repositories / deb_ffmpeg.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Imported Debian version 2.4.3~trusty1
[deb_ffmpeg.git] / ffmpeg / libavcodec / ituh263dec.c
CommitLineData
2ba45a60
DM		 1/*
2 * ITU H263 bitstream decoder
3 * Copyright (c) 2000,2001 Fabrice Bellard
4 * H263+ support.
5 * Copyright (c) 2001 Juan J. Sierralta P
6 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
7 *
8 * This file is part of FFmpeg.
9 *
10 * FFmpeg is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
14 *
15 * FFmpeg is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with FFmpeg; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
25/**
26 * @file
27 * h263 decoder.
28 */
29
30#define UNCHECKED_BITSTREAM_READER 1
31#include <limits.h>
32
33#include "libavutil/attributes.h"
34#include "libavutil/internal.h"
35#include "libavutil/mathematics.h"
36#include "avcodec.h"
37#include "mpegvideo.h"
38#include "h263.h"
39#include "mathops.h"
40#include "mpegutils.h"
41#include "unary.h"
42#include "flv.h"
43#include "mpeg4video.h"
44
45// The defines below define the number of bits that are read at once for
46// reading vlc values. Changing these may improve speed and data cache needs
47// be aware though that decreasing them may need the number of stages that is
48// passed to get_vlc* to be increased.
49#define MV_VLC_BITS 9
50#define H263_MBTYPE_B_VLC_BITS 6
51#define CBPC_B_VLC_BITS 3
52
53static const int h263_mb_type_b_map[15]= {
54 MB_TYPE_DIRECT2 | MB_TYPE_L0L1,
55 MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP,
56 MB_TYPE_DIRECT2 | MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT,
57 MB_TYPE_L0 | MB_TYPE_16x16,
58 MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_16x16,
59 MB_TYPE_L0 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16,
60 MB_TYPE_L1 | MB_TYPE_16x16,
61 MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_16x16,
62 MB_TYPE_L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16,
63 MB_TYPE_L0L1 | MB_TYPE_16x16,
64 MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_16x16,
65 MB_TYPE_L0L1 | MB_TYPE_CBP | MB_TYPE_QUANT | MB_TYPE_16x16,
66 0, //stuffing
67 MB_TYPE_INTRA4x4 | MB_TYPE_CBP,
68 MB_TYPE_INTRA4x4 | MB_TYPE_CBP | MB_TYPE_QUANT,
69};
70
71void ff_h263_show_pict_info(MpegEncContext *s){
72 if(s->avctx->debug&FF_DEBUG_PICT_INFO){
73 av_log(s->avctx, AV_LOG_DEBUG, "qp:%d %c size:%d rnd:%d%s%s%s%s%s%s%s%s%s %d/%d\n",
74 s->qscale, av_get_picture_type_char(s->pict_type),
75 s->gb.size_in_bits, 1-s->no_rounding,
76 s->obmc ? " AP" : "",
77 s->umvplus ? " UMV" : "",
78 s->h263_long_vectors ? " LONG" : "",
79 s->h263_plus ? " +" : "",
80 s->h263_aic ? " AIC" : "",
81 s->alt_inter_vlc ? " AIV" : "",
82 s->modified_quant ? " MQ" : "",
83 s->loop_filter ? " LOOP" : "",
84 s->h263_slice_structured ? " SS" : "",
85 s->avctx->time_base.den, s->avctx->time_base.num
86 );
87 }
88}
89
90/***********************************************/
91/* decoding */
92
93VLC ff_h263_intra_MCBPC_vlc;
94VLC ff_h263_inter_MCBPC_vlc;
95VLC ff_h263_cbpy_vlc;
96static VLC mv_vlc;
97static VLC h263_mbtype_b_vlc;
98static VLC cbpc_b_vlc;
99
100/* init vlcs */
101
102/* XXX: find a better solution to handle static init */
103av_cold void ff_h263_decode_init_vlc(void)
104{
105 static volatile int done = 0;
106
107 if (!done) {
108 INIT_VLC_STATIC(&ff_h263_intra_MCBPC_vlc, INTRA_MCBPC_VLC_BITS, 9,
109 ff_h263_intra_MCBPC_bits, 1, 1,
110 ff_h263_intra_MCBPC_code, 1, 1, 72);
111 INIT_VLC_STATIC(&ff_h263_inter_MCBPC_vlc, INTER_MCBPC_VLC_BITS, 28,
112 ff_h263_inter_MCBPC_bits, 1, 1,
113 ff_h263_inter_MCBPC_code, 1, 1, 198);
114 INIT_VLC_STATIC(&ff_h263_cbpy_vlc, CBPY_VLC_BITS, 16,
115 &ff_h263_cbpy_tab[0][1], 2, 1,
116 &ff_h263_cbpy_tab[0][0], 2, 1, 64);
117 INIT_VLC_STATIC(&mv_vlc, MV_VLC_BITS, 33,
118 &ff_mvtab[0][1], 2, 1,
119 &ff_mvtab[0][0], 2, 1, 538);
120 ff_init_rl(&ff_h263_rl_inter, ff_h263_static_rl_table_store[0]);
121 ff_init_rl(&ff_rl_intra_aic, ff_h263_static_rl_table_store[1]);
122 INIT_VLC_RL(ff_h263_rl_inter, 554);
123 INIT_VLC_RL(ff_rl_intra_aic, 554);
124 INIT_VLC_STATIC(&h263_mbtype_b_vlc, H263_MBTYPE_B_VLC_BITS, 15,
125 &ff_h263_mbtype_b_tab[0][1], 2, 1,
126 &ff_h263_mbtype_b_tab[0][0], 2, 1, 80);
127 INIT_VLC_STATIC(&cbpc_b_vlc, CBPC_B_VLC_BITS, 4,
128 &ff_cbpc_b_tab[0][1], 2, 1,
129 &ff_cbpc_b_tab[0][0], 2, 1, 8);
130 done = 1;
131 }
132}
133
134int ff_h263_decode_mba(MpegEncContext *s)
135{
136 int i, mb_pos;
137
138 for(i=0; i<6; i++){
139 if(s->mb_num-1 <= ff_mba_max[i]) break;
140 }
141 mb_pos= get_bits(&s->gb, ff_mba_length[i]);
142 s->mb_x= mb_pos % s->mb_width;
143 s->mb_y= mb_pos / s->mb_width;
144
145 return mb_pos;
146}
147
148/**
149 * Decode the group of blocks header or slice header.
