2 * MPEG1 encoder / MPEG2 decoder
3 * Copyright (c) 2000,2001 Fabrice Bellard.
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include "mpegvideo.h"
24 #include "mpeg12data.h"
27 #define PRINT_QP(a, b) {}
29 #define PRINT_QP(a, b) printf(a, b)
33 #define SEQ_END_CODE 0x000001b7
34 #define SEQ_START_CODE 0x000001b3
35 #define GOP_START_CODE 0x000001b8
36 #define PICTURE_START_CODE 0x00000100
37 #define SLICE_MIN_START_CODE 0x00000101
38 #define SLICE_MAX_START_CODE 0x000001af
39 #define EXT_START_CODE 0x000001b5
40 #define USER_START_CODE 0x000001b2
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 void mpeg1_encode_block(MpegEncContext *s,
53 static void mpeg1_encode_motion(MpegEncContext *s, int val);
54 static void mpeg1_skip_picture(MpegEncContext *s, int pict_num);
55 static int mpeg1_decode_block(MpegEncContext *s,
58 static int mpeg2_decode_block_non_intra(MpegEncContext *s,
61 static int mpeg2_decode_block_intra(MpegEncContext *s,
64 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred);
66 static UINT16 mv_penalty[MAX_FCODE+1][MAX_MV*2+1];
67 static UINT8 fcode_tab[MAX_MV*2+1];
69 static void init_2d_vlc_rl(RLTable *rl)
73 init_vlc(&rl->vlc, TEX_VLC_BITS, rl->n + 2,
74 &rl->table_vlc[0][1], 4, 2,
75 &rl->table_vlc[0][0], 4, 2);
78 rl->rl_vlc[0]= av_malloc(rl->vlc.table_size*sizeof(RL_VLC_ELEM));
79 for(i=0; i<rl->vlc.table_size; i++){
80 int code= rl->vlc.table[i][0];
81 int len = rl->vlc.table[i][1];
84 if(len==0){ // illegal code
87 }else if(len<0){ //more bits needed
91 if(code==rl->n){ //esc
94 }else if(code==rl->n+1){ //eob
98 run= rl->table_run [code] + 1;
99 level= rl->table_level[code];
102 rl->rl_vlc[0][i].len= len;
103 rl->rl_vlc[0][i].level= level;
104 rl->rl_vlc[0][i].run= run;
109 static void put_header(MpegEncContext *s, int header)
111 align_put_bits(&s->pb);
112 put_bits(&s->pb, 16, header>>16);
113 put_bits(&s->pb, 16, header&0xFFFF);
116 /* put sequence header if needed */
117 static void mpeg1_encode_sequence_header(MpegEncContext *s)
119 unsigned int vbv_buffer_size;
124 if (s->picture_in_gop_number == 0) {
125 /* mpeg1 header repeated every gop */
126 put_header(s, SEQ_START_CODE);
128 /* search closest frame rate */
131 s->frame_rate_index = 0;
134 d = abs(s->frame_rate - frame_rate_tab[i]);
137 s->frame_rate_index = i;
142 put_bits(&s->pb, 12, s->width);
143 put_bits(&s->pb, 12, s->height);
144 put_bits(&s->pb, 4, 1); /* 1/1 aspect ratio */
145 put_bits(&s->pb, 4, s->frame_rate_index);
146 v = s->bit_rate / 400;
149 put_bits(&s->pb, 18, v);
150 put_bits(&s->pb, 1, 1); /* marker */
152 if(s->avctx->rc_buffer_size)
153 vbv_buffer_size = s->avctx->rc_buffer_size;
155 /* VBV calculation: Scaled so that a VCD has the proper VBV size of 40 kilobytes */
156 vbv_buffer_size = (( 20 * s->bit_rate) / (1151929 / 2)) * 8 * 1024;
157 put_bits(&s->pb, 10, (vbv_buffer_size + 16383) / 16384);
158 put_bits(&s->pb, 1, 1); /* constrained parameter flag */
159 put_bits(&s->pb, 1, 0); /* no custom intra matrix */
160 put_bits(&s->pb, 1, 0); /* no custom non intra matrix */
162 put_header(s, GOP_START_CODE);
163 put_bits(&s->pb, 1, 0); /* do drop frame */
164 /* time code : we must convert from the real frame rate to a
165 fake mpeg frame rate in case of low frame rate */
166 fps = frame_rate_tab[s->frame_rate_index];
167 time_code = (INT64)s->fake_picture_number * FRAME_RATE_BASE;
168 s->gop_picture_number = s->fake_picture_number;
169 put_bits(&s->pb, 5, (UINT32)((time_code / (fps * 3600)) % 24));
170 put_bits(&s->pb, 6, (UINT32)((time_code / (fps * 60)) % 60));
171 put_bits(&s->pb, 1, 1);
172 put_bits(&s->pb, 6, (UINT32)((time_code / fps) % 60));
173 put_bits(&s->pb, 6, (UINT32)((time_code % fps) / FRAME_RATE_BASE));
174 put_bits(&s->pb, 1, 1); /* closed gop */
175 put_bits(&s->pb, 1, 0); /* broken link */
178 if (s->frame_rate < (24 * FRAME_RATE_BASE) && s->picture_number > 0) {
179 /* insert empty P pictures to slow down to the desired
180 frame rate. Each fake pictures takes about 20 bytes */
181 fps = frame_rate_tab[s->frame_rate_index];
182 n = (((INT64)s->picture_number * fps) / s->frame_rate) - 1;
183 while (s->fake_picture_number < n) {
184 mpeg1_skip_picture(s, s->fake_picture_number -
185 s->gop_picture_number);
186 s->fake_picture_number++;
193 /* insert a fake P picture */
194 static void mpeg1_skip_picture(MpegEncContext *s, int pict_num)
196 unsigned int mb_incr;
198 /* mpeg1 picture header */
199 put_header(s, PICTURE_START_CODE);
200 /* temporal reference */
201 put_bits(&s->pb, 10, pict_num & 0x3ff);
203 put_bits(&s->pb, 3, P_TYPE);
204 put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
206 put_bits(&s->pb, 1, 1); /* integer coordinates */
207 put_bits(&s->pb, 3, 1); /* forward_f_code */
209 put_bits(&s->pb, 1, 0); /* extra bit picture */
