2 * Chinese AVS video (AVS1-P2, JiZhun profile) decoder.
3 * Copyright (c) 2006 Stefan Gehrer <stefan.gehrer@gmx.de>
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * Chinese AVS video (AVS1-P2, JiZhun profile) decoder
25 * @author Stefan Gehrer <stefan.gehrer@gmx.de>
33 static const uint8_t mv_scan[4] = {
38 static const uint8_t cbp_tab[64][2] = {
39 {63, 0},{15,15},{31,63},{47,31},{ 0,16},{14,32},{13,47},{11,13},
40 { 7,14},{ 5,11},{10,12},{ 8, 5},{12,10},{61, 7},{ 4,48},{55, 3},
41 { 1, 2},{ 2, 8},{59, 4},{ 3, 1},{62,61},{ 9,55},{ 6,59},{29,62},
42 {45,29},{51,27},{23,23},{39,19},{27,30},{46,28},{53, 9},{30, 6},
43 {43,60},{37,21},{60,44},{16,26},{21,51},{28,35},{19,18},{35,20},
44 {42,24},{26,53},{44,17},{32,37},{58,39},{24,45},{20,58},{17,43},
45 {18,42},{48,46},{22,36},{33,33},{25,34},{49,40},{40,52},{36,49},
46 {34,50},{50,56},{52,25},{54,22},{41,54},{56,57},{38,41},{57,38}
49 /*****************************************************************************
51 * motion vector prediction
53 ****************************************************************************/
55 static inline void store_mvs(AVSContext *h) {
56 h->col_mv[h->mbidx*4 + 0] = h->mv[MV_FWD_X0];
57 h->col_mv[h->mbidx*4 + 1] = h->mv[MV_FWD_X1];
58 h->col_mv[h->mbidx*4 + 2] = h->mv[MV_FWD_X2];
59 h->col_mv[h->mbidx*4 + 3] = h->mv[MV_FWD_X3];
62 static inline void mv_pred_direct(AVSContext *h, cavs_vector *pmv_fw,
63 cavs_vector *col_mv) {
64 cavs_vector *pmv_bw = pmv_fw + MV_BWD_OFFS;
65 int den = h->direct_den[col_mv->ref];
66 int m = col_mv->x >> 31;
68 pmv_fw->dist = h->dist[1];
69 pmv_bw->dist = h->dist[0];
72 /* scale the co-located motion vector according to its temporal span */
73 pmv_fw->x = (((den+(den*col_mv->x*pmv_fw->dist^m)-m-1)>>14)^m)-m;
74 pmv_bw->x = m-(((den+(den*col_mv->x*pmv_bw->dist^m)-m-1)>>14)^m);
76 pmv_fw->y = (((den+(den*col_mv->y*pmv_fw->dist^m)-m-1)>>14)^m)-m;
77 pmv_bw->y = m-(((den+(den*col_mv->y*pmv_bw->dist^m)-m-1)>>14)^m);
80 static inline void mv_pred_sym(AVSContext *h, cavs_vector *src, enum cavs_block size) {
81 cavs_vector *dst = src + MV_BWD_OFFS;
83 /* backward mv is the scaled and negated forward mv */
84 dst->x = -((src->x * h->sym_factor + 256) >> 9);
85 dst->y = -((src->y * h->sym_factor + 256) >> 9);
87 dst->dist = h->dist[0];
91 /*****************************************************************************
93 * residual data decoding
95 ****************************************************************************/
97 /** kth-order exponential golomb code */
98 static inline int get_ue_code(GetBitContext *gb, int order) {
100 int ret = get_ue_golomb(gb) << order;
101 return ret + get_bits(gb,order);
103 return get_ue_golomb(gb);
107 * decode coefficients from one 8x8 block, dequantize, inverse transform
108 * and add them to sample block
109 * @param r pointer to 2D VLC table
110 * @param esc_golomb_order escape codes are k-golomb with this order k
111 * @param qp quantizer
112 * @param dst location of sample block
113 * @param stride line stride in frame buffer
115 static int decode_residual_block(AVSContext *h, GetBitContext *gb,
116 const struct dec_2dvlc *r, int esc_golomb_order,
117 int qp, uint8_t *dst, int stride) {
118 int i, level_code, esc_code, level, run, mask;
119 DCTELEM level_buf[65];
121 DCTELEM *block = h->block;
124 level_code = get_ue_code(gb,r->golomb_order);