150 * @return <0 if an error occurred
151 */
152static int h263_decode_gob_header(MpegEncContext *s)
153{
154 unsigned int val, gob_number;
155 int left;
156
157 /* Check for GOB Start Code */
158 val = show_bits(&s->gb, 16);
159 if(val)
160 return -1;
161
162 /* We have a GBSC probably with GSTUFF */
163 skip_bits(&s->gb, 16); /* Drop the zeros */
164 left= get_bits_left(&s->gb);
165 //MN: we must check the bits left or we might end in a infinite loop (or segfault)
166 for(;left>13; left--){
167 if(get_bits1(&s->gb)) break; /* Seek the '1' bit */
168 }
169 if(left<=13)
170 return -1;
171
172 if(s->h263_slice_structured){
173 if(get_bits1(&s->gb)==0)
174 return -1;
175
176 ff_h263_decode_mba(s);
177
178 if(s->mb_num > 1583)
179 if(get_bits1(&s->gb)==0)
180 return -1;
181
182 s->qscale = get_bits(&s->gb, 5); /* SQUANT */
183 if(get_bits1(&s->gb)==0)
184 return -1;
185 skip_bits(&s->gb, 2); /* GFID */
186 }else{
187 gob_number = get_bits(&s->gb, 5); /* GN */
188 s->mb_x= 0;
189 s->mb_y= s->gob_index* gob_number;
190 skip_bits(&s->gb, 2); /* GFID */
191 s->qscale = get_bits(&s->gb, 5); /* GQUANT */
192 }
193
194 if(s->mb_y >= s->mb_height)
195 return -1;
196
197 if(s->qscale==0)
198 return -1;
199
200 return 0;
201}
202
203/**
204 * Decode the group of blocks / video packet header.
205 * @return bit position of the resync_marker, or <0 if none was found
206 */
207int ff_h263_resync(MpegEncContext *s){
208 int left, pos, ret;
209
210 if(s->codec_id==AV_CODEC_ID_MPEG4){
211 skip_bits1(&s->gb);
212 align_get_bits(&s->gb);
213 }
214
215 if(show_bits(&s->gb, 16)==0){
216 pos= get_bits_count(&s->gb);
217 if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4)
218 ret= ff_mpeg4_decode_video_packet_header(s->avctx->priv_data);
219 else
220 ret= h263_decode_gob_header(s);
221 if(ret>=0)
222 return pos;
223 }
224 //OK, it's not where it is supposed to be ...
225 s->gb= s->last_resync_gb;
226 align_get_bits(&s->gb);
227 left= get_bits_left(&s->gb);
228
229 for(;left>16+1+5+5; left-=8){
230 if(show_bits(&s->gb, 16)==0){
231 GetBitContext bak= s->gb;
232
233 pos= get_bits_count(&s->gb);
234 if(CONFIG_MPEG4_DECODER && s->codec_id==AV_CODEC_ID_MPEG4)
235 ret= ff_mpeg4_decode_video_packet_header(s->avctx->priv_data);
236 else
237 ret= h263_decode_gob_header(s);
238 if(ret>=0)
239 return pos;
240
241 s->gb= bak;
242 }
243 skip_bits(&s->gb, 8);
244 }
245
246 return -1;
247}
248
249int ff_h263_decode_motion(MpegEncContext * s, int pred, int f_code)
250{
251 int code, val, sign, shift;
252 code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
253
254 if (code == 0)
255 return pred;
256 if (code < 0)
257 return 0xffff;
258
259 sign = get_bits1(&s->gb);
260 shift = f_code - 1;
261 val = code;
262 if (shift) {
263 val = (val - 1) << shift;
264 val |= get_bits(&s->gb, shift);
265 val++;
266 }
267 if (sign)
268 val = -val;
269 val += pred;
270
271 /* modulo decoding */
272 if (!s->h263_long_vectors) {
273 val = sign_extend(val, 5 + f_code);
274 } else {
275 /* horrible h263 long vector mode */
276 if (pred < -31 && val < -63)
277 val += 64;
278 if (pred > 32 && val > 63)
279 val -= 64;
280
281 }
282 return val;
283}
284
285
286/* Decode RVLC of H.263+ UMV */
287static int h263p_decode_umotion(MpegEncContext * s, int pred)
288{
289 int code = 0, sign;
290
291 if (get_bits1(&s->gb)) /* Motion difference = 0 */
292 return pred;
293
294 code = 2 + get_bits1(&s->gb);
295
296 while (get_bits1(&s->gb))
297 {
298 code <<= 1;
299 code += get_bits1(&s->gb);
300 }
301 sign = code & 1;
302 code >>= 1;
303
304 code = (sign) ? (pred - code) : (pred + code);
305 av_dlog(s->avctx,"H.263+ UMV Motion = %d\n", code);
306 return code;
307
308}
309
310/**
311 * read the next MVs for OBMC. yes this is a ugly hack, feel free to send a patch :)
312 */
313static void preview_obmc(MpegEncContext *s){
314 GetBitContext gb= s->gb;
315
316 int cbpc, i, pred_x, pred_y, mx, my;
317 int16_t *mot_val;
318 const int xy= s->mb_x + 1 + s->mb_y * s->mb_stride;
319 const int stride= s->b8_stride*2;
320
321 for(i=0; i<4; i++)