212 put_header(s, SLICE_MIN_START_CODE);
213 put_bits(&s->pb, 5, 1); /* quantizer scale */
214 put_bits(&s->pb, 1, 0); /* slice extra information */
217 put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1],
218 mbAddrIncrTable[mb_incr - 1][0]);
220 /* empty macroblock */
221 put_bits(&s->pb, 3, 1); /* motion only */
223 /* zero motion x & y */
224 put_bits(&s->pb, 1, 1);
225 put_bits(&s->pb, 1, 1);
227 /* output a number of empty slice */
228 mb_incr = s->mb_width * s->mb_height - 1;
229 while (mb_incr > 33) {
230 put_bits(&s->pb, 11, 0x008);
233 put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1],
234 mbAddrIncrTable[mb_incr - 1][0]);
236 /* empty macroblock */
237 put_bits(&s->pb, 3, 1); /* motion only */
239 /* zero motion x & y */
240 put_bits(&s->pb, 1, 1);
241 put_bits(&s->pb, 1, 1);
244 static void common_init(MpegEncContext *s)
247 s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
250 void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
252 mpeg1_encode_sequence_header(s);
254 /* mpeg1 picture header */
255 put_header(s, PICTURE_START_CODE);
256 /* temporal reference */
257 put_bits(&s->pb, 10, (s->fake_picture_number -
258 s->gop_picture_number) & 0x3ff);
259 s->fake_picture_number++;
261 put_bits(&s->pb, 3, s->pict_type);
262 put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
264 if (s->pict_type == P_TYPE) {
265 put_bits(&s->pb, 1, 0); /* half pel coordinates */
266 put_bits(&s->pb, 3, s->f_code); /* forward_f_code */
269 put_bits(&s->pb, 1, 0); /* extra bit picture */
272 put_header(s, SLICE_MIN_START_CODE);
273 put_bits(&s->pb, 5, s->qscale); /* quantizer scale */
274 put_bits(&s->pb, 1, 0); /* slice extra information */
277 void mpeg1_encode_mb(MpegEncContext *s,
278 DCTELEM block[6][64],
279 int motion_x, int motion_y)
281 int mb_incr, i, cbp, mb_x, mb_y;
289 if (s->block_last_index[i] >= 0)
293 /* skip macroblock, except if first or last macroblock of a slice */
294 if ((cbp | motion_x | motion_y) == 0 &&
295 (!((mb_x | mb_y) == 0 ||
296 (mb_x == s->mb_width - 1 && mb_y == s->mb_height - 1)))) {
298 s->qscale -= s->dquant;
301 mb_incr = s->mb_incr;
303 while (mb_incr > 33) {
304 put_bits(&s->pb, 11, 0x008);
307 put_bits(&s->pb, mbAddrIncrTable[mb_incr - 1][1],
308 mbAddrIncrTable[mb_incr - 1][0]);
310 if (s->pict_type == I_TYPE) {
311 if(s->dquant && cbp){
312 put_bits(&s->pb, 2, 1); /* macroblock_type : macroblock_quant = 1 */
313 put_bits(&s->pb, 5, s->qscale);
315 put_bits(&s->pb, 1, 1); /* macroblock_type : macroblock_quant = 0 */
316 s->qscale -= s->dquant;
320 if(s->dquant && cbp){
321 put_bits(&s->pb, 6, 0x01);
322 put_bits(&s->pb, 5, s->qscale);
324 put_bits(&s->pb, 5, 0x03);
325 s->qscale -= s->dquant;
329 if (motion_x == 0 && motion_y == 0) {
331 put_bits(&s->pb, 5, 1); /* macroblock_pattern & quant */
332 put_bits(&s->pb, 5, s->qscale);
334 put_bits(&s->pb, 2, 1); /* macroblock_pattern only */
336 put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
339 put_bits(&s->pb, 5, 2); /* motion + cbp */
340 put_bits(&s->pb, 5, s->qscale);
342 put_bits(&s->pb, 1, 1); /* motion + cbp */
344 mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0]);
345 mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1]);
346 put_bits(&s->pb, mbPatTable[cbp - 1][1], mbPatTable[cbp - 1][0]);
349 put_bits(&s->pb, 3, 1); /* motion only */
350 mpeg1_encode_motion(s, motion_x - s->last_mv[0][0][0]);
351 mpeg1_encode_motion(s, motion_y - s->last_mv[0][0][1]);
352 s->qscale -= s->dquant;
357 if (cbp & (1 << (5 - i))) {
358 mpeg1_encode_block(s, block[i], i);
363 s->last_mv[0][0][0] = motion_x;
364 s->last_mv[0][0][1] = motion_y;
367 static void mpeg1_encode_motion(MpegEncContext *s, int val)
369 int code, bit_size, l, m, bits, range, sign;
375 mbMotionVectorTable[0][1],
376 mbMotionVectorTable[0][0]);
378 bit_size = s->f_code - 1;
379 range = 1 << bit_size;
380 /* modulo encoding */
385 } else if (val >= l) {
391 code = (val >> bit_size) + 1;
392 bits = val & (range - 1);
397 code = (val >> bit_size) + 1;
398 bits = val & (range - 1);
402 mbMotionVectorTable[code][1],
403 mbMotionVectorTable[code][0]);
404 put_bits(&s->pb, 1, sign);
406 put_bits(&s->pb, bit_size, bits);
411 void ff_mpeg1_encode_init(MpegEncContext *s)
427 mpeg1_max_level[0][i]= rl_mpeg1.max_level[0][i];
428 mpeg1_index_run[0][i]= rl_mpeg1.index_run[0][i];
431 /* build unified dc encoding tables */
432 for(i=-255; i<256; i++)
440 index = vlc_dc_table[adiff];
442 bits= vlc_dc_lum_bits[index] + index;
443 code= (vlc_dc_lum_code[index]<<index) + (diff & ((1 << index) - 1));
444 mpeg1_lum_dc_uni[i+255]= bits + (code<<8);
446 bits= vlc_dc_chroma_bits[index] + index;
447 code= (vlc_dc_chroma_code[index]<<index) + (diff & ((1 << index) - 1));
448 mpeg1_chr_dc_uni[i+255]= bits + (code<<8);