125 if(level_code >= ESCAPE_CODE) {
126 run = ((level_code - ESCAPE_CODE) >> 1) + 1;
127 esc_code = get_ue_code(gb,esc_golomb_order);
128 level = esc_code + (run > r->max_run ? 1 : r->level_add[run]);
129 while(level > r->inc_limit)
131 mask = -(level_code & 1);
132 level = (level^mask) - mask;
133 } else if (level_code >= 0) {
134 level = r->rltab[level_code][0];
135 if(!level) //end of block signal
137 run = r->rltab[level_code][1];
138 r += r->rltab[level_code][2];
142 level_buf[i] = level;
145 if(dequant(h,level_buf, run_buf, block, ff_cavs_dequant_mul[qp],
146 ff_cavs_dequant_shift[qp], i))
148 h->cdsp.cavs_idct8_add(dst,block,stride);
149 h->s.dsp.clear_block(block);
154 static inline void decode_residual_chroma(AVSContext *h) {
156 decode_residual_block(h,&h->s.gb,ff_cavs_chroma_dec,0,
157 ff_cavs_chroma_qp[h->qp],h->cu,h->c_stride);
159 decode_residual_block(h,&h->s.gb,ff_cavs_chroma_dec,0,
160 ff_cavs_chroma_qp[h->qp],h->cv,h->c_stride);
163 static inline int decode_residual_inter(AVSContext *h) {
166 /* get coded block pattern */
167 int cbp= get_ue_golomb(&h->s.gb);
169 av_log(h->s.avctx, AV_LOG_ERROR, "illegal inter cbp\n");
172 h->cbp = cbp_tab[cbp][1];
175 if(h->cbp && !h->qp_fixed)
176 h->qp = (h->qp + get_se_golomb(&h->s.gb)) & 63;
177 for(block=0;block<4;block++)
178 if(h->cbp & (1<<block))
179 decode_residual_block(h,&h->s.gb,ff_cavs_inter_dec,0,h->qp,
180 h->cy + h->luma_scan[block], h->l_stride);
181 decode_residual_chroma(h);
186 /*****************************************************************************
190 ****************************************************************************/
192 static int decode_mb_i(AVSContext *h, int cbp_code) {
193 GetBitContext *gb = &h->s.gb;
194 unsigned pred_mode_uv;
197 uint8_t *left = NULL;
202 /* get intra prediction modes from stream */
203 for(block=0;block<4;block++) {
205 int pos = ff_cavs_scan3x3[block];
207 nA = h->pred_mode_Y[pos-1];
208 nB = h->pred_mode_Y[pos-3];
209 predpred = FFMIN(nA,nB);
210 if(predpred == NOT_AVAIL) // if either is not available
211 predpred = INTRA_L_LP;
213 int rem_mode= get_bits(gb, 2);
214 predpred = rem_mode + (rem_mode >= predpred);
216 h->pred_mode_Y[pos] = predpred;
218 pred_mode_uv = get_ue_golomb(gb);
219 if(pred_mode_uv > 6) {
220 av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra chroma pred mode\n");
223 ff_cavs_modify_mb_i(h, &pred_mode_uv);
225 /* get coded block pattern */
226 if(h->pic_type == AV_PICTURE_TYPE_I)
227 cbp_code = get_ue_golomb(gb);
229 av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra cbp\n");
232 h->cbp = cbp_tab[cbp_code][0];
233 if(h->cbp && !h->qp_fixed)
234 h->qp = (h->qp + get_se_golomb(gb)) & 63; //qp_delta
236 /* luma intra prediction interleaved with residual decode/transform/add */
237 for(block=0;block<4;block++) {
238 d = h->cy + h->luma_scan[block];
239 ff_cavs_load_intra_pred_luma(h, top, &left, block);
240 h->intra_pred_l[h->pred_mode_Y[ff_cavs_scan3x3[block]]]
241 (d, top, left, h->l_stride);
242 if(h->cbp & (1<<block))
243 decode_residual_block(h,gb,ff_cavs_intra_dec,1,h->qp,d,h->l_stride);
246 /* chroma intra prediction */
247 ff_cavs_load_intra_pred_chroma(h);
248 h->intra_pred_c[pred_mode_uv](h->cu, &h->top_border_u[h->mbx*10],
249 h->left_border_u, h->c_stride);
250 h->intra_pred_c[pred_mode_uv](h->cv, &h->top_border_v[h->mbx*10],
