3 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
4 * Copyright (c) 2004 Maarten Daniels
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
30 #include "mpegvideo.h"
34 #define H261_MBA_VLC_BITS 9
35 #define H261_MTYPE_VLC_BITS 6
36 #define H261_MV_VLC_BITS 7
37 #define H261_CBP_VLC_BITS 9
38 #define TCOEFF_VLC_BITS 9
40 #define MBA_STUFFING 33
41 #define MBA_STARTCODE 34
42 #define IS_FIL(a) ((a)&MB_TYPE_H261_FIL)
47 typedef struct H261Context{
57 int gob_start_code_skipped; // 1 if gob start code is already read before gob header is read
60 static uint8_t static_rl_table_store[2][2*MAX_RUN + MAX_LEVEL + 3];
62 void ff_h261_loop_filter(MpegEncContext *s){
63 H261Context * h= (H261Context*)s;
64 const int linesize = s->linesize;
65 const int uvlinesize= s->uvlinesize;
66 uint8_t *dest_y = s->dest[0];
67 uint8_t *dest_cb= s->dest[1];
68 uint8_t *dest_cr= s->dest[2];
70 if(!(IS_FIL (h->mtype)))
73 s->dsp.h261_loop_filter(dest_y , linesize);
74 s->dsp.h261_loop_filter(dest_y + 8, linesize);
75 s->dsp.h261_loop_filter(dest_y + 8 * linesize , linesize);
76 s->dsp.h261_loop_filter(dest_y + 8 * linesize + 8, linesize);
77 s->dsp.h261_loop_filter(dest_cb, uvlinesize);
78 s->dsp.h261_loop_filter(dest_cr, uvlinesize);
81 int ff_h261_get_picture_format(int width, int height){
83 if (width == 176 && height == 144)
86 else if (width == 352 && height == 288)
93 static void h261_encode_block(H261Context * h, DCTELEM * block,
95 static int h261_decode_block(H261Context *h, DCTELEM *block,
98 void ff_h261_encode_picture_header(MpegEncContext * s, int picture_number){
99 H261Context * h = (H261Context *) s;
100 int format, temp_ref;
102 align_put_bits(&s->pb);
104 /* Update the pointer to last GOB */
105 s->ptr_lastgob = pbBufPtr(&s->pb);
107 put_bits(&s->pb, 20, 0x10); /* PSC */
109 temp_ref= s->picture_number * (int64_t)30000 * s->avctx->time_base.num /
110 (1001 * (int64_t)s->avctx->time_base.den); //FIXME maybe this should use a timestamp
111 put_bits(&s->pb, 5, temp_ref & 0x1f); /* TemporalReference */
113 put_bits(&s->pb, 1, 0); /* split screen off */
114 put_bits(&s->pb, 1, 0); /* camera off */
115 put_bits(&s->pb, 1, 0); /* freeze picture release off */
117 format = ff_h261_get_picture_format(s->width, s->height);
119 put_bits(&s->pb, 1, format); /* 0 == QCIF, 1 == CIF */
121 put_bits(&s->pb, 1, 0); /* still image mode */
122 put_bits(&s->pb, 1, 0); /* reserved */
124 put_bits(&s->pb, 1, 0); /* no PEI */
133 * Encodes a group of blocks header.