451 for(f_code=1; f_code<=MAX_FCODE; f_code++){
452 for(mv=-MAX_MV; mv<=MAX_MV; mv++){
455 if(mv==0) len= mbMotionVectorTable[0][1];
457 int val, bit_size, range, code;
459 bit_size = s->f_code - 1;
460 range = 1 << bit_size;
466 code = (val >> bit_size) + 1;
468 len= mbMotionVectorTable[code][1] + 1 + bit_size;
470 len= mbMotionVectorTable[16][1] + 2 + bit_size;
474 mv_penalty[f_code][mv+MAX_MV]= len;
479 for(f_code=MAX_FCODE; f_code>0; f_code--){
480 for(mv=-(8<<f_code); mv<(8<<f_code); mv++){
481 fcode_tab[mv+MAX_MV]= f_code;
485 s->mv_penalty= mv_penalty;
486 s->fcode_tab= fcode_tab;
489 s->intra_quant_bias= 3<<(QUANT_BIAS_SHIFT-3); //(a + x*3/8)/x
490 s->inter_quant_bias= 0;
493 static inline void encode_dc(MpegEncContext *s, int diff, int component)
495 if (component == 0) {
498 mpeg1_lum_dc_uni[diff+255]&0xFF,
499 mpeg1_lum_dc_uni[diff+255]>>8);
503 mpeg1_chr_dc_uni[diff+255]&0xFF,
504 mpeg1_chr_dc_uni[diff+255]>>8);
508 static void mpeg1_encode_block(MpegEncContext *s,
512 int alevel, level, last_non_zero, dc, diff, i, j, run, last_index, sign;
514 // RLTable *rl = &rl_mpeg1;
516 last_index = s->block_last_index[n];
520 component = (n <= 3 ? 0 : n - 4 + 1);
521 dc = block[0]; /* overflow is impossible */
522 diff = dc - s->last_dc[component];
523 encode_dc(s, diff, component);
524 s->last_dc[component] = dc;
527 /* encode the first coefficient : needs to be done here because
528 it is handled slightly differently */
530 if (abs(level) == 1) {
531 code = ((UINT32)level >> 31); /* the sign bit */
532 put_bits(&s->pb, 2, code | 0x02);
541 /* now quantify & encode AC coefs */
542 last_non_zero = i - 1;
544 for(;i<=last_index;i++) {
545 j = zigzag_direct[i];
550 dprintf("level[%d]=%d\n", i, level);
552 /* encode using VLC */
554 run = i - last_non_zero - 1;
564 : "=&r" (alevel), "=&r" (sign)
575 // code = get_rl_index(rl, 0, run, alevel);
576 if (alevel > mpeg1_max_level[0][run])
579 code= mpeg1_index_run[0][run] + alevel - 1;
581 if (code < 111 /* rl->n */) {
582 /* store the vlc & sign at once */
583 put_bits(&s->pb, mpeg1_vlc[code][1]+1, (mpeg1_vlc[code][0]<<1) + sign);
585 /* escape seems to be pretty rare <5% so i dont optimize it */
586 put_bits(&s->pb, mpeg1_vlc[111/*rl->n*/][1], mpeg1_vlc[111/*rl->n*/][0]);
587 /* escape: only clip in this case */
588 put_bits(&s->pb, 6, run);
590 put_bits(&s->pb, 8, level & 0xff);
593 put_bits(&s->pb, 16, 0x8001 + level + 255);
595 put_bits(&s->pb, 16, level & 0xffff);
603 put_bits(&s->pb, 2, 0x2);
606 /******************************************/
609 static VLC dc_lum_vlc;
610 static VLC dc_chroma_vlc;
612 static VLC mbincr_vlc;
613 static VLC mb_ptype_vlc;
614 static VLC mb_btype_vlc;
615 static VLC mb_pat_vlc;
617 static void init_vlcs(MpegEncContext *s)
624 init_vlc(&dc_lum_vlc, DC_VLC_BITS, 12,
625 vlc_dc_lum_bits, 1, 1,
626 vlc_dc_lum_code, 2, 2);
627 init_vlc(&dc_chroma_vlc, DC_VLC_BITS, 12,
628 vlc_dc_chroma_bits, 1, 1,
629 vlc_dc_chroma_code, 2, 2);
630 init_vlc(&mv_vlc, MV_VLC_BITS, 17,
631 &mbMotionVectorTable[0][1], 2, 1,
632 &mbMotionVectorTable[0][0], 2, 1);
633 init_vlc(&mbincr_vlc, MBINCR_VLC_BITS, 35,
634 &mbAddrIncrTable[0][1], 2, 1,
635 &mbAddrIncrTable[0][0], 2, 1);
636 init_vlc(&mb_pat_vlc, MB_PAT_VLC_BITS, 63,
637 &mbPatTable[0][1], 2, 1,
638 &mbPatTable[0][0], 2, 1);
640 init_vlc(&mb_ptype_vlc, MB_PTYPE_VLC_BITS, 32,
641 &table_mb_ptype[0][1], 2, 1,
642 &table_mb_ptype[0][0], 2, 1);
643 init_vlc(&mb_btype_vlc, MB_BTYPE_VLC_BITS, 32,
644 &table_mb_btype[0][1], 2, 1,
645 &table_mb_btype[0][0], 2, 1);
649 init_2d_vlc_rl(&rl_mpeg1);
650 init_2d_vlc_rl(&rl_mpeg2);
654 static inline int get_dmv(MpegEncContext *s)
656 if(get_bits1(&s->gb))
657 return 1 - (get_bits1(&s->gb) << 1);
662 static inline int get_qscale(MpegEncContext *s)
666 if (s->q_scale_type) {
667 qscale = non_linear_qscale[get_bits(&s->gb, 5)];
669 qscale = get_bits(&s->gb, 5) << 1;
672 /* for mpeg1, we use the generic unquant code */
673 qscale = get_bits(&s->gb, 5);
678 /* motion type (for mpeg2) */
684 static int mpeg_decode_mb(MpegEncContext *s,
685 DCTELEM block[6][64])
687 int i, j, k, cbp, val, code, mb_type, motion_type;
689 /* skip mb handling */
690 if (s->mb_incr == 0) {
691 /* read again increment */
694 code = get_vlc2(&s->gb, mbincr_vlc.table, MBINCR_VLC_BITS, 2);
696 return 1; /* error = end of slice */
701 /* otherwise, stuffing, nothing to do */
708 if(s->mb_x==-1 /* first MB in a slice */ && s->mb_incr>1){
709 s->mb_x+= (s->mb_incr - 1) % s->mb_width;
710 s->mb_y+= (s->mb_incr - 1) / s->mb_width;
714 if (++s->mb_x >= s->mb_width) {
716 if (s->mb_y >= (s->mb_height - 1)){
717 fprintf(stderr, "slice too long\n");
722 dprintf("decode_mb: x=%d y=%d\n", s->mb_x, s->mb_y);
724 if (--s->mb_incr != 0) {
728 s->block_last_index[i] = -1;