251 h->left_border_v, h->c_stride);
253 decode_residual_chroma(h);
254 ff_cavs_filter(h,I_8X8);
259 static void decode_mb_p(AVSContext *h, enum cavs_mb mb_type) {
260 GetBitContext *gb = &h->s.gb;
266 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_PSKIP, BLK_16X16, 0);
269 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
270 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16,ref[0]);
273 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
274 ref[2] = h->ref_flag ? 0 : get_bits1(gb);
275 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP, BLK_16X8, ref[0]);
276 ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, ref[2]);
279 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
280 ref[1] = h->ref_flag ? 0 : get_bits1(gb);
281 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, ref[0]);
282 ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_TOPRIGHT,BLK_8X16, ref[1]);
285 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
286 ref[1] = h->ref_flag ? 0 : get_bits1(gb);
287 ref[2] = h->ref_flag ? 0 : get_bits1(gb);
288 ref[3] = h->ref_flag ? 0 : get_bits1(gb);
289 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_MEDIAN, BLK_8X8, ref[0]);
290 ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_MEDIAN, BLK_8X8, ref[1]);
291 ff_cavs_mv(h, MV_FWD_X2, MV_FWD_X1, MV_PRED_MEDIAN, BLK_8X8, ref[2]);
292 ff_cavs_mv(h, MV_FWD_X3, MV_FWD_X0, MV_PRED_MEDIAN, BLK_8X8, ref[3]);
294 ff_cavs_inter(h, mb_type);
295 set_intra_mode_default(h);
297 if(mb_type != P_SKIP)
298 decode_residual_inter(h);
299 ff_cavs_filter(h,mb_type);
300 h->col_type_base[h->mbidx] = mb_type;
303 static void decode_mb_b(AVSContext *h, enum cavs_mb mb_type) {
305 enum cavs_sub_mb sub_type[4];
311 h->mv[MV_FWD_X0] = ff_cavs_dir_mv;
312 set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);
313 h->mv[MV_BWD_X0] = ff_cavs_dir_mv;
314 set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);
318 if(!h->col_type_base[h->mbidx]) {
319 /* intra MB at co-location, do in-plane prediction */
320 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_BSKIP, BLK_16X16, 1);
321 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_BSKIP, BLK_16X16, 0);
323 /* direct prediction from co-located P MB, block-wise */
324 for(block=0;block<4;block++)
325 mv_pred_direct(h,&h->mv[mv_scan[block]],
326 &h->col_mv[h->mbidx*4 + block]);
329 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);
332 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);
333 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X16);
336 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_MEDIAN, BLK_16X16, 0);
339 for(block=0;block<4;block++)
340 sub_type[block] = get_bits(&h->s.gb,2);
341 for(block=0;block<4;block++) {
342 switch(sub_type[block]) {
344 if(!h->col_type_base[h->mbidx]) {
345 /* intra MB at co-location, do in-plane prediction */
346 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,
347 MV_PRED_BSKIP, BLK_8X8, 1);
348 ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS,
349 mv_scan[block]-3+MV_BWD_OFFS,
350 MV_PRED_BSKIP, BLK_8X8, 0);
352 mv_pred_direct(h,&h->mv[mv_scan[block]],
353 &h->col_mv[h->mbidx*4 + block]);
356 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,
357 MV_PRED_MEDIAN, BLK_8X8, 1);
360 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,
361 MV_PRED_MEDIAN, BLK_8X8, 1);