135 static void h261_encode_gob_header(MpegEncContext * s, int mb_line){
136 H261Context * h = (H261Context *)s;
137 if(ff_h261_get_picture_format(s->width, s->height) == 0){
138 h->gob_number+=2; // QCIF
141 h->gob_number++; // CIF
143 put_bits(&s->pb, 16, 1); /* GBSC */
144 put_bits(&s->pb, 4, h->gob_number); /* GN */
145 put_bits(&s->pb, 5, s->qscale); /* GQUANT */
146 put_bits(&s->pb, 1, 0); /* no GEI */
153 void ff_h261_reorder_mb_index(MpegEncContext* s){
154 int index= s->mb_x + s->mb_y*s->mb_width;
157 h261_encode_gob_header(s,0);
159 /* for CIF the GOB's are fragmented in the middle of a scanline
160 that's why we need to adjust the x and y index of the macroblocks */
161 if(ff_h261_get_picture_format(s->width,s->height) == 1){ // CIF
162 s->mb_x = index % 11 ; index /= 11;
163 s->mb_y = index % 3 ; index /= 3;
164 s->mb_x+= 11*(index % 2); index /= 2;
167 ff_init_block_index(s);
168 ff_update_block_index(s);
172 static void h261_encode_motion(H261Context * h, int val){
173 MpegEncContext * const s = &h->s;
177 put_bits(&s->pb,h261_mv_tab[code][1],h261_mv_tab[code][0]);
185 code = sign ? -val : val;
186 put_bits(&s->pb,h261_mv_tab[code][1],h261_mv_tab[code][0]);
187 put_bits(&s->pb,1,sign);
191 static inline int get_cbp(MpegEncContext * s,
192 DCTELEM block[6][64])
196 for (i = 0; i < 6; i++) {
197 if (s->block_last_index[i] >= 0)
202 void ff_h261_encode_mb(MpegEncContext * s,
203 DCTELEM block[6][64],
204 int motion_x, int motion_y)
206 H261Context * h = (H261Context *)s;
207 int mvd, mv_diff_x, mv_diff_y, i, cbp;
208 cbp = 63; // avoid warning
216 cbp= get_cbp(s, block);
218 /* mvd indicates if this block is motion compensated */
219 mvd = motion_x | motion_y;
221 if((cbp | mvd | s->dquant ) == 0) {
222 /* skip macroblock */
230 /* MB is not skipped, encode MBA */
231 put_bits(&s->pb, h261_mba_bits[(h->current_mba-h->previous_mba)-1], h261_mba_code[(h->current_mba-h->previous_mba)-1]);
233 /* calculate MTYPE */
237 if(mvd || s->loop_filter)
243 assert(h->mtype > 1);
249 put_bits(&s->pb, h261_mtype_bits[h->mtype], h261_mtype_code[h->mtype]);
251 h->mtype = h261_mtype_map[h->mtype];
253 if(IS_QUANT(h->mtype)){
254 ff_set_qscale(s,s->qscale+s->dquant);
255 put_bits(&s->pb, 5, s->qscale);
258 if(IS_16X16(h->mtype)){
259 mv_diff_x = (motion_x >> 1) - h->current_mv_x;
260 mv_diff_y = (motion_y >> 1) - h->current_mv_y;
261 h->current_mv_x = (motion_x >> 1);
262 h->current_mv_y = (motion_y >> 1);
263 h261_encode_motion(h,mv_diff_x);
264 h261_encode_motion(h,mv_diff_y);
267 h->previous_mba = h->current_mba;
269 if(HAS_CBP(h->mtype)){
271 put_bits(&s->pb,h261_cbp_tab[cbp-1][1],h261_cbp_tab[cbp-1][0]);
274 /* encode each block */
275 h261_encode_block(h, block[i], i);
278 if ( ( h->current_mba == 11 ) || ( h->current_mba == 22 ) || ( h->current_mba == 33 ) || ( !IS_16X16 ( h->mtype ) )){
284 void ff_h261_encode_init(MpegEncContext *s){
289 init_rl(&h261_rl_tcoeff, static_rl_table_store);
295 s->c_dc_scale_table= ff_mpeg1_dc_scale_table;
300 * encodes a 8x8 block.
