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00028 #include "avcodec.h"
00029 #include "bitstream.h"
00030 #include "golomb.h"
00031 #include "cavs.h"
00032
00033 static const uint8_t mv_scan[4] = {
00034 MV_FWD_X0,MV_FWD_X1,
00035 MV_FWD_X2,MV_FWD_X3
00036 };
00037
00038 static const uint8_t cbp_tab[64][2] = {
00039 {63, 0},{15,15},{31,63},{47,31},{ 0,16},{14,32},{13,47},{11,13},
00040 { 7,14},{ 5,11},{10,12},{ 8, 5},{12,10},{61, 7},{ 4,48},{55, 3},
00041 { 1, 2},{ 2, 8},{59, 4},{ 3, 1},{62,61},{ 9,55},{ 6,59},{29,62},
00042 {45,29},{51,27},{23,23},{39,19},{27,30},{46,28},{53, 9},{30, 6},
00043 {43,60},{37,21},{60,44},{16,26},{21,51},{28,35},{19,18},{35,20},
00044 {42,24},{26,53},{44,17},{32,37},{58,39},{24,45},{20,58},{17,43},
00045 {18,42},{48,46},{22,36},{33,33},{25,34},{49,40},{40,52},{36,49},
00046 {34,50},{50,56},{52,25},{54,22},{41,54},{56,57},{38,41},{57,38}
00047 };
00048
00049
00050
00051
00052
00053
00054
00055 static inline void store_mvs(AVSContext *h) {
00056 h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 0] = h->mv[MV_FWD_X0];
00057 h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 1] = h->mv[MV_FWD_X1];
00058 h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 2] = h->mv[MV_FWD_X2];
00059 h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + 3] = h->mv[MV_FWD_X3];
00060 }
00061
00062 static inline void mv_pred_direct(AVSContext *h, vector_t *pmv_fw,
00063 vector_t *col_mv) {
00064 vector_t *pmv_bw = pmv_fw + MV_BWD_OFFS;
00065 int den = h->direct_den[col_mv->ref];
00066 int m = col_mv->x >> 31;
00067
00068 pmv_fw->dist = h->dist[1];
00069 pmv_bw->dist = h->dist[0];
00070 pmv_fw->ref = 1;
00071 pmv_bw->ref = 0;
00072
00073 pmv_fw->x = (((den+(den*col_mv->x*pmv_fw->dist^m)-m-1)>>14)^m)-m;
00074 pmv_bw->x = m-(((den+(den*col_mv->x*pmv_bw->dist^m)-m-1)>>14)^m);
00075 m = col_mv->y >> 31;
00076 pmv_fw->y = (((den+(den*col_mv->y*pmv_fw->dist^m)-m-1)>>14)^m)-m;
00077 pmv_bw->y = m-(((den+(den*col_mv->y*pmv_bw->dist^m)-m-1)>>14)^m);
00078 }
00079
00080 static inline void mv_pred_sym(AVSContext *h, vector_t *src, enum block_t size) {
00081 vector_t *dst = src + MV_BWD_OFFS;
00082
00083
00084 dst->x = -((src->x * h->sym_factor + 256) >> 9);
00085 dst->y = -((src->y * h->sym_factor + 256) >> 9);
00086 dst->ref = 0;
00087 dst->dist = h->dist[0];
00088 set_mvs(dst, size);
00089 }
00090
00091
00092
00093
00094
00095
00096
00098 static inline int get_ue_code(GetBitContext *gb, int order) {
00099 if(order) {
00100 int ret = get_ue_golomb(gb) << order;
00101 return ret + get_bits(gb,order);
00102 }
00103 return get_ue_golomb(gb);
00104 }
00105
00115 static int decode_residual_block(AVSContext *h, GetBitContext *gb,
00116 const dec_2dvlc_t *r, int esc_golomb_order,
00117 int qp, uint8_t *dst, int stride) {
00118 int i, level_code, esc_code, level, run, mask;
00119 DCTELEM level_buf[64];
00120 uint8_t run_buf[64];
00121 DCTELEM *block = h->block;
00122
00123 for(i=0;i<65;i++) {
00124 level_code = get_ue_code(gb,r->golomb_order);
00125 if(level_code >= ESCAPE_CODE) {
00126 run = ((level_code - ESCAPE_CODE) >> 1) + 1;
00127 esc_code = get_ue_code(gb,esc_golomb_order);
00128 level = esc_code + (run > r->max_run ? 1 : r->level_add[run]);
00129 while(level > r->inc_limit)
00130 r++;
00131 mask = -(level_code & 1);
00132 level = (level^mask) - mask;
00133 } else {
00134 level = r->rltab[level_code][0];
00135 if(!level)
00136 break;
00137 run = r->rltab[level_code][1];