322 s->block_index[i]+= 2;
323 for(i=4; i<6; i++)
324 s->block_index[i]+= 1;
325 s->mb_x++;
326
327 av_assert2(s->pict_type == AV_PICTURE_TYPE_P);
328
329 do{
330 if (get_bits1(&s->gb)) {
331 /* skip mb */
332 mot_val = s->current_picture.motion_val[0][s->block_index[0]];
333 mot_val[0 ]= mot_val[2 ]=
334 mot_val[0+stride]= mot_val[2+stride]= 0;
335 mot_val[1 ]= mot_val[3 ]=
336 mot_val[1+stride]= mot_val[3+stride]= 0;
337
338 s->current_picture.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
339 goto end;
340 }
341 cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
342 }while(cbpc == 20);
343
344 if(cbpc & 4){
345 s->current_picture.mb_type[xy] = MB_TYPE_INTRA;
346 }else{
347 get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
348 if (cbpc & 8) {
349 if(s->modified_quant){
350 if(get_bits1(&s->gb)) skip_bits(&s->gb, 1);
351 else skip_bits(&s->gb, 5);
352 }else
353 skip_bits(&s->gb, 2);
354 }
355
356 if ((cbpc & 16) == 0) {
357 s->current_picture.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
358 /* 16x16 motion prediction */
359 mot_val= ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
360 if (s->umvplus)
361 mx = h263p_decode_umotion(s, pred_x);
362 else
363 mx = ff_h263_decode_motion(s, pred_x, 1);
364
365 if (s->umvplus)
366 my = h263p_decode_umotion(s, pred_y);
367 else
368 my = ff_h263_decode_motion(s, pred_y, 1);
369
370 mot_val[0 ]= mot_val[2 ]=
371 mot_val[0+stride]= mot_val[2+stride]= mx;
372 mot_val[1 ]= mot_val[3 ]=
373 mot_val[1+stride]= mot_val[3+stride]= my;
374 } else {
375 s->current_picture.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
376 for(i=0;i<4;i++) {
377 mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
378 if (s->umvplus)
379 mx = h263p_decode_umotion(s, pred_x);
380 else
381 mx = ff_h263_decode_motion(s, pred_x, 1);
382
383 if (s->umvplus)
384 my = h263p_decode_umotion(s, pred_y);
385 else
386 my = ff_h263_decode_motion(s, pred_y, 1);
387 if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
388 skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
389 mot_val[0] = mx;
390 mot_val[1] = my;
391 }
392 }
393 }
394end:
395
396 for(i=0; i<4; i++)
397 s->block_index[i]-= 2;
398 for(i=4; i<6; i++)
399 s->block_index[i]-= 1;
400 s->mb_x--;
401
402 s->gb= gb;
403}
404
405static void h263_decode_dquant(MpegEncContext *s){
406 static const int8_t quant_tab[4] = { -1, -2, 1, 2 };
407
408 if(s->modified_quant){
409 if(get_bits1(&s->gb))
410 s->qscale= ff_modified_quant_tab[get_bits1(&s->gb)][ s->qscale ];
411 else
412 s->qscale= get_bits(&s->gb, 5);
413 }else
414 s->qscale += quant_tab[get_bits(&s->gb, 2)];
415 ff_set_qscale(s, s->qscale);
416}
417
418static int h263_decode_block(MpegEncContext * s, int16_t * block,
419 int n, int coded)
420{
421 int level, i, j, run;
422 RLTable *rl = &ff_h263_rl_inter;
423 const uint8_t *scan_table;
424 GetBitContext gb= s->gb;
425
426 scan_table = s->intra_scantable.permutated;
427 if (s->h263_aic && s->mb_intra) {
428 rl = &ff_rl_intra_aic;
429 i = 0;
430 if (s->ac_pred) {
431 if (s->h263_aic_dir)
432 scan_table = s->intra_v_scantable.permutated; /* left */
433 else
434 scan_table = s->intra_h_scantable.permutated; /* top */
435 }
436 } else if (s->mb_intra) {
437 /* DC coef */
438 if(s->codec_id == AV_CODEC_ID_RV10){
439#if CONFIG_RV10_DECODER
440 if (s->rv10_version == 3 && s->pict_type == AV_PICTURE_TYPE_I) {
441 int component, diff;
442 component = (n <= 3 ? 0 : n - 4 + 1);
443 level = s->last_dc[component];
444 if (s->rv10_first_dc_coded[component]) {
445 diff = ff_rv_decode_dc(s, n);
446 if (diff == 0xffff)
447 return -1;
448 level += diff;
449 level = level & 0xff; /* handle wrap round */
450 s->last_dc[component] = level;
451 } else {
452 s->rv10_first_dc_coded[component] = 1;
453 }
454 } else {
455 level = get_bits(&s->gb, 8);
456 if (level == 255)
457 level = 128;
458 }
459#endif
460 }else{
461 level = get_bits(&s->gb, 8);
462 if((level&0x7F) == 0){
463 av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", level, s->mb_x, s->mb_y);