729 s->mv_type = MV_TYPE_16X16;
730 if (s->pict_type == P_TYPE) {
731 /* if P type, zero motion vector is implied */
732 s->mv_dir = MV_DIR_FORWARD;
733 s->mv[0][0][0] = s->mv[0][0][1] = 0;
734 s->last_mv[0][0][0] = s->last_mv[0][0][1] = 0;
735 s->last_mv[0][1][0] = s->last_mv[0][1][1] = 0;
737 /* if B type, reuse previous vectors and directions */
738 s->mv[0][0][0] = s->last_mv[0][0][0];
739 s->mv[0][0][1] = s->last_mv[0][0][1];
740 s->mv[1][0][0] = s->last_mv[1][0][0];
741 s->mv[1][0][1] = s->last_mv[1][0][1];
747 switch(s->pict_type) {
750 if (get_bits1(&s->gb) == 0) {
751 if (get_bits1(&s->gb) == 0)
753 mb_type = MB_QUANT | MB_INTRA;
759 mb_type = get_vlc2(&s->gb, mb_ptype_vlc.table, MB_PTYPE_VLC_BITS, 1);
761 fprintf(stderr, "invalid mb type in P Frame at %d %d\n", s->mb_x, s->mb_y);
766 mb_type = get_vlc2(&s->gb, mb_btype_vlc.table, MB_BTYPE_VLC_BITS, 1);
768 fprintf(stderr, "invalid mb type in B Frame at %d %d\n", s->mb_x, s->mb_y);
773 dprintf("mb_type=%x\n", mb_type);
774 motion_type = 0; /* avoid warning */
775 if (mb_type & (MB_FOR|MB_BACK)) {
776 /* get additionnal motion vector type */
777 if (s->picture_structure == PICT_FRAME && s->frame_pred_frame_dct)
778 motion_type = MT_FRAME;
780 motion_type = get_bits(&s->gb, 2);
782 /* compute dct type */
783 if (s->picture_structure == PICT_FRAME &&
784 !s->frame_pred_frame_dct &&
785 (mb_type & (MB_PAT | MB_INTRA))) {
786 s->interlaced_dct = get_bits1(&s->gb);
788 if (s->interlaced_dct)
789 printf("interlaced_dct\n");
792 s->interlaced_dct = 0; /* frame based */
795 if (mb_type & MB_QUANT) {
796 s->qscale = get_qscale(s);
798 if (mb_type & MB_INTRA) {
799 if (s->concealment_motion_vectors) {
800 /* just parse them */
801 if (s->picture_structure != PICT_FRAME)
802 skip_bits1(&s->gb); /* field select */
803 mpeg_decode_motion(s, s->mpeg_f_code[0][0], 0);
804 mpeg_decode_motion(s, s->mpeg_f_code[0][1], 0);
808 memset(s->last_mv, 0, sizeof(s->last_mv)); /* reset mv prediction */
813 /* special case of implicit zero motion vector */
814 if (s->pict_type == P_TYPE && !(mb_type & MB_FOR)) {
815 s->mv_dir = MV_DIR_FORWARD;
816 s->mv_type = MV_TYPE_16X16;
817 s->last_mv[0][0][0] = 0;
818 s->last_mv[0][0][1] = 0;
819 s->last_mv[0][1][0] = 0;
820 s->last_mv[0][1][1] = 0;
823 } else if (mb_type & (MB_FOR | MB_BACK)) {
827 if (mb_type & (MB_FOR >> i)) {
828 s->mv_dir |= (MV_DIR_FORWARD >> i);
829 dprintf("motion_type=%d\n", motion_type);
830 switch(motion_type) {
831 case MT_FRAME: /* or MT_16X8 */
832 if (s->picture_structure == PICT_FRAME) {
834 s->mv_type = MV_TYPE_16X16;
836 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
837 s->last_mv[i][0][k]);
838 s->last_mv[i][0][k] = val;
839 s->last_mv[i][1][k] = val;
840 /* full_pel: only for mpeg1 */
843 s->mv[i][0][k] = val;
844 dprintf("mv%d: %d\n", k, val);
848 s->mv_type = MV_TYPE_16X8;
850 s->field_select[i][j] = get_bits1(&s->gb);
852 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
853 s->last_mv[i][j][k]);
854 s->last_mv[i][j][k] = val;
855 s->mv[i][j][k] = val;
861 if (s->picture_structure == PICT_FRAME) {
862 s->mv_type = MV_TYPE_FIELD;
864 s->field_select[i][j] = get_bits1(&s->gb);
865 val = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
866 s->last_mv[i][j][0]);
867 s->last_mv[i][j][0] = val;
868 s->mv[i][j][0] = val;
869 dprintf("fmx=%d\n", val);
870 val = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
871 s->last_mv[i][j][1] >> 1);
872 s->last_mv[i][j][1] = val << 1;
873 s->mv[i][j][1] = val;
874 dprintf("fmy=%d\n", val);
877 s->mv_type = MV_TYPE_16X16;
878 s->field_select[i][0] = get_bits1(&s->gb);
880 val = mpeg_decode_motion(s, s->mpeg_f_code[i][k],
881 s->last_mv[i][0][k]);
882 s->last_mv[i][0][k] = val;
883 s->last_mv[i][1][k] = val;
884 s->mv[i][0][k] = val;
890 int dmx, dmy, mx, my, m;
892 mx = mpeg_decode_motion(s, s->mpeg_f_code[i][0],
893 s->last_mv[i][0][0]);
894 s->last_mv[i][0][0] = mx;
895 s->last_mv[i][1][0] = mx;
897 my = mpeg_decode_motion(s, s->mpeg_f_code[i][1],
898 s->last_mv[i][0][1] >> 1);
900 s->mv_type = MV_TYPE_DMV;
901 /* XXX: totally broken */
902 if (s->picture_structure == PICT_FRAME) {
903 s->last_mv[i][0][1] = my << 1;
904 s->last_mv[i][1][1] = my << 1;
906 m = s->top_field_first ? 1 : 3;
907 /* top -> top pred */
909 s->mv[i][0][1] = my << 1;
910 s->mv[i][1][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
911 s->mv[i][1][1] = ((my * m + (my > 0)) >> 1) + dmy - 1;
914 s->mv[i][2][1] = my << 1;
915 s->mv[i][3][0] = ((mx * m + (mx > 0)) >> 1) + dmx;
916 s->mv[i][3][1] = ((my * m + (my > 0)) >> 1) + dmy + 1;
918 s->last_mv[i][0][1] = my;
919 s->last_mv[i][1][1] = my;
922 s->mv[i][1][0] = ((mx + (mx > 0)) >> 1) + dmx;
923 s->mv[i][1][1] = ((my + (my > 0)) >> 1) + dmy - 1
924 /* + 2 * cur_field */;