301 * @param block the 8x8 block
302 * @param n block index (0-3 are luma, 4-5 are chroma)
304 static void h261_encode_block(H261Context * h, DCTELEM * block, int n){
305 MpegEncContext * const s = &h->s;
306 int level, run, last, i, j, last_index, last_non_zero, sign, slevel, code;
309 rl = &h261_rl_tcoeff;
313 /* 255 cannot be represented, so we clamp */
318 /* 0 cannot be represented also */
319 else if (level < 1) {
324 put_bits(&s->pb, 8, 0xff);
326 put_bits(&s->pb, 8, level);
328 } else if((block[0]==1 || block[0] == -1) && (s->block_last_index[n] > -1)){
330 put_bits(&s->pb,2,block[0]>0 ? 2 : 3 );
337 last_index = s->block_last_index[n];
338 last_non_zero = i - 1;
339 for (; i <= last_index; i++) {
340 j = s->intra_scantable.permutated[i];
343 run = i - last_non_zero - 1;
344 last = (i == last_index);
351 code = get_rl_index(rl, 0 /*no last in H.261, EOB is used*/, run, level);
352 if(run==0 && level < 16)
354 put_bits(&s->pb, rl->table_vlc[code][1], rl->table_vlc[code][0]);
356 put_bits(&s->pb, 6, run);
358 assert(level <= 127);
359 put_bits(&s->pb, 8, slevel & 0xff);
361 put_bits(&s->pb, 1, sign);
367 put_bits(&s->pb, rl->table_vlc[0][1], rl->table_vlc[0][0]);// END OF BLOCK
371 /***********************************************/
374 static VLC h261_mba_vlc;
375 static VLC h261_mtype_vlc;
376 static VLC h261_mv_vlc;
377 static VLC h261_cbp_vlc;
379 static void h261_decode_init_vlc(H261Context *h){
384 init_vlc(&h261_mba_vlc, H261_MBA_VLC_BITS, 35,
386 h261_mba_code, 1, 1, 1);
387 init_vlc(&h261_mtype_vlc, H261_MTYPE_VLC_BITS, 10,
388 h261_mtype_bits, 1, 1,
389 h261_mtype_code, 1, 1, 1);
390 init_vlc(&h261_mv_vlc, H261_MV_VLC_BITS, 17,
391 &h261_mv_tab[0][1], 2, 1,
392 &h261_mv_tab[0][0], 2, 1, 1);
393 init_vlc(&h261_cbp_vlc, H261_CBP_VLC_BITS, 63,
394 &h261_cbp_tab[0][1], 2, 1,
395 &h261_cbp_tab[0][0], 2, 1, 1);
396 init_rl(&h261_rl_tcoeff, static_rl_table_store);
397 init_vlc_rl(&h261_rl_tcoeff, 1);
401 static int h261_decode_init(AVCodecContext *avctx){
402 H261Context *h= avctx->priv_data;
403 MpegEncContext * const s = &h->s;
406 MPV_decode_defaults(s);
409 s->width = s->avctx->coded_width;
410 s->height = s->avctx->coded_height;
411 s->codec_id = s->avctx->codec->id;
413 s->out_format = FMT_H261;
415 avctx->pix_fmt= PIX_FMT_YUV420P;
417 s->codec_id= avctx->codec->id;
419 h261_decode_init_vlc(h);
421 h->gob_start_code_skipped = 0;
427 * decodes the group of blocks header or slice header.
428 * @return <0 if an error occured
430 static int h261_decode_gob_header(H261Context *h){
432 MpegEncContext * const s = &h->s;
434 if ( !h->gob_start_code_skipped ){
435 /* Check for GOB Start Code */
436 val = show_bits(&s->gb, 15);
441 skip_bits(&s->gb, 16);
444 h->gob_start_code_skipped = 0;
446 h->gob_number = get_bits(&s->gb, 4); /* GN */
447 s->qscale = get_bits(&s->gb, 5); /* GQUANT */
449 /* Check if gob_number is valid */
450 if (s->mb_height==18){ //cif
451 if ((h->gob_number<=0) || (h->gob_number>12))
455 if ((h->gob_number!=1) && (h->gob_number!=3) && (h->gob_number!=5))
460 while (get_bits1(&s->gb) != 0) {
461 skip_bits(&s->gb, 8);
467 // For the first transmitted macroblock in a GOB, MBA is the absolute address. For
468 // subsequent macroblocks, MBA is the difference between the absolute addresses of
469 // the macroblock and the last transmitted macroblock.
477 * decodes the group of blocks / video packet header.
478 * @return <0 if no resync found
480 static int ff_h261_resync(H261Context *h){
481 MpegEncContext * const s = &h->s;
484 if ( h->gob_start_code_skipped ){
485 ret= h261_decode_gob_header(h);
490 if(show_bits(&s->gb, 15)==0){
491 ret= h261_decode_gob_header(h);
495 //ok, its not where its supposed to be ...