362 mv_pred_sym(h, &h->mv[mv_scan[block]], BLK_8X8);
366 for(block=0;block<4;block++) {
367 if(sub_type[block] == B_SUB_BWD)
368 ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS,
369 mv_scan[block]+MV_BWD_OFFS-3,
370 MV_PRED_MEDIAN, BLK_8X8, 0);
374 assert((mb_type > B_SYM_16X16) && (mb_type < B_8X8));
375 flags = ff_cavs_partition_flags[mb_type];
376 if(mb_type & 1) { /* 16x8 macroblock types */
378 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP, BLK_16X8, 1);
380 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X8);
382 ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, 1);
384 mv_pred_sym(h, &h->mv[MV_FWD_X2], BLK_16X8);
386 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_TOP, BLK_16X8, 0);
388 ff_cavs_mv(h, MV_BWD_X2, MV_BWD_A1, MV_PRED_LEFT, BLK_16X8, 0);
389 } else { /* 8x16 macroblock types */
391 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, 1);
393 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_8X16);
395 ff_cavs_mv(h,MV_FWD_X1,MV_FWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,1);
397 mv_pred_sym(h, &h->mv[MV_FWD_X1], BLK_8X16);
399 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_B3, MV_PRED_LEFT, BLK_8X16, 0);
401 ff_cavs_mv(h,MV_BWD_X1,MV_BWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,0);
404 ff_cavs_inter(h, mb_type);
405 set_intra_mode_default(h);
406 if(mb_type != B_SKIP)
407 decode_residual_inter(h);
408 ff_cavs_filter(h,mb_type);
411 /*****************************************************************************
415 ****************************************************************************/
417 static inline int decode_slice_header(AVSContext *h, GetBitContext *gb) {
419 av_log(h->s.avctx, AV_LOG_ERROR, "unexpected start code 0x%02x\n", h->stc);
421 h->mbidx = h->mby*h->mb_width;
423 /* mark top macroblocks as unavailable */
424 h->flags &= ~(B_AVAIL|C_AVAIL);
425 if((h->mby == 0) && (!h->qp_fixed)){
426 h->qp_fixed = get_bits1(gb);
427 h->qp = get_bits(gb,6);
429 /* inter frame or second slice can have weighting params */
430 if((h->pic_type != AV_PICTURE_TYPE_I) || (!h->pic_structure && h->mby >= h->mb_width/2))
431 if(get_bits1(gb)) { //slice_weighting_flag
432 av_log(h->s.avctx, AV_LOG_ERROR,
433 "weighted prediction not yet supported\n");
438 static inline int check_for_slice(AVSContext *h) {
439 GetBitContext *gb = &h->s.gb;
444 align = (-get_bits_count(gb)) & 7;
445 /* check for stuffing byte */
446 if(!align && (show_bits(gb,8) == 0x80))
448 if((show_bits_long(gb,24+align) & 0xFFFFFF) == 0x000001) {
449 skip_bits_long(gb,24+align);
450 h->stc = get_bits(gb,8);
451 if (h->stc >= h->mb_height)
453 decode_slice_header(h,gb);
459 /*****************************************************************************
463 ****************************************************************************/
465 static int decode_pic(AVSContext *h) {
466 MpegEncContext *s = &h->s;
468 enum cavs_mb mb_type;
470 if (!s->context_initialized) {
471 s->avctx->idct_algo = FF_IDCT_CAVS;
472 if (MPV_common_init(s) < 0)
474 ff_init_scantable(s->dsp.idct_permutation,&h->scantable,ff_zigzag_direct);
476 skip_bits(&s->gb,16);//bbv_dwlay
477 if(h->stc == PIC_PB_START_CODE) {
478 h->pic_type = get_bits(&s->gb,2) + AV_PICTURE_TYPE_I;
479 if(h->pic_type > AV_PICTURE_TYPE_B) {
480 av_log(s->avctx, AV_LOG_ERROR, "illegal picture type\n");