464 if(s->err_recognition & (AV_EF_BITSTREAM|AV_EF_COMPLIANT))
465 return -1;
466 }
467 if (level == 255)
468 level = 128;
469 }
470 block[0] = level;
471 i = 1;
472 } else {
473 i = 0;
474 }
475 if (!coded) {
476 if (s->mb_intra && s->h263_aic)
477 goto not_coded;
478 s->block_last_index[n] = i - 1;
479 return 0;
480 }
481retry:
482 {
483 OPEN_READER(re, &s->gb);
484 i--; // offset by -1 to allow direct indexing of scan_table
485 for(;;) {
486 UPDATE_CACHE(re, &s->gb);
487 GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
488 if (run == 66) {
489 if (level){
490 CLOSE_READER(re, &s->gb);
491 av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y);
492 return -1;
493 }
494 /* escape */
495 if (CONFIG_FLV_DECODER && s->h263_flv > 1) {
496 int is11 = SHOW_UBITS(re, &s->gb, 1);
497 SKIP_CACHE(re, &s->gb, 1);
498 run = SHOW_UBITS(re, &s->gb, 7) + 1;
499 if (is11) {
500 SKIP_COUNTER(re, &s->gb, 1 + 7);
501 UPDATE_CACHE(re, &s->gb);
502 level = SHOW_SBITS(re, &s->gb, 11);
503 SKIP_COUNTER(re, &s->gb, 11);
504 } else {
505 SKIP_CACHE(re, &s->gb, 7);
506 level = SHOW_SBITS(re, &s->gb, 7);
507 SKIP_COUNTER(re, &s->gb, 1 + 7 + 7);
508 }
509 } else {
510 run = SHOW_UBITS(re, &s->gb, 7) + 1;
511 SKIP_CACHE(re, &s->gb, 7);
512 level = (int8_t)SHOW_UBITS(re, &s->gb, 8);
513 SKIP_COUNTER(re, &s->gb, 7 + 8);
514 if(level == -128){
515 UPDATE_CACHE(re, &s->gb);
516 if (s->codec_id == AV_CODEC_ID_RV10) {
517 /* XXX: should patch encoder too */
518 level = SHOW_SBITS(re, &s->gb, 12);
519 SKIP_COUNTER(re, &s->gb, 12);
520 }else{
521 level = SHOW_UBITS(re, &s->gb, 5);
522 SKIP_CACHE(re, &s->gb, 5);
523 level |= SHOW_SBITS(re, &s->gb, 6)<<5;
524 SKIP_COUNTER(re, &s->gb, 5 + 6);
525 }
526 }
527 }
528 } else {
529 if (SHOW_UBITS(re, &s->gb, 1))
530 level = -level;
531 SKIP_COUNTER(re, &s->gb, 1);
532 }
533 i += run;
534 if (i >= 64){
535 CLOSE_READER(re, &s->gb);
536 // redo update without last flag, revert -1 offset
537 i = i - run + ((run-1)&63) + 1;
538 if (i < 64) {
539 // only last marker, no overrun
540 block[scan_table[i]] = level;
541 break;
542 }
543 if(s->alt_inter_vlc && rl == &ff_h263_rl_inter && !s->mb_intra){
544 //Looks like a hack but no, it's the way it is supposed to work ...
545 rl = &ff_rl_intra_aic;
546 i = 0;
547 s->gb= gb;
548 s->bdsp.clear_block(block);
549 goto retry;
550 }
551 av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d i:%d\n", s->mb_x, s->mb_y, s->mb_intra);
552 return -1;
553 }
554 j = scan_table[i];
555 block[j] = level;
556 }
557 }
558not_coded:
559 if (s->mb_intra && s->h263_aic) {
560 ff_h263_pred_acdc(s, block, n);
561 i = 63;
562 }
563 s->block_last_index[n] = i;
564 return 0;
565}
566
567static int h263_skip_b_part(MpegEncContext *s, int cbp)
568{
569 LOCAL_ALIGNED_16(int16_t, dblock, [64]);
570 int i, mbi;
571 int bli[6];
572
573 /* we have to set s->mb_intra to zero to decode B-part of PB-frame correctly
574 * but real value should be restored in order to be used later (in OBMC condition)
575 */
576 mbi = s->mb_intra;
577 memcpy(bli, s->block_last_index, sizeof(bli));
578 s->mb_intra = 0;
579 for (i = 0; i < 6; i++) {
580 if (h263_decode_block(s, dblock, i, cbp&32) < 0)
581 return -1;
582 cbp+=cbp;
583 }
584 s->mb_intra = mbi;
585 memcpy(s->block_last_index, bli, sizeof(bli));
586 return 0;
587}
588
589static int h263_get_modb(GetBitContext *gb, int pb_frame, int *cbpb)
590{
591 int c, mv = 1;
592
593 if (pb_frame < 3) { // h.263 Annex G and i263 PB-frame
594 c = get_bits1(gb);
595 if (pb_frame == 2 && c)
596 mv = !get_bits1(gb);
597 } else { // h.263 Annex M improved PB-frame
598 mv = get_unary(gb, 0, 4) + 1;
599 c = mv & 1;
600 mv = !!(mv & 2);
601 }
602 if(c)
603 *cbpb = get_bits(gb, 6);
604 return mv;
605}
606
607int ff_h263_decode_mb(MpegEncContext *s,
608 int16_t block[6][64])
609{
610 int cbpc, cbpy, i, cbp, pred_x, pred_y, mx, my, dquant;
611 int16_t *mot_val;
612 const int xy= s->mb_x + s->mb_y * s->mb_stride;
613 int cbpb = 0, pb_mv_count = 0;
614
615 av_assert2(!s->h263_pred);
616
617 if (s->pict_type == AV_PICTURE_TYPE_P) {
618 do{
619 if (get_bits1(&s->gb)) {