496 s->gb= s->last_resync_gb;
497 align_get_bits(&s->gb);
498 left= s->gb.size_in_bits - get_bits_count(&s->gb);
500 for(;left>15+1+4+5; left-=8){
501 if(show_bits(&s->gb, 15)==0){
502 GetBitContext bak= s->gb;
504 ret= h261_decode_gob_header(h);
510 skip_bits(&s->gb, 8);
518 * decodes skipped macroblocks
521 static int h261_decode_mb_skipped(H261Context *h, int mba1, int mba2 )
523 MpegEncContext * const s = &h->s;
528 for(i=mba1; i<mba2; i++){
531 s->mb_x= ((h->gob_number-1) % 2) * 11 + i % 11;
532 s->mb_y= ((h->gob_number-1) / 2) * 3 + i / 11;
533 xy = s->mb_x + s->mb_y * s->mb_stride;
534 ff_init_block_index(s);
535 ff_update_block_index(s);
538 s->block_last_index[j] = -1;
540 s->mv_dir = MV_DIR_FORWARD;
541 s->mv_type = MV_TYPE_16X16;
542 s->current_picture.mb_type[xy]= MB_TYPE_SKIP | MB_TYPE_16x16 | MB_TYPE_L0;
546 h->mtype &= ~MB_TYPE_H261_FIL;
548 MPV_decode_mb(s, s->block);
554 static int decode_mv_component(GetBitContext *gb, int v){
555 int mv_diff = get_vlc2(gb, h261_mv_vlc.table, H261_MV_VLC_BITS, 2);
557 /* check if mv_diff is valid */
561 mv_diff = mvmap[mv_diff];
563 if(mv_diff && !get_bits1(gb))
568 else if(v >= 16) v-= 32;
573 static int h261_decode_mb(H261Context *h){
574 MpegEncContext * const s = &h->s;
580 h->mba_diff = get_vlc2(&s->gb, h261_mba_vlc.table, H261_MBA_VLC_BITS, 2);
582 /* Check for slice end */
583 /* NOTE: GOB can be empty (no MB data) or exist only of MBA_stuffing */
584 if (h->mba_diff == MBA_STARTCODE){ // start code
585 h->gob_start_code_skipped = 1;
589 while( h->mba_diff == MBA_STUFFING ); // stuffing
591 if ( h->mba_diff < 0 ){
592 if ( get_bits_count(&s->gb) + 7 >= s->gb.size_in_bits )
595 av_log(s->avctx, AV_LOG_ERROR, "illegal mba at %d %d\n", s->mb_x, s->mb_y);
600 h->current_mba += h->mba_diff;
602 if ( h->current_mba > MBA_STUFFING )
605 s->mb_x= ((h->gob_number-1) % 2) * 11 + ((h->current_mba-1) % 11);
606 s->mb_y= ((h->gob_number-1) / 2) * 3 + ((h->current_mba-1) / 11);
607 xy = s->mb_x + s->mb_y * s->mb_stride;
608 ff_init_block_index(s);
609 ff_update_block_index(s);
612 h->mtype = get_vlc2(&s->gb, h261_mtype_vlc.table, H261_MTYPE_VLC_BITS, 2);
613 h->mtype = h261_mtype_map[h->mtype];
616 if ( IS_QUANT ( h->mtype ) ){
617 ff_set_qscale(s, get_bits(&s->gb, 5));
620 s->mb_intra = IS_INTRA4x4(h->mtype);
623 if ( IS_16X16 ( h->mtype ) ){
624 // Motion vector data is included for all MC macroblocks. MVD is obtained from the macroblock vector by subtracting the
625 // vector of the preceding macroblock. For this calculation the vector of the preceding macroblock is regarded as zero in the
626 // following three situations:
627 // 1) evaluating MVD for macroblocks 1, 12 and 23;
628 // 2) evaluating MVD for macroblocks in which MBA does not represent a difference of 1;
629 // 3) MTYPE of the previous macroblock was not MC.
