2354 s2->first_slice=0;
2355 if(mpeg_field_start(s2) < 0)
2356 return -1;
2358 if(!s2->current_picture_ptr){
2359 av_log(avctx, AV_LOG_ERROR, "current_picture not initialized\n");
2360 return -1;
2363 if(avctx->thread_count > 1){
2364 int threshold= (s2->mb_height*s->slice_count + avctx->thread_count/2) / avctx->thread_count;
2365 if(threshold <= mb_y){
2366 MpegEncContext *thread_context= s2->thread_context[s->slice_count];
2368 thread_context->start_mb_y= mb_y;
2369 thread_context->end_mb_y = s2->mb_height;
2370 if(s->slice_count){
2371 s2->thread_context[s->slice_count-1]->end_mb_y= mb_y;
2372 ff_update_duplicate_context(thread_context, s2);
2374 init_get_bits(&thread_context->gb, buf_ptr, input_size*8);
2375 s->slice_count++;
2377 buf_ptr += 2; //FIXME add minimum num of bytes per slice
2378 }else{
2379 ret = mpeg_decode_slice(s, mb_y, &buf_ptr, input_size);
2380 emms_c();
2382 if(ret < 0){
2383 if(s2->resync_mb_x>=0 && s2->resync_mb_y>=0)
2384 ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x, s2->mb_y, AC_ERROR|DC_ERROR|MV_ERROR);
2385 }else{
2386 ff_er_add_slice(s2, s2->resync_mb_x, s2->resync_mb_y, s2->mb_x-1, s2->mb_y, AC_END|DC_END|MV_END);
2390 break;
2395 static int mpeg_decode_end(AVCodecContext *avctx)
2397 Mpeg1Context *s = avctx->priv_data;
2399 if (s->mpeg_enc_ctx_allocated)
2400 MPV_common_end(&s->mpeg_enc_ctx);
2401 return 0;
2404 AVCodec mpeg1video_decoder = {
2405 "mpeg1video",
2406 CODEC_TYPE_VIDEO,
2407 CODEC_ID_MPEG1VIDEO,
2408 sizeof(Mpeg1Context),
2409 mpeg_decode_init,
2410 NULL,
2411 mpeg_decode_end,
2412 mpeg_decode_frame,
2413 CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2414 .flush= ff_mpeg_flush,
2417 AVCodec mpeg2video_decoder = {
2418 "mpeg2video",
2419 CODEC_TYPE_VIDEO,
2420 CODEC_ID_MPEG2VIDEO,
2421 sizeof(Mpeg1Context),
2422 mpeg_decode_init,
2423 NULL,
2424 mpeg_decode_end,
2425 mpeg_decode_frame,
2426 CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2427 .flush= ff_mpeg_flush,
2430 //legacy decoder
2431 AVCodec mpegvideo_decoder = {
2432 "mpegvideo",
2433 CODEC_TYPE_VIDEO,
2434 CODEC_ID_MPEG2VIDEO,
2435 sizeof(Mpeg1Context),
2436 mpeg_decode_init,
2437 NULL,
2438 mpeg_decode_end,
2439 mpeg_decode_frame,
2440 CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED | CODEC_CAP_DELAY,
2441 .flush= ff_mpeg_flush,
2444 #ifdef HAVE_XVMC
2445 static int mpeg_mc_decode_init(AVCodecContext *avctx){
2446 Mpeg1Context *s;
2448 if( avctx->thread_count > 1)
2449 return -1;
2450 if( !(avctx->slice_flags & SLICE_FLAG_CODED_ORDER) )
2451 return -1;
2452 if( !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD) ){
2453 dprintf(avctx, "mpeg12.c: XvMC decoder will work better if SLICE_FLAG_ALLOW_FIELD is set\n");
2455 mpeg_decode_init(avctx);
2456 s = avctx->priv_data;
2458 avctx->pix_fmt = PIX_FMT_XVMC_MPEG2_IDCT;
2459 avctx->xvmc_acceleration = 2;//2 - the blocks are packed!
2461 return 0;
2464 AVCodec mpeg_xvmc_decoder = {
2465 "mpegvideo_xvmc",
2466 CODEC_TYPE_VIDEO,
2467 CODEC_ID_MPEG2VIDEO_XVMC,
2468 sizeof(Mpeg1Context),
2469 mpeg_mc_decode_init,
2470 NULL,
2471 mpeg_decode_end,
2472 mpeg_decode_frame,
2473 CODEC_CAP_DRAW_HORIZ_BAND | CODEC_CAP_DR1 | CODEC_CAP_TRUNCATED| CODEC_CAP_HWACCEL | CODEC_CAP_DELAY,
2474 .flush= ff_mpeg_flush,
2477 #endif
2479 /* this is ugly i know, but the alternative is too make
2480 hundreds of vars global and prefix them with ff_mpeg1_
2481 which is far uglier. */
2482 #include "mdec.c"