620 /* skip mb */
621 s->mb_intra = 0;
622 for(i=0;i<6;i++)
623 s->block_last_index[i] = -1;
624 s->mv_dir = MV_DIR_FORWARD;
625 s->mv_type = MV_TYPE_16X16;
626 s->current_picture.mb_type[xy] = MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
627 s->mv[0][0][0] = 0;
628 s->mv[0][0][1] = 0;
629 s->mb_skipped = !(s->obmc | s->loop_filter);
630 goto end;
631 }
632 cbpc = get_vlc2(&s->gb, ff_h263_inter_MCBPC_vlc.table, INTER_MCBPC_VLC_BITS, 2);
633 if (cbpc < 0){
634 av_log(s->avctx, AV_LOG_ERROR, "cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
635 return -1;
636 }
637 }while(cbpc == 20);
638
639 s->bdsp.clear_blocks(s->block[0]);
640
641 dquant = cbpc & 8;
642 s->mb_intra = ((cbpc & 4) != 0);
643 if (s->mb_intra) goto intra;
644
645 if(s->pb_frame && get_bits1(&s->gb))
646 pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb);
647 cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
648
649 if(s->alt_inter_vlc==0 || (cbpc & 3)!=3)
650 cbpy ^= 0xF;
651
652 cbp = (cbpc & 3) | (cbpy << 2);
653 if (dquant) {
654 h263_decode_dquant(s);
655 }
656
657 s->mv_dir = MV_DIR_FORWARD;
658 if ((cbpc & 16) == 0) {
659 s->current_picture.mb_type[xy] = MB_TYPE_16x16 | MB_TYPE_L0;
660 /* 16x16 motion prediction */
661 s->mv_type = MV_TYPE_16X16;
662 ff_h263_pred_motion(s, 0, 0, &pred_x, &pred_y);
663 if (s->umvplus)
664 mx = h263p_decode_umotion(s, pred_x);
665 else
666 mx = ff_h263_decode_motion(s, pred_x, 1);
667
668 if (mx >= 0xffff)
669 return -1;
670
671 if (s->umvplus)
672 my = h263p_decode_umotion(s, pred_y);
673 else
674 my = ff_h263_decode_motion(s, pred_y, 1);
675
676 if (my >= 0xffff)
677 return -1;
678 s->mv[0][0][0] = mx;
679 s->mv[0][0][1] = my;
680
681 if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
682 skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
683 } else {
684 s->current_picture.mb_type[xy] = MB_TYPE_8x8 | MB_TYPE_L0;
685 s->mv_type = MV_TYPE_8X8;
686 for(i=0;i<4;i++) {
687 mot_val = ff_h263_pred_motion(s, i, 0, &pred_x, &pred_y);
688 if (s->umvplus)
689 mx = h263p_decode_umotion(s, pred_x);
690 else
691 mx = ff_h263_decode_motion(s, pred_x, 1);
692 if (mx >= 0xffff)
693 return -1;
694
695 if (s->umvplus)
696 my = h263p_decode_umotion(s, pred_y);
697 else
698 my = ff_h263_decode_motion(s, pred_y, 1);
699 if (my >= 0xffff)
700 return -1;
701 s->mv[0][i][0] = mx;
702 s->mv[0][i][1] = my;
703 if (s->umvplus && (mx - pred_x) == 1 && (my - pred_y) == 1)
704 skip_bits1(&s->gb); /* Bit stuffing to prevent PSC */
705 mot_val[0] = mx;
706 mot_val[1] = my;
707 }
708 }
709 } else if(s->pict_type==AV_PICTURE_TYPE_B) {
710 int mb_type;
711 const int stride= s->b8_stride;
712 int16_t *mot_val0 = s->current_picture.motion_val[0][2 * (s->mb_x + s->mb_y * stride)];
713 int16_t *mot_val1 = s->current_picture.motion_val[1][2 * (s->mb_x + s->mb_y * stride)];
714// const int mv_xy= s->mb_x + 1 + s->mb_y * s->mb_stride;
715
716 //FIXME ugly
717 mot_val0[0 ]= mot_val0[2 ]= mot_val0[0+2*stride]= mot_val0[2+2*stride]=
718 mot_val0[1 ]= mot_val0[3 ]= mot_val0[1+2*stride]= mot_val0[3+2*stride]=
719 mot_val1[0 ]= mot_val1[2 ]= mot_val1[0+2*stride]= mot_val1[2+2*stride]=
720 mot_val1[1 ]= mot_val1[3 ]= mot_val1[1+2*stride]= mot_val1[3+2*stride]= 0;
721
722 do{
723 mb_type= get_vlc2(&s->gb, h263_mbtype_b_vlc.table, H263_MBTYPE_B_VLC_BITS, 2);
724 if (mb_type < 0){
725 av_log(s->avctx, AV_LOG_ERROR, "b mb_type damaged at %d %d\n", s->mb_x, s->mb_y);
726 return -1;
727 }
728
729 mb_type= h263_mb_type_b_map[ mb_type ];
730 }while(!mb_type);
731
732 s->mb_intra = IS_INTRA(mb_type);
733 if(HAS_CBP(mb_type)){
734 s->bdsp.clear_blocks(s->block[0]);
735 cbpc = get_vlc2(&s->gb, cbpc_b_vlc.table, CBPC_B_VLC_BITS, 1);
736 if(s->mb_intra){
737 dquant = IS_QUANT(mb_type);
738 goto intra;
739 }
740
741 cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
742
743 if (cbpy < 0){
744 av_log(s->avctx, AV_LOG_ERROR, "b cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
745 return -1;
746 }
747
748 if(s->alt_inter_vlc==0 || (cbpc & 3)!=3)
749 cbpy ^= 0xF;
750