630 if ( ( h->current_mba == 1 ) || ( h->current_mba == 12 ) || ( h->current_mba == 23 ) ||
637 h->current_mv_x= decode_mv_component(&s->gb, h->current_mv_x);
638 h->current_mv_y= decode_mv_component(&s->gb, h->current_mv_y);
645 if ( HAS_CBP( h->mtype ) ){
646 cbp = get_vlc2(&s->gb, h261_cbp_vlc.table, H261_CBP_VLC_BITS, 2) + 1;
650 s->current_picture.mb_type[xy]= MB_TYPE_INTRA;
655 s->mv_dir = MV_DIR_FORWARD;
656 s->mv_type = MV_TYPE_16X16;
657 s->current_picture.mb_type[xy]= MB_TYPE_16x16 | MB_TYPE_L0;
658 s->mv[0][0][0] = h->current_mv_x * 2;//gets divided by 2 in motion compensation
659 s->mv[0][0][1] = h->current_mv_y * 2;
662 /* decode each block */
663 if(s->mb_intra || HAS_CBP(h->mtype)){
664 s->dsp.clear_blocks(s->block[0]);
665 for (i = 0; i < 6; i++) {
666 if (h261_decode_block(h, s->block[i], i, cbp&32) < 0){
672 for (i = 0; i < 6; i++)
673 s->block_last_index[i]= -1;
676 MPV_decode_mb(s, s->block);
682 * decodes a macroblock
683 * @return <0 if an error occured
685 static int h261_decode_block(H261Context * h, DCTELEM * block,
688 MpegEncContext * const s = &h->s;
689 int code, level, i, j, run;
690 RLTable *rl = &h261_rl_tcoeff;
691 const uint8_t *scan_table;
693 // For the variable length encoding there are two code tables, one being used for
694 // the first transmitted LEVEL in INTER, INTER+MC and INTER+MC+FIL blocks, the second
695 // for all other LEVELs except the first one in INTRA blocks which is fixed length
696 // coded with 8 bits.
697 // NOTE: the two code tables only differ in one VLC so we handle that manually.
698 scan_table = s->intra_scantable.permutated;
701 level = get_bits(&s->gb, 8);
702 // 0 (00000000b) and -128 (10000000b) are FORBIDDEN
703 if((level&0x7F) == 0){
704 av_log(s->avctx, AV_LOG_ERROR, "illegal dc %d at %d %d\n", level, s->mb_x, s->mb_y);
707 // The code 1000 0000 is not used, the reconstruction level of 1024 being coded as 1111 1111.
714 // EOB Not possible for first level when cbp is available (that's why the table is different)
717 int check = show_bits(&s->gb, 2);
720 skip_bits(&s->gb, 2);
721 block[0] = ( check & 0x1 ) ? -1 : 1;
728 s->block_last_index[n] = i - 1;
732 code = get_vlc2(&s->gb, rl->vlc.table, TCOEFF_VLC_BITS, 2);
734 av_log(s->avctx, AV_LOG_ERROR, "illegal ac vlc code at %dx%d\n", s->mb_x, s->mb_y);
739 // The remaining combinations of (run, level) are encoded with a 20-bit word consisting of 6 bits escape, 6 bits run and 8 bits level.
740 run = get_bits(&s->gb, 6);
741 level = get_sbits(&s->gb, 8);
745 run = rl->table_run[code];
746 level = rl->table_level[code];
747 if (get_bits1(&s->gb))
752 av_log(s->avctx, AV_LOG_ERROR, "run overflow at %dx%d\n", s->mb_x, s->mb_y);
759 s->block_last_index[n] = i-1;
764 * decodes the H261 picture header.
765 * @return <0 if no startcode found
767 static int h261_decode_picture_header(H261Context *h){
768 MpegEncContext * const s = &h->s;
770 uint32_t startcode= 0;
772 for(i= s->gb.size_in_bits - get_bits_count(&s->gb); i>24; i-=1){
773 startcode = ((startcode << 1) | get_bits(&s->gb, 1)) & 0x000FFFFF;
775 if(startcode == 0x10)
779 if (startcode != 0x10){
780 av_log(s->avctx, AV_LOG_ERROR, "Bad picture start code\n");
784 /* temporal reference */
785 i= get_bits(&s->gb, 5); /* picture timestamp */
786 if(i < (s->picture_number&31))
788 s->picture_number = (s->picture_number&~31) + i;
790 s->avctx->time_base= (AVRational){1001, 30000};
791 s->current_picture.pts= s->picture_number;
794 /* PTYPE starts here */
795 skip_bits1(&s->gb); /* split screen off */
796 skip_bits1(&s->gb); /* camera off */
797 skip_bits1(&s->gb); /* freeze picture release off */
799 format = get_bits1(&s->gb);
801 //only 2 formats possible
802 if (format == 0){//QCIF
814 s->mb_num = s->mb_width * s->mb_height;
816 skip_bits1(&s->gb); /* still image mode off */
817 skip_bits1(&s->gb); /* Reserved */
820 while (get_bits1(&s->gb) != 0){
821 skip_bits(&s->gb, 8);
824 // h261 has no I-FRAMES, but if we pass I_TYPE for the first frame, the codec crashes if it does
825 // not contain all I-blocks (e.g. when a packet is lost)
826 s->pict_type = P_TYPE;
832 static int h261_decode_gob(H261Context *h){
833 MpegEncContext * const s = &h->s;
835 ff_set_qscale(s, s->qscale);
838 while(h->current_mba <= MBA_STUFFING)
842 ret= h261_decode_mb(h);
845 h261_decode_mb_skipped(h, h->current_mba, 33);
848 av_log(s->avctx, AV_LOG_ERROR, "Error at MB: %d\n", s->mb_x + s->mb_y*s->mb_stride);
852 h261_decode_mb_skipped(h, h->current_mba-h->mba_diff, h->current_mba-1);
859 * returns the number of bytes consumed for building the current frame
861 static int get_consumed_bytes(MpegEncContext *s, int buf_size){
862 int pos= get_bits_count(&s->gb)>>3;
863 if(pos==0) pos=1; //avoid infinite loops (i doubt thats needed but ...)