483 /* make sure we have the reference frames we need */
484 if(!h->DPB[0].f.data[0] ||
485 (!h->DPB[1].f.data[0] && h->pic_type == AV_PICTURE_TYPE_B))
488 h->pic_type = AV_PICTURE_TYPE_I;
489 if(get_bits1(&s->gb))
490 skip_bits(&s->gb,24);//time_code
491 /* old sample clips were all progressive and no low_delay,
492 bump stream revision if detected otherwise */
493 if (s->low_delay || !(show_bits(&s->gb,9) & 1))
494 h->stream_revision = 1;
495 /* similarly test top_field_first and repeat_first_field */
496 else if(show_bits(&s->gb,11) & 3)
497 h->stream_revision = 1;
498 if(h->stream_revision > 0)
499 skip_bits(&s->gb,1); //marker_bit
501 /* release last B frame */
502 if(h->picture.f.data[0])
503 s->avctx->release_buffer(s->avctx, (AVFrame *)&h->picture);
505 s->avctx->get_buffer(s->avctx, (AVFrame *)&h->picture);
507 h->picture.poc = get_bits(&s->gb,8)*2;
509 /* get temporal distances and MV scaling factors */
510 if(h->pic_type != AV_PICTURE_TYPE_B) {
511 h->dist[0] = (h->picture.poc - h->DPB[0].poc + 512) % 512;
513 h->dist[0] = (h->DPB[0].poc - h->picture.poc + 512) % 512;
515 h->dist[1] = (h->picture.poc - h->DPB[1].poc + 512) % 512;
516 h->scale_den[0] = h->dist[0] ? 512/h->dist[0] : 0;
517 h->scale_den[1] = h->dist[1] ? 512/h->dist[1] : 0;
518 if(h->pic_type == AV_PICTURE_TYPE_B) {
519 h->sym_factor = h->dist[0]*h->scale_den[1];
521 h->direct_den[0] = h->dist[0] ? 16384/h->dist[0] : 0;
522 h->direct_den[1] = h->dist[1] ? 16384/h->dist[1] : 0;
526 get_ue_golomb(&s->gb); //bbv_check_times
527 h->progressive = get_bits1(&s->gb);
528 h->pic_structure = 1;
530 h->pic_structure = get_bits1(&s->gb);
531 if(!h->pic_structure && h->stc == PIC_PB_START_CODE)
532 skip_bits1(&s->gb); //advanced_pred_mode_disable
533 skip_bits1(&s->gb); //top_field_first
534 skip_bits1(&s->gb); //repeat_first_field
535 h->qp_fixed = get_bits1(&s->gb);
536 h->qp = get_bits(&s->gb,6);
537 if(h->pic_type == AV_PICTURE_TYPE_I) {
538 if(!h->progressive && !h->pic_structure)
539 skip_bits1(&s->gb);//what is this?
540 skip_bits(&s->gb,4); //reserved bits
542 if(!(h->pic_type == AV_PICTURE_TYPE_B && h->pic_structure == 1))
543 h->ref_flag = get_bits1(&s->gb);
544 skip_bits(&s->gb,4); //reserved bits
545 h->skip_mode_flag = get_bits1(&s->gb);
547 h->loop_filter_disable = get_bits1(&s->gb);
548 if(!h->loop_filter_disable && get_bits1(&s->gb)) {
549 h->alpha_offset = get_se_golomb(&s->gb);
550 h->beta_offset = get_se_golomb(&s->gb);
552 h->alpha_offset = h->beta_offset = 0;
554 if(h->pic_type == AV_PICTURE_TYPE_I) {
558 } while(ff_cavs_next_mb(h));
559 } else if(h->pic_type == AV_PICTURE_TYPE_P) {
561 if(check_for_slice(h))
563 if(h->skip_mode_flag && (skip_count < 0))
564 skip_count = get_ue_golomb(&s->gb);
565 if(h->skip_mode_flag && skip_count--) {
566 decode_mb_p(h,P_SKIP);
568 mb_type = get_ue_golomb(&s->gb) + P_SKIP + h->skip_mode_flag;
570 decode_mb_i(h, mb_type - P_8X8 - 1);
572 decode_mb_p(h,mb_type);
574 } while(ff_cavs_next_mb(h));
575 } else { /* AV_PICTURE_TYPE_B */
577 if(check_for_slice(h))
579 if(h->skip_mode_flag && (skip_count < 0))
580 skip_count = get_ue_golomb(&s->gb);
581 if(h->skip_mode_flag && skip_count--) {
582 decode_mb_b(h,B_SKIP);
584 mb_type = get_ue_golomb(&s->gb) + B_SKIP + h->skip_mode_flag;
586 decode_mb_i(h, mb_type - B_8X8 - 1);
588 decode_mb_b(h,mb_type);