751 cbp = (cbpc & 3) | (cbpy << 2);
752 }else
753 cbp=0;
754
755 av_assert2(!s->mb_intra);
756
757 if(IS_QUANT(mb_type)){
758 h263_decode_dquant(s);
759 }
760
761 if(IS_DIRECT(mb_type)){
762 s->mv_dir = MV_DIR_FORWARD | MV_DIR_BACKWARD | MV_DIRECT;
763 mb_type |= ff_mpeg4_set_direct_mv(s, 0, 0);
764 }else{
765 s->mv_dir = 0;
766 s->mv_type= MV_TYPE_16X16;
767//FIXME UMV
768
769 if(USES_LIST(mb_type, 0)){
770 int16_t *mot_val= ff_h263_pred_motion(s, 0, 0, &mx, &my);
771 s->mv_dir = MV_DIR_FORWARD;
772
773 mx = ff_h263_decode_motion(s, mx, 1);
774 my = ff_h263_decode_motion(s, my, 1);
775
776 s->mv[0][0][0] = mx;
777 s->mv[0][0][1] = my;
778 mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
779 mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
780 }
781
782 if(USES_LIST(mb_type, 1)){
783 int16_t *mot_val= ff_h263_pred_motion(s, 0, 1, &mx, &my);
784 s->mv_dir |= MV_DIR_BACKWARD;
785
786 mx = ff_h263_decode_motion(s, mx, 1);
787 my = ff_h263_decode_motion(s, my, 1);
788
789 s->mv[1][0][0] = mx;
790 s->mv[1][0][1] = my;
791 mot_val[0 ]= mot_val[2 ]= mot_val[0+2*stride]= mot_val[2+2*stride]= mx;
792 mot_val[1 ]= mot_val[3 ]= mot_val[1+2*stride]= mot_val[3+2*stride]= my;
793 }
794 }
795
796 s->current_picture.mb_type[xy] = mb_type;
797 } else { /* I-Frame */
798 do{
799 cbpc = get_vlc2(&s->gb, ff_h263_intra_MCBPC_vlc.table, INTRA_MCBPC_VLC_BITS, 2);
800 if (cbpc < 0){
801 av_log(s->avctx, AV_LOG_ERROR, "I cbpc damaged at %d %d\n", s->mb_x, s->mb_y);
802 return -1;
803 }
804 }while(cbpc == 8);
805
806 s->bdsp.clear_blocks(s->block[0]);
807
808 dquant = cbpc & 4;
809 s->mb_intra = 1;
810intra:
811 s->current_picture.mb_type[xy] = MB_TYPE_INTRA;
812 if (s->h263_aic) {
813 s->ac_pred = get_bits1(&s->gb);
814 if(s->ac_pred){
815 s->current_picture.mb_type[xy] = MB_TYPE_INTRA | MB_TYPE_ACPRED;
816
817 s->h263_aic_dir = get_bits1(&s->gb);
818 }
819 }else
820 s->ac_pred = 0;
821
822 if(s->pb_frame && get_bits1(&s->gb))
823 pb_mv_count = h263_get_modb(&s->gb, s->pb_frame, &cbpb);
824 cbpy = get_vlc2(&s->gb, ff_h263_cbpy_vlc.table, CBPY_VLC_BITS, 1);
825 if(cbpy<0){
826 av_log(s->avctx, AV_LOG_ERROR, "I cbpy damaged at %d %d\n", s->mb_x, s->mb_y);
827 return -1;
828 }
829 cbp = (cbpc & 3) | (cbpy << 2);
830 if (dquant) {
831 h263_decode_dquant(s);
832 }
833
834 pb_mv_count += !!s->pb_frame;
835 }
836
837 while(pb_mv_count--){
838 ff_h263_decode_motion(s, 0, 1);
839 ff_h263_decode_motion(s, 0, 1);
840 }
841
842 /* decode each block */
843 for (i = 0; i < 6; i++) {
844 if (h263_decode_block(s, block[i], i, cbp&32) < 0)
845 return -1;
846 cbp+=cbp;
847 }
848
849 if(s->pb_frame && h263_skip_b_part(s, cbpb) < 0)
850 return -1;
851 if(s->obmc && !s->mb_intra){
852 if(s->pict_type == AV_PICTURE_TYPE_P && s->mb_x+1<s->mb_width && s->mb_num_left != 1)
853 preview_obmc(s);
854 }
855end:
856
857 /* per-MB end of slice check */
858 {
859 int v= show_bits(&s->gb, 16);
860
861 if (get_bits_left(&s->gb) < 16) {
862 v >>= 16 - get_bits_left(&s->gb);
863 }
864
865 if(v==0)
866 return SLICE_END;
867 }
868
869 return SLICE_OK;
870}
871
872/* most is hardcoded. should extend to handle all h263 streams */
873int ff_h263_decode_picture_header(MpegEncContext *s)
874{
875 int format, width, height, i;
876 uint32_t startcode;
877
878 align_get_bits(&s->gb);
879
880 if (show_bits(&s->gb, 2) == 2 && s->avctx->frame_number == 0) {
881 av_log(s->avctx, AV_LOG_WARNING, "Header looks like RTP instead of H.263\n");
882 }
883
884 startcode= get_bits(&s->gb, 22-8);
885
886 for(i= get_bits_left(&s->gb); i>24; i-=8) {
887 startcode = ((startcode << 8) | get_bits(&s->gb, 8)) & 0x003FFFFF;
888
889 if(startcode == 0x20)
890 break;
891 }
892
893 if (startcode != 0x20) {
894 av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
895 return -1;
896 }
897 /* temporal reference */
898 i = get_bits(&s->gb, 8); /* picture timestamp */
899 if( (s->picture_number&~0xFF)+i < s->picture_number)
900 i+= 256;
901 s->picture_number= (s->picture_number&~0xFF) + i;
902
903 /* PTYPE starts here */
904 if (get_bits1(&s->gb) != 1) {