933 if ((mb_type & MB_INTRA) && s->concealment_motion_vectors) {
934 skip_bits1(&s->gb); /* marker */
937 if (mb_type & MB_PAT) {
938 cbp = get_vlc2(&s->gb, mb_pat_vlc.table, MB_PAT_VLC_BITS, 1);
940 fprintf(stderr, "invalid cbp at %d %d\n", s->mb_x, s->mb_y);
945 dprintf("cbp=%x\n", cbp);
950 if (cbp & (1 << (5 - i))) {
951 if (mpeg2_decode_block_intra(s, block[i], i) < 0)
954 s->block_last_index[i] = -1;
959 if (cbp & (1 << (5 - i))) {
960 if (mpeg2_decode_block_non_intra(s, block[i], i) < 0)
963 s->block_last_index[i] = -1;
969 if (cbp & (1 << (5 - i))) {
970 if (mpeg1_decode_block(s, block[i], i) < 0)
973 s->block_last_index[i] = -1;
980 /* as h263, but only 17 codes */
981 static int mpeg_decode_motion(MpegEncContext *s, int fcode, int pred)
983 int code, sign, val, m, l, shift;
985 code = get_vlc2(&s->gb, mv_vlc.table, MV_VLC_BITS, 2);
992 sign = get_bits1(&s->gb);
994 val = (code - 1) << shift;
996 val |= get_bits(&s->gb, shift);
1002 /* modulo decoding */
1003 l = (1 << shift) * 16;
1007 } else if (val >= l) {
1013 static inline int decode_dc(MpegEncContext *s, int component)
1017 if (component == 0) {
1018 code = get_vlc2(&s->gb, dc_lum_vlc.table, DC_VLC_BITS, 2);
1020 code = get_vlc2(&s->gb, dc_chroma_vlc.table, DC_VLC_BITS, 2);
1023 fprintf(stderr, "invalid dc code at %d %d\n", s->mb_x, s->mb_y);
1029 diff = get_bits(&s->gb, code);
1030 if ((diff & (1 << (code - 1))) == 0)
1031 diff = (-1 << code) | (diff + 1);
1036 static int mpeg1_decode_block(MpegEncContext *s,
1040 int level, dc, diff, i, j, run;
1041 int code, component;
1042 RLTable *rl = &rl_mpeg1;
1046 component = (n <= 3 ? 0 : n - 4 + 1);
1047 diff = decode_dc(s, component);
1050 dc = s->last_dc[component];
1052 s->last_dc[component] = dc;
1054 dprintf("dc=%d diff=%d\n", dc, diff);
1058 OPEN_READER(re, &s->gb);
1060 /* special case for the first coef. no need to add a second vlc table */
1061 UPDATE_CACHE(re, &s->gb);
1062 v= SHOW_UBITS(re, &s->gb, 2);
1065 level = 1 - ((v & 1) << 1);
1066 SKIP_BITS(re, &s->gb, 2);
1067 CLOSE_READER(re, &s->gb);
1070 CLOSE_READER(re, &s->gb);
1073 /* now quantify & encode AC coefs */
1075 code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2);
1081 } else if (code == 111) {
1083 run = get_bits(&s->gb, 6);
1084 level = get_bits(&s->gb, 8);
1085 level= (level + ((-1)<<7)) ^ ((-1)<<7); //sign extension
1086 if (level == -128) {
1087 level = get_bits(&s->gb, 8) - 256;
1088 } else if (level == 0) {
1089 level = get_bits(&s->gb, 8);
1092 run = rl->table_run[code];
1093 level = rl->table_level[code];
1094 if (get_bits1(&s->gb))
1101 dprintf("%d: run=%d level=%d\n", n, run, level);
1102 j = zigzag_direct[i];
1106 s->block_last_index[n] = i-1;
1110 /* Also does unquantization here, since I will never support mpeg2
1112 static int mpeg2_decode_block_non_intra(MpegEncContext *s,
1116 int level, i, j, run;
1118 RLTable *rl = &rl_mpeg1;
1119 const UINT8 *scan_table;
1120 const UINT16 *matrix;
1123 if (s->alternate_scan)
1124 scan_table = ff_alternate_vertical_scan;
1126 scan_table = zigzag_direct;
1131 OPEN_READER(re, &s->gb);
1134 matrix = s->inter_matrix;
1136 matrix = s->chroma_inter_matrix;
1138 /* special case for the first coef. no need to add a second vlc table */
1139 UPDATE_CACHE(re, &s->gb);
1140 v= SHOW_UBITS(re, &s->gb, 2);
1143 level = 1 - ((v & 1) << 1);
1144 SKIP_BITS(re, &s->gb, 2);
1145 CLOSE_READER(re, &s->gb);
1148 CLOSE_READER(re, &s->gb);
1151 /* now quantify & encode AC coefs */
1153 code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2);
1155 fprintf(stderr, "invalid ac code at %d %d\n", s->mb_x, s->mb_y);
1160 } else if (code == 111) {
1162 run = get_bits(&s->gb, 6);
1163 level = get_bits(&s->gb, 12);
1164 level= (level + ((-1)<<11)) ^ ((-1)<<11); //sign extension
1166 run = rl->table_run[code];
1167 level = rl->table_level[code];
1168 if (get_bits1(&s->gb))
1173 fprintf(stderr, "run too long at %d %d\n", s->mb_x, s->mb_y);
1178 dprintf("%d: run=%d level=%d\n", n, run, level);
1181 level = ((level * 2 + 1) * s->qscale * matrix[j]) >> 5;
1183 level = ((-level * 2 + 1) * s->qscale * matrix[j]) >> 5;
1186 /* XXX: is it really necessary to saturate since the encoder
1187 knows whats going on ? */
1192 block[63] ^= (mismatch & 1);
1193 s->block_last_index[n] = i;
1197 static int mpeg2_decode_block_intra(MpegEncContext *s,
1201 int level, dc, diff, i, j, run;
1202 int code, component;
1204 const UINT8 *scan_table;
1205 const UINT16 *matrix;
1208 if (s->alternate_scan)
1209 scan_table = ff_alternate_vertical_scan;
1211 scan_table = zigzag_direct;
1214 component = (n <= 3 ? 0 : n - 4 + 1);
1215 diff = decode_dc(s, component);
1218 dc = s->last_dc[component];
1220 s->last_dc[component] = dc;
1221 block[0] = dc << (3 - s->intra_dc_precision);
1222 dprintf("dc=%d\n", block[0]);
1223 mismatch = block[0] ^ 1;