590 } while(ff_cavs_next_mb(h));
592 if(h->pic_type != AV_PICTURE_TYPE_B) {
593 if(h->DPB[1].f.data[0])
594 s->avctx->release_buffer(s->avctx, (AVFrame *)&h->DPB[1]);
595 h->DPB[1] = h->DPB[0];
596 h->DPB[0] = h->picture;
597 memset(&h->picture,0,sizeof(Picture));
602 /*****************************************************************************
604 * headers and interface
606 ****************************************************************************/
608 static int decode_seq_header(AVSContext *h) {
609 MpegEncContext *s = &h->s;
612 h->profile = get_bits(&s->gb,8);
613 h->level = get_bits(&s->gb,8);
614 skip_bits1(&s->gb); //progressive sequence
615 s->width = get_bits(&s->gb,14);
616 s->height = get_bits(&s->gb,14);
617 skip_bits(&s->gb,2); //chroma format
618 skip_bits(&s->gb,3); //sample_precision
619 h->aspect_ratio = get_bits(&s->gb,4);
620 frame_rate_code = get_bits(&s->gb,4);
621 skip_bits(&s->gb,18);//bit_rate_lower
622 skip_bits1(&s->gb); //marker_bit
623 skip_bits(&s->gb,12);//bit_rate_upper
624 s->low_delay = get_bits1(&s->gb);
625 h->mb_width = (s->width + 15) >> 4;
626 h->mb_height = (s->height + 15) >> 4;
627 h->s.avctx->time_base.den = avpriv_frame_rate_tab[frame_rate_code].num;
628 h->s.avctx->time_base.num = avpriv_frame_rate_tab[frame_rate_code].den;
629 h->s.avctx->width = s->width;
630 h->s.avctx->height = s->height;
632 ff_cavs_init_top_lines(h);
636 static void cavs_flush(AVCodecContext * avctx) {
637 AVSContext *h = avctx->priv_data;
641 static int cavs_decode_frame(AVCodecContext * avctx,void *data, int *data_size,
643 const uint8_t *buf = avpkt->data;
644 int buf_size = avpkt->size;
645 AVSContext *h = avctx->priv_data;
646 MpegEncContext *s = &h->s;
648 const uint8_t *buf_end;
649 const uint8_t *buf_ptr;
650 AVFrame *picture = data;
656 if (!s->low_delay && h->DPB[0].f.data[0]) {
657 *data_size = sizeof(AVPicture);
658 *picture = *(AVFrame *) &h->DPB[0];
664 buf_end = buf + buf_size;
666 buf_ptr = avpriv_mpv_find_start_code(buf_ptr,buf_end, &stc);
667 if((stc & 0xFFFFFE00) || buf_ptr == buf_end)
668 return FFMAX(0, buf_ptr - buf - s->parse_context.last_index);
669 input_size = (buf_end - buf_ptr)*8;
671 case CAVS_START_CODE:
672 init_get_bits(&s->gb, buf_ptr, input_size);
673 decode_seq_header(h);
675 case PIC_I_START_CODE:
676 if(!h->got_keyframe) {
677 if(h->DPB[0].f.data[0])
678 avctx->release_buffer(avctx, (AVFrame *)&h->DPB[0]);
679 if(h->DPB[1].f.data[0])
680 avctx->release_buffer(avctx, (AVFrame *)&h->DPB[1]);
683 case PIC_PB_START_CODE:
687 init_get_bits(&s->gb, buf_ptr, input_size);
691 *data_size = sizeof(AVPicture);
692 if(h->pic_type != AV_PICTURE_TYPE_B) {
693 if(h->DPB[1].f.data[0]) {
694 *picture = *(AVFrame *) &h->DPB[1];
699 *picture = *(AVFrame *) &h->picture;
702 //mpeg_decode_extension(avctx,buf_ptr, input_size);
704 case USER_START_CODE:
705 //mpeg_decode_user_data(avctx,buf_ptr, input_size);
708 if (stc <= SLICE_MAX_START_CODE) {
709 init_get_bits(&s->gb, buf_ptr, input_size);
710 decode_slice_header(h, &s->gb);
717 AVCodec ff_cavs_decoder = {
719 .type = AVMEDIA_TYPE_VIDEO,
721 .priv_data_size = sizeof(AVSContext),
722 .init = ff_cavs_init,
723 .close = ff_cavs_end,
724 .decode = cavs_decode_frame,
725 .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DELAY,
727 .long_name= NULL_IF_CONFIG_SMALL("Chinese AVS video (AVS1-P2, JiZhun profile)"),