905 /* marker */
906 av_log(s->avctx, AV_LOG_ERROR, "Bad marker\n");
907 return -1;
908 }
909 if (get_bits1(&s->gb) != 0) {
910 av_log(s->avctx, AV_LOG_ERROR, "Bad H263 id\n");
911 return -1; /* h263 id */
912 }
913 skip_bits1(&s->gb); /* split screen off */
914 skip_bits1(&s->gb); /* camera off */
915 skip_bits1(&s->gb); /* freeze picture release off */
916
917 format = get_bits(&s->gb, 3);
918 /*
919 0 forbidden
920 1 sub-QCIF
921 10 QCIF
922 7 extended PTYPE (PLUSPTYPE)
923 */
924
925 if (format != 7 && format != 6) {
926 s->h263_plus = 0;
927 /* H.263v1 */
928 width = ff_h263_format[format][0];
929 height = ff_h263_format[format][1];
930 if (!width)
931 return -1;
932
933 s->pict_type = AV_PICTURE_TYPE_I + get_bits1(&s->gb);
934
935 s->h263_long_vectors = get_bits1(&s->gb);
936
937 if (get_bits1(&s->gb) != 0) {
938 av_log(s->avctx, AV_LOG_ERROR, "H263 SAC not supported\n");
939 return -1; /* SAC: off */
940 }
941 s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */
942 s->unrestricted_mv = s->h263_long_vectors || s->obmc;
943
944 s->pb_frame = get_bits1(&s->gb);
945 s->chroma_qscale= s->qscale = get_bits(&s->gb, 5);
946 skip_bits1(&s->gb); /* Continuous Presence Multipoint mode: off */
947
948 s->width = width;
949 s->height = height;
950 s->avctx->sample_aspect_ratio= (AVRational){12,11};
951 s->avctx->time_base= (AVRational){1001, 30000};
952 } else {
953 int ufep;
954
955 /* H.263v2 */
956 s->h263_plus = 1;
957 ufep = get_bits(&s->gb, 3); /* Update Full Extended PTYPE */
958
959 /* ufep other than 0 and 1 are reserved */
960 if (ufep == 1) {
961 /* OPPTYPE */
962 format = get_bits(&s->gb, 3);
963 av_dlog(s->avctx, "ufep=1, format: %d\n", format);
964 s->custom_pcf= get_bits1(&s->gb);
965 s->umvplus = get_bits1(&s->gb); /* Unrestricted Motion Vector */
966 if (get_bits1(&s->gb) != 0) {
967 av_log(s->avctx, AV_LOG_ERROR, "Syntax-based Arithmetic Coding (SAC) not supported\n");
968 }
969 s->obmc= get_bits1(&s->gb); /* Advanced prediction mode */
970 s->h263_aic = get_bits1(&s->gb); /* Advanced Intra Coding (AIC) */
971 s->loop_filter= get_bits1(&s->gb);
972 s->unrestricted_mv = s->umvplus || s->obmc || s->loop_filter;
973 if(s->avctx->lowres)
974 s->loop_filter = 0;
975
976 s->h263_slice_structured= get_bits1(&s->gb);
977 if (get_bits1(&s->gb) != 0) {
978 av_log(s->avctx, AV_LOG_ERROR, "Reference Picture Selection not supported\n");
979 }
980 if (get_bits1(&s->gb) != 0) {
981 av_log(s->avctx, AV_LOG_ERROR, "Independent Segment Decoding not supported\n");
982 }
983 s->alt_inter_vlc= get_bits1(&s->gb);
984 s->modified_quant= get_bits1(&s->gb);
985 if(s->modified_quant)
986 s->chroma_qscale_table= ff_h263_chroma_qscale_table;
987
988 skip_bits(&s->gb, 1); /* Prevent start code emulation */
989
990 skip_bits(&s->gb, 3); /* Reserved */
991 } else if (ufep != 0) {
992 av_log(s->avctx, AV_LOG_ERROR, "Bad UFEP type (%d)\n", ufep);
993 return -1;
994 }
995
996 /* MPPTYPE */
997 s->pict_type = get_bits(&s->gb, 3);
998 switch(s->pict_type){
999 case 0: s->pict_type= AV_PICTURE_TYPE_I;break;
1000 case 1: s->pict_type= AV_PICTURE_TYPE_P;break;
1001 case 2: s->pict_type= AV_PICTURE_TYPE_P;s->pb_frame = 3;break;
1002 case 3: s->pict_type= AV_PICTURE_TYPE_B;break;
1003 case 7: s->pict_type= AV_PICTURE_TYPE_I;break; //ZYGO
1004 default:
1005 return -1;
1006 }
1007 skip_bits(&s->gb, 2);
1008 s->no_rounding = get_bits1(&s->gb);
1009 skip_bits(&s->gb, 4);
1010
1011 /* Get the picture dimensions */
1012 if (ufep) {
1013 if (format == 6) {
1014 /* Custom Picture Format (CPFMT) */
1015 s->aspect_ratio_info = get_bits(&s->gb, 4);
1016 av_dlog(s->avctx, "aspect: %d\n", s->aspect_ratio_info);
1017 /* aspect ratios:
1018 0 - forbidden
1019 1 - 1:1
1020 2 - 12:11 (CIF 4:3)
1021 3 - 10:11 (525-type 4:3)
1022 4 - 16:11 (CIF 16:9)
1023 5 - 40:33 (525-type 16:9)
1024 6-14 - reserved
1025 */
1026 width = (get_bits(&s->gb, 9) + 1) * 4;
1027 skip_bits1(&s->gb);
1028 height = get_bits(&s->gb, 9) * 4;
1029 av_dlog(s->avctx, "\nH.263+ Custom picture: %dx%d\n",width,height);