1225 if (s->intra_vlc_format)
1230 matrix = s->intra_matrix;
1232 matrix = s->chroma_intra_matrix;
1234 /* now quantify & encode AC coefs */
1236 code = get_vlc2(&s->gb, rl->vlc.table, TEX_VLC_BITS, 2);
1238 fprintf(stderr, "invalid ac code at %d %d\n", s->mb_x, s->mb_y);
1243 } else if (code == 111) {
1245 run = get_bits(&s->gb, 6);
1246 level = get_bits(&s->gb, 12);
1247 level= (level + ((-1)<<11)) ^ ((-1)<<11); //sign extension
1249 run = rl->table_run[code];
1250 level = rl->table_level[code];
1251 if (get_bits1(&s->gb))
1256 fprintf(stderr, "run too long at %d %d\n", s->mb_x, s->mb_y);
1260 dprintf("%d: run=%d level=%d\n", n, run, level);
1261 level = (level * s->qscale * matrix[j]) / 16;
1262 /* XXX: is it really necessary to saturate since the encoder
1263 knows whats going on ? */
1268 block[63] ^= (mismatch & 1);
1269 s->block_last_index[n] = i;
1273 /* compressed picture size */
1274 #define PICTURE_BUFFER_SIZE 100000
1276 typedef struct Mpeg1Context {
1277 MpegEncContext mpeg_enc_ctx;
1278 UINT32 header_state;
1279 int start_code; /* current start code */
1280 UINT8 buffer[PICTURE_BUFFER_SIZE];
1283 int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
1284 int repeat_field; /* true if we must repeat the field */
1287 static int mpeg_decode_init(AVCodecContext *avctx)
1289 Mpeg1Context *s = avctx->priv_data;
1291 s->mpeg_enc_ctx.flags= avctx->flags;
1292 common_init(&s->mpeg_enc_ctx);
1293 init_vlcs(&s->mpeg_enc_ctx);
1295 s->header_state = 0xff;
1296 s->mpeg_enc_ctx_allocated = 0;
1297 s->buffer_size = PICTURE_BUFFER_SIZE;
1299 s->buf_ptr = s->buffer;
1300 s->mpeg_enc_ctx.picture_number = 0;
1301 s->repeat_field = 0;
1302 s->mpeg_enc_ctx.codec_id= avctx->codec->id;
1303 avctx->mbskip_table= s->mpeg_enc_ctx.mbskip_table;
1307 /* return the 8 bit start code value and update the search
1308 state. Return -1 if no start code found */
1309 static int find_start_code(UINT8 **pbuf_ptr, UINT8 *buf_end,
1310 UINT32 *header_state)
1313 unsigned int state, v;
1316 state = *header_state;
1317 buf_ptr = *pbuf_ptr;
1318 while (buf_ptr < buf_end) {
1320 if (state == 0x000001) {
1321 state = ((state << 8) | v) & 0xffffff;
1325 state = ((state << 8) | v) & 0xffffff;
1329 *pbuf_ptr = buf_ptr;
1330 *header_state = state;
1334 static int mpeg1_decode_picture(AVCodecContext *avctx,
1335 UINT8 *buf, int buf_size)
1337 Mpeg1Context *s1 = avctx->priv_data;
1338 MpegEncContext *s = &s1->mpeg_enc_ctx;
1341 init_get_bits(&s->gb, buf, buf_size);
1343 ref = get_bits(&s->gb, 10); /* temporal ref */
1344 s->pict_type = get_bits(&s->gb, 3);
1345 dprintf("pict_type=%d number=%d\n", s->pict_type, s->picture_number);
1346 skip_bits(&s->gb, 16);
1347 if (s->pict_type == P_TYPE || s->pict_type == B_TYPE) {
1348 s->full_pel[0] = get_bits1(&s->gb);
1349 f_code = get_bits(&s->gb, 3);
1352 s->mpeg_f_code[0][0] = f_code;
1353 s->mpeg_f_code[0][1] = f_code;
1355 if (s->pict_type == B_TYPE) {
1356 s->full_pel[1] = get_bits1(&s->gb);
1357 f_code = get_bits(&s->gb, 3);
1360 s->mpeg_f_code[1][0] = f_code;
1361 s->mpeg_f_code[1][1] = f_code;
1369 static void mpeg_decode_sequence_extension(MpegEncContext *s)
1371 int horiz_size_ext, vert_size_ext;
1372 int bit_rate_ext, vbv_buf_ext, low_delay;
1373 int frame_rate_ext_n, frame_rate_ext_d;
1375 skip_bits(&s->gb, 8); /* profil and level */
1376 s->progressive_sequence = get_bits1(&s->gb); /* progressive_sequence */
1377 skip_bits(&s->gb, 2); /* chroma_format */
1378 horiz_size_ext = get_bits(&s->gb, 2);
1379 vert_size_ext = get_bits(&s->gb, 2);
1380 s->width |= (horiz_size_ext << 12);
1381 s->height |= (vert_size_ext << 12);
1382 bit_rate_ext = get_bits(&s->gb, 12); /* XXX: handle it */
1383 s->bit_rate = ((s->bit_rate / 400) | (bit_rate_ext << 12)) * 400;
1384 skip_bits1(&s->gb); /* marker */
1385 vbv_buf_ext = get_bits(&s->gb, 8);
1386 low_delay = get_bits1(&s->gb);
1387 frame_rate_ext_n = get_bits(&s->gb, 2);
1388 frame_rate_ext_d = get_bits(&s->gb, 5);
1389 if (frame_rate_ext_d >= 1)
1390 s->frame_rate = (s->frame_rate * frame_rate_ext_n) / frame_rate_ext_d;
1391 dprintf("sequence extension\n");
1393 s->avctx->sub_id = 2; /* indicates mpeg2 found */
1396 static void mpeg_decode_quant_matrix_extension(MpegEncContext *s)
1400 dprintf("matrix extension\n");
1402 if (get_bits1(&s->gb)) {
1404 v = get_bits(&s->gb, 8);
1405 j = zigzag_direct[i];
1406 s->intra_matrix[j] = v;
1407 s->chroma_intra_matrix[j] = v;
1410 if (get_bits1(&s->gb)) {
1412 v = get_bits(&s->gb, 8);
1413 j = zigzag_direct[i];
1414 s->inter_matrix[j] = v;
1415 s->chroma_inter_matrix[j] = v;
1418 if (get_bits1(&s->gb)) {
1420 v = get_bits(&s->gb, 8);
1421 j = zigzag_direct[i];
1422 s->chroma_intra_matrix[j] = v;
1425 if (get_bits1(&s->gb)) {
1427 v = get_bits(&s->gb, 8);
1428 j = zigzag_direct[i];