864 if(pos+10>buf_size) pos=buf_size; // oops ;)
869 static int h261_decode_frame(AVCodecContext *avctx,
870 void *data, int *data_size,
871 uint8_t *buf, int buf_size)
873 H261Context *h= avctx->priv_data;
874 MpegEncContext *s = &h->s;
876 AVFrame *pict = data;
879 av_log(avctx, AV_LOG_DEBUG, "*****frame %d size=%d\n", avctx->frame_number, buf_size);
880 av_log(avctx, AV_LOG_DEBUG, "bytes=%x %x %x %x\n", buf[0], buf[1], buf[2], buf[3]);
882 s->flags= avctx->flags;
883 s->flags2= avctx->flags2;
885 h->gob_start_code_skipped=0;
889 init_get_bits(&s->gb, buf, buf_size*8);
891 if(!s->context_initialized){
892 if (MPV_common_init(s) < 0) //we need the idct permutaton for reading a custom matrix
896 //we need to set current_picture_ptr before reading the header, otherwise we cant store anyting im there
897 if(s->current_picture_ptr==NULL || s->current_picture_ptr->data[0]){
898 int i= ff_find_unused_picture(s, 0);
899 s->current_picture_ptr= &s->picture[i];
902 ret = h261_decode_picture_header(h);
904 /* skip if the header was thrashed */
906 av_log(s->avctx, AV_LOG_ERROR, "header damaged\n");
910 if (s->width != avctx->coded_width || s->height != avctx->coded_height){
911 ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
912 s->parse_context.buffer=0;
914 s->parse_context= pc;
916 if (!s->context_initialized) {
917 avcodec_set_dimensions(avctx, s->width, s->height);
923 s->current_picture.pict_type= s->pict_type;
924 s->current_picture.key_frame= s->pict_type == I_TYPE;
926 /* skip everything if we are in a hurry>=5 */
927 if(avctx->hurry_up>=5) return get_consumed_bytes(s, buf_size);
928 if( (avctx->skip_frame >= AVDISCARD_NONREF && s->pict_type==B_TYPE)
929 ||(avctx->skip_frame >= AVDISCARD_NONKEY && s->pict_type!=I_TYPE)
930 || avctx->skip_frame >= AVDISCARD_ALL)
931 return get_consumed_bytes(s, buf_size);
933 if(MPV_frame_start(s, avctx) < 0)
936 ff_er_frame_start(s);
938 /* decode each macroblock */
942 while(h->gob_number < (s->mb_height==18 ? 12 : 5)){
943 if(ff_h261_resync(h)<0)
949 assert(s->current_picture.pict_type == s->current_picture_ptr->pict_type);
950 assert(s->current_picture.pict_type == s->pict_type);
951 *pict= *(AVFrame*)s->current_picture_ptr;
952 ff_print_debug_info(s, pict);
954 *data_size = sizeof(AVFrame);
956 return get_consumed_bytes(s, buf_size);
959 static int h261_decode_end(AVCodecContext *avctx)
961 H261Context *h= avctx->priv_data;
962 MpegEncContext *s = &h->s;
968 #ifdef CONFIG_ENCODERS
969 AVCodec h261_encoder = {
977 .pix_fmts= (enum PixelFormat[]){PIX_FMT_YUV420P, -1},
981 AVCodec h261_decoder = {