1030 if (s->aspect_ratio_info == FF_ASPECT_EXTENDED) {
1031 /* aspected dimensions */
1032 s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 8);
1033 s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 8);
1034 }else{
1035 s->avctx->sample_aspect_ratio= ff_h263_pixel_aspect[s->aspect_ratio_info];
1036 }
1037 } else {
1038 width = ff_h263_format[format][0];
1039 height = ff_h263_format[format][1];
1040 s->avctx->sample_aspect_ratio= (AVRational){12,11};
1041 }
1042 s->avctx->sample_aspect_ratio.den <<= s->ehc_mode;
1043 if ((width == 0) || (height == 0))
1044 return -1;
1045 s->width = width;
1046 s->height = height;
1047
1048 if(s->custom_pcf){
1049 int gcd;
1050 s->avctx->time_base.den= 1800000;
1051 s->avctx->time_base.num= 1000 + get_bits1(&s->gb);
1052 s->avctx->time_base.num*= get_bits(&s->gb, 7);
1053 if(s->avctx->time_base.num == 0){
1054 av_log(s, AV_LOG_ERROR, "zero framerate\n");
1055 return -1;
1056 }
1057 gcd= av_gcd(s->avctx->time_base.den, s->avctx->time_base.num);
1058 s->avctx->time_base.den /= gcd;
1059 s->avctx->time_base.num /= gcd;
1060 }else{
1061 s->avctx->time_base= (AVRational){1001, 30000};
1062 }
1063 }
1064
1065 if(s->custom_pcf){
1066 skip_bits(&s->gb, 2); //extended Temporal reference
1067 }
1068
1069 if (ufep) {
1070 if (s->umvplus) {
1071 if(get_bits1(&s->gb)==0) /* Unlimited Unrestricted Motion Vectors Indicator (UUI) */
1072 skip_bits1(&s->gb);
1073 }
1074 if(s->h263_slice_structured){
1075 if (get_bits1(&s->gb) != 0) {
1076 av_log(s->avctx, AV_LOG_ERROR, "rectangular slices not supported\n");
1077 }
1078 if (get_bits1(&s->gb) != 0) {
1079 av_log(s->avctx, AV_LOG_ERROR, "unordered slices not supported\n");
1080 }
1081 }
1082 }
1083
1084 s->qscale = get_bits(&s->gb, 5);
1085 }
1086
1087 if (s->width == 0 || s->height == 0) {
1088 av_log(s->avctx, AV_LOG_ERROR, "dimensions 0\n");
1089 return -1;
1090 }
1091 s->mb_width = (s->width + 15) / 16;
1092 s->mb_height = (s->height + 15) / 16;
1093 s->mb_num = s->mb_width * s->mb_height;
1094
1095 if (s->pb_frame) {
1096 skip_bits(&s->gb, 3); /* Temporal reference for B-pictures */
1097 if (s->custom_pcf)
1098 skip_bits(&s->gb, 2); //extended Temporal reference
1099 skip_bits(&s->gb, 2); /* Quantization information for B-pictures */
1100 }
1101
1102 if (s->pict_type!=AV_PICTURE_TYPE_B) {
1103 s->time = s->picture_number;
1104 s->pp_time = s->time - s->last_non_b_time;
1105 s->last_non_b_time = s->time;
1106 }else{
1107 s->time = s->picture_number;
1108 s->pb_time = s->pp_time - (s->last_non_b_time - s->time);
1109 if (s->pp_time <=s->pb_time ||
1110 s->pp_time <= s->pp_time - s->pb_time ||
1111 s->pp_time <= 0){
1112 s->pp_time = 2;
1113 s->pb_time = 1;
1114 }
1115 ff_mpeg4_init_direct_mv(s);
1116 }
1117
1118 /* PEI */
1119 if (skip_1stop_8data_bits(&s->gb) < 0)
1120 return AVERROR_INVALIDDATA;
1121
1122 if(s->h263_slice_structured){
1123 if (get_bits1(&s->gb) != 1) {
1124 av_log(s->avctx, AV_LOG_ERROR, "SEPB1 marker missing\n");
1125 return -1;
1126 }
1127
1128 ff_h263_decode_mba(s);
1129
1130 if (get_bits1(&s->gb) != 1) {
1131 av_log(s->avctx, AV_LOG_ERROR, "SEPB2 marker missing\n");
1132 return -1;
1133 }
1134 }
1135 s->f_code = 1;
1136
1137 if(s->h263_aic){
1138 s->y_dc_scale_table=
1139 s->c_dc_scale_table= ff_aic_dc_scale_table;
1140 }else{
1141 s->y_dc_scale_table=
1142 s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
1143 }
1144
1145 ff_h263_show_pict_info(s);
1146 if (s->pict_type == AV_PICTURE_TYPE_I && s->codec_tag == AV_RL32("ZYGO") && get_bits_left(&s->gb) >= 85 + 13*3*16 + 50){
1147 int i,j;
1148 for(i=0; i<85; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb));
1149 av_log(s->avctx, AV_LOG_DEBUG, "\n");
1150 for(i=0; i<13; i++){
1151 for(j=0; j<3; j++){
1152 int v= get_bits(&s->gb, 8);
1153 v |= get_sbits(&s->gb, 8)<<8;
1154 av_log(s->avctx, AV_LOG_DEBUG, " %5d", v);
1155 }
1156 av_log(s->avctx, AV_LOG_DEBUG, "\n");
1157 }
1158 for(i=0; i<50; i++) av_log(s->avctx, AV_LOG_DEBUG, "%d", get_bits1(&s->gb));
1159 }
1160
1161 return 0;
1162}
ffmpeg Piment Noir Debian package repository