1429 s->chroma_inter_matrix[j] = v;
1434 static void mpeg_decode_picture_coding_extension(MpegEncContext *s)
1436 s->full_pel[0] = s->full_pel[1] = 0;
1437 s->mpeg_f_code[0][0] = get_bits(&s->gb, 4);
1438 s->mpeg_f_code[0][1] = get_bits(&s->gb, 4);
1439 s->mpeg_f_code[1][0] = get_bits(&s->gb, 4);
1440 s->mpeg_f_code[1][1] = get_bits(&s->gb, 4);
1441 s->intra_dc_precision = get_bits(&s->gb, 2);
1442 s->picture_structure = get_bits(&s->gb, 2);
1443 s->top_field_first = get_bits1(&s->gb);
1444 s->frame_pred_frame_dct = get_bits1(&s->gb);
1445 s->concealment_motion_vectors = get_bits1(&s->gb);
1446 s->q_scale_type = get_bits1(&s->gb);
1447 s->intra_vlc_format = get_bits1(&s->gb);
1448 s->alternate_scan = get_bits1(&s->gb);
1449 s->repeat_first_field = get_bits1(&s->gb);
1450 s->chroma_420_type = get_bits1(&s->gb);
1451 s->progressive_frame = get_bits1(&s->gb);
1452 /* composite display not parsed */
1453 dprintf("intra_dc_precision=%d\n", s->intra_dc_precision);
1454 dprintf("picture_structure=%d\n", s->picture_structure);
1455 dprintf("top field first=%d\n", s->top_field_first);
1456 dprintf("repeat first field=%d\n", s->repeat_first_field);
1457 dprintf("conceal=%d\n", s->concealment_motion_vectors);
1458 dprintf("intra_vlc_format=%d\n", s->intra_vlc_format);
1459 dprintf("alternate_scan=%d\n", s->alternate_scan);
1460 dprintf("frame_pred_frame_dct=%d\n", s->frame_pred_frame_dct);
1461 dprintf("progressive_frame=%d\n", s->progressive_frame);
1464 static void mpeg_decode_extension(AVCodecContext *avctx,
1465 UINT8 *buf, int buf_size)
1467 Mpeg1Context *s1 = avctx->priv_data;
1468 MpegEncContext *s = &s1->mpeg_enc_ctx;
1471 init_get_bits(&s->gb, buf, buf_size);
1473 ext_type = get_bits(&s->gb, 4);
1477 mpeg_decode_sequence_extension(s);
1480 /* quant matrix extension */
1481 mpeg_decode_quant_matrix_extension(s);
1484 /* picture extension */
1485 mpeg_decode_picture_coding_extension(s);
1490 /* return 1 if end of frame */
1491 static int mpeg_decode_slice(AVCodecContext *avctx,
1494 UINT8 *buf, int buf_size)
1496 Mpeg1Context *s1 = avctx->priv_data;
1497 MpegEncContext *s = &s1->mpeg_enc_ctx;
1500 start_code = (start_code - 1) & 0xff;
1501 if (start_code >= s->mb_height){
1502 fprintf(stderr, "slice below image (%d >= %d)\n", start_code, s->mb_height);
1505 s->last_dc[0] = 1 << (7 + s->intra_dc_precision);
1506 s->last_dc[1] = s->last_dc[0];
1507 s->last_dc[2] = s->last_dc[0];
1508 memset(s->last_mv, 0, sizeof(s->last_mv));
1510 s->mb_y = start_code;
1512 /* start frame decoding */
1513 if (s->first_slice) {
1515 MPV_frame_start(s, avctx);
1518 init_get_bits(&s->gb, buf, buf_size);
1520 s->qscale = get_qscale(s);
1521 /* extra slice info */
1522 while (get_bits1(&s->gb) != 0) {
1523 skip_bits(&s->gb, 8);
1527 clear_blocks(s->block[0]);
1529 ret = mpeg_decode_mb(s, s->block);
1530 dprintf("ret=%d\n", ret);
1537 PRINT_QP("%s", "\n");
1538 PRINT_QP("%2d", s->qscale);
1540 MPV_decode_mb(s, s->block);
1544 /* end of slice reached */
1545 if (s->mb_x == (s->mb_width - 1) &&
1546 s->mb_y == (s->mb_height - 1)) {
1552 /* XXX: incorrect reported qscale for mpeg2 */
1553 if (s->pict_type == B_TYPE) {
1554 picture = s->current_picture;
1555 avctx->quality = s->qscale;
1557 /* latency of 1 frame for I and P frames */
1558 /* XXX: use another variable than picture_number */
1559 if (s->picture_number == 0) {
1562 picture = s->last_picture;
1563 avctx->quality = s->last_qscale;
1565 s->last_qscale = s->qscale;
1566 s->picture_number++;
1569 pict->data[0] = picture[0];
1570 pict->data[1] = picture[1];
1571 pict->data[2] = picture[2];
1572 pict->linesize[0] = s->linesize;
1573 pict->linesize[1] = s->uvlinesize;
1574 pict->linesize[2] = s->uvlinesize;
1584 static int mpeg1_decode_sequence(AVCodecContext *avctx,
1585 UINT8 *buf, int buf_size)
1587 Mpeg1Context *s1 = avctx->priv_data;
1588 MpegEncContext *s = &s1->mpeg_enc_ctx;
1589 int width, height, i, v, j;
1591 init_get_bits(&s->gb, buf, buf_size);
1593 width = get_bits(&s->gb, 12);
1594 height = get_bits(&s->gb, 12);
1595 skip_bits(&s->gb, 4);
1596 s->frame_rate_index = get_bits(&s->gb, 4);
1597 if (s->frame_rate_index == 0)
1599 s->bit_rate = get_bits(&s->gb, 18) * 400;
1600 if (get_bits1(&s->gb) == 0) /* marker */
1602 if (width <= 0 || height <= 0 ||
1603 (width % 2) != 0 || (height % 2) != 0)
1605 if (width != s->width ||
1606 height != s->height) {
1607 /* start new mpeg1 context decoding */
1608 s->out_format = FMT_MPEG1;
1609 if (s1->mpeg_enc_ctx_allocated) {
1614 avctx->has_b_frames= s->has_b_frames = 1;
1616 avctx->width = width;
1617 avctx->height = height;
1618 if (s->frame_rate_index >= 9) {
1619 /* at least give a valid frame rate (some old mpeg1 have this) */
1620 avctx->frame_rate = 25 * FRAME_RATE_BASE;
1622 avctx->frame_rate = frame_rate_tab[s->frame_rate_index];
1624 s->frame_rate = avctx->frame_rate;
1625 avctx->bit_rate = s->bit_rate;
1627 if (MPV_common_init(s) < 0)
1629 s1->mpeg_enc_ctx_allocated = 1;
1632 skip_bits(&s->gb, 10); /* vbv_buffer_size */
1633 skip_bits(&s->gb, 1);
1636 if (get_bits1(&s->gb)) {
1638 v = get_bits(&s->gb, 8);
1639 j = zigzag_direct[i];
1640 s->intra_matrix[j] = v;
1641 s->chroma_intra_matrix[j] = v;
1644 dprintf("intra matrix present\n");
1646 dprintf(" %d", s->intra_matrix[zigzag_direct[i]]);
1651 v = ff_mpeg1_default_intra_matrix[i];
1652 s->intra_matrix[i] = v;
1653 s->chroma_intra_matrix[i] = v;
1656 if (get_bits1(&s->gb)) {
1658 v = get_bits(&s->gb, 8);
1659 j = zigzag_direct[i];
1660 s->inter_matrix[j] = v;
1661 s->chroma_inter_matrix[j] = v;
1664 dprintf("non intra matrix present\n");
1666 dprintf(" %d", s->inter_matrix[zigzag_direct[i]]);
1671 v = ff_mpeg1_default_non_intra_matrix[i];
1672 s->inter_matrix[i] = v;
1673 s->chroma_inter_matrix[i] = v;
1677 /* we set mpeg2 parameters so that it emulates mpeg1 */
1678 s->progressive_sequence = 1;
1679 s->progressive_frame = 1;
1680 s->picture_structure = PICT_FRAME;
1681 s->frame_pred_frame_dct = 1;
1683 avctx->sub_id = 1; /* indicates mpeg1 */
1687 /* handle buffering and image synchronisation */
1688 static int mpeg_decode_frame(AVCodecContext *avctx,
1689 void *data, int *data_size,
1690 UINT8 *buf, int buf_size)
1692 Mpeg1Context *s = avctx->priv_data;
1693 UINT8 *buf_end, *buf_ptr, *buf_start;
1694 int len, start_code_found, ret, code, start_code, input_size;
1695 AVPicture *picture = data;
1696 MpegEncContext *s2 = &s->mpeg_enc_ctx;
1698 dprintf("fill_buffer\n");
1702 /* special case for last picture */
1703 if (buf_size == 0) {
1704 if (s2->picture_number > 0) {
1705 picture->data[0] = s2->next_picture[0];
1706 picture->data[1] = s2->next_picture[1];
1707 picture->data[2] = s2->next_picture[2];
1708 picture->linesize[0] = s2->linesize;
1709 picture->linesize[1] = s2->uvlinesize;
1710 picture->linesize[2] = s2->uvlinesize;
1711 *data_size = sizeof(AVPicture);
1717 buf_end = buf + buf_size;
1720 if (s->repeat_field % 2 == 1) {
1722 //fprintf(stderr,"\nRepeating last frame: %d -> %d! pict: %d %d", avctx->frame_number-1, avctx->frame_number,
1723 // s2->picture_number, s->repeat_field);
1724 if (avctx->flags & CODEC_FLAG_REPEAT_FIELD) {
1725 *data_size = sizeof(AVPicture);
1730 while (buf_ptr < buf_end) {
1731 buf_start = buf_ptr;
1732 /* find start next code */
1733 code = find_start_code(&buf_ptr, buf_end, &s->header_state);
1735 start_code_found = 1;
1737 start_code_found = 0;
1739 /* copy to buffer */
1740 len = buf_ptr - buf_start;
1741 if (len + (s->buf_ptr - s->buffer) > s->buffer_size) {
1742 /* data too big : flush */
1743 s->buf_ptr = s->buffer;
1744 if (start_code_found)
1745 s->start_code = code;
1747 memcpy(s->buf_ptr, buf_start, len);
1749 if( (s2->flags&CODEC_FLAG_NOT_TRUNCATED) && (!start_code_found)
1750 && s->buf_ptr+4<s->buffer+s->buffer_size){
1751 start_code_found= 1;
1753 s->header_state=0xFF;
1760 if (start_code_found) {
1761 /* prepare data for next start code */
1762 input_size = s->buf_ptr - s->buffer;
1763 start_code = s->start_code;
1764 s->buf_ptr = s->buffer;
1765 s->start_code = code;
1766 switch(start_code) {
1767 case SEQ_START_CODE:
1768 mpeg1_decode_sequence(avctx, s->buffer,
1772 case PICTURE_START_CODE:
1773 /* we have a complete image : we try to decompress it */
1774 mpeg1_decode_picture(avctx,
1775 s->buffer, input_size);
1777 case EXT_START_CODE:
1778 mpeg_decode_extension(avctx,
1779 s->buffer, input_size);
1782 if (start_code >= SLICE_MIN_START_CODE &&
1783 start_code <= SLICE_MAX_START_CODE) {
1784 ret = mpeg_decode_slice(avctx, picture,
1785 start_code, s->buffer, input_size);
1787 /* got a picture: exit */
1788 /* first check if we must repeat the frame */
1789 avctx->repeat_pict = 0;
1791 if (s2->progressive_frame && s2->repeat_first_field) {
1792 //fprintf(stderr,"\nRepeat this frame: %d! pict: %d",avctx->frame_number,s2->picture_number);
1793 //s2->repeat_first_field = 0;
1794 //s2->progressive_frame = 0;
1795 if (++s->repeat_field > 2)
1796 s->repeat_field = 0;
1797 avctx->repeat_pict = 1;
1800 if (s2->repeat_first_field) {
1801 if (s2->progressive_sequence) {
1802 if (s2->top_field_first)
1803 avctx->repeat_pict = 4;
1805 avctx->repeat_pict = 2;
1806 } else if (s2->progressive_frame) {
1807 avctx->repeat_pict = 1;
1810 *data_size = sizeof(AVPicture);
1813 printf("Error while decoding slice\n");
1822 return buf_ptr - buf;
1825 static int mpeg_decode_end(AVCodecContext *avctx)
1827 Mpeg1Context *s = avctx->priv_data;
1829 if (s->mpeg_enc_ctx_allocated)
1830 MPV_common_end(&s->mpeg_enc_ctx);
1834 AVCodec mpeg_decoder = {
1837 CODEC_ID_MPEG1VIDEO,
1838 sizeof(Mpeg1Context),