00138 r += r->rltab[level_code][2];
00139 }
00140 level_buf[i] = level;
00141 run_buf[i] = run;
00142 }
00143 if(dequant(h,level_buf, run_buf, block, ff_cavs_dequant_mul[qp],
00144 ff_cavs_dequant_shift[qp], i))
00145 return -1;
00146 h->s.dsp.cavs_idct8_add(dst,block,stride);
00147 return 0;
00148 }
00149
00150
00151 static inline void decode_residual_chroma(AVSContext *h) {
00152 if(h->cbp & (1<<4))
00153 decode_residual_block(h,&h->s.gb,ff_cavs_chroma_dec,0,
00154 ff_cavs_chroma_qp[h->qp],h->cu,h->c_stride);
00155 if(h->cbp & (1<<5))
00156 decode_residual_block(h,&h->s.gb,ff_cavs_chroma_dec,0,
00157 ff_cavs_chroma_qp[h->qp],h->cv,h->c_stride);
00158 }
00159
00160 static inline int decode_residual_inter(AVSContext *h) {
00161 int block;
00162
00163
00164 int cbp= get_ue_golomb(&h->s.gb);
00165 if(cbp > 63){
00166 av_log(h->s.avctx, AV_LOG_ERROR, "illegal inter cbp\n");
00167 return -1;
00168 }
00169 h->cbp = cbp_tab[cbp][1];
00170
00171
00172 if(h->cbp && !h->qp_fixed)
00173 h->qp = (h->qp + get_se_golomb(&h->s.gb)) & 63;
00174 for(block=0;block<4;block++)
00175 if(h->cbp & (1<<block))
00176 decode_residual_block(h,&h->s.gb,ff_cavs_inter_dec,0,h->qp,
00177 h->cy + h->luma_scan[block], h->l_stride);
00178 decode_residual_chroma(h);
00179
00180 return 0;
00181 }
00182
00183
00184
00185
00186
00187
00188
00189 static int decode_mb_i(AVSContext *h, int cbp_code) {
00190 GetBitContext *gb = &h->s.gb;
00191 int block, pred_mode_uv;
00192 uint8_t top[18];
00193 uint8_t *left = NULL;
00194 uint8_t *d;
00195
00196 ff_cavs_init_mb(h);
00197
00198
00199 for(block=0;block<4;block++) {
00200 int nA,nB,predpred;
00201 int pos = ff_cavs_scan3x3[block];
00202
00203 nA = h->pred_mode_Y[pos-1];
00204 nB = h->pred_mode_Y[pos-3];
00205 predpred = FFMIN(nA,nB);
00206 if(predpred == NOT_AVAIL)
00207 predpred = INTRA_L_LP;
00208 if(!get_bits1(gb)){
00209 int rem_mode= get_bits(gb, 2);
00210 predpred = rem_mode + (rem_mode >= predpred);
00211 }
00212 h->pred_mode_Y[pos] = predpred;
00213 }
00214 pred_mode_uv = get_ue_golomb(gb);
00215 if(pred_mode_uv > 6) {
00216 av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra chroma pred mode\n");
00217 return -1;
00218 }
00219 ff_cavs_modify_mb_i(h, &pred_mode_uv);
00220
00221
00222 if(h->pic_type == FF_I_TYPE)
00223 cbp_code = get_ue_golomb(gb);
00224 if(cbp_code > 63){
00225 av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra cbp\n");
00226 return -1;
00227 }
00228 h->cbp = cbp_tab[cbp_code][0];
00229 if(h->cbp && !h->qp_fixed)
00230 h->qp = (h->qp + get_se_golomb(gb)) & 63;
00231
00232
00233 for(block=0;block<4;block++) {
00234 d = h->cy + h->luma_scan[block];
00235 ff_cavs_load_intra_pred_luma(h, top, &left, block);
00236 h->intra_pred_l[h->pred_mode_Y[ff_cavs_scan3x3[block]]]
00237 (d, top, left, h->l_stride);
00238 if(h->cbp & (1<<block))
00239 decode_residual_block(h,gb,ff_cavs_intra_dec,1,h->qp,d,h->l_stride);
00240 }
00241
00242
00243 ff_cavs_load_intra_pred_chroma(h);
00244 h->intra_pred_c[pred_mode_uv](h->cu, &h->top_border_u[h->mbx*10],
00245 h->left_border_u, h->c_stride);
00246 h->intra_pred_c[pred_mode_uv](h->cv, &h->top_border_v[h->mbx*10],
00247 h->left_border_v, h->c_stride);
00248
00249 decode_residual_chroma(h);
00250 ff_cavs_filter(h,I_8X8);
00251 set_mv_intra(h);
00252 return 0;
00253 }
00254
00255 static void decode_mb_p(AVSContext *h, enum mb_t mb_type) {
00256 GetBitContext *gb = &h->s.gb;
00257 int ref[4];
00258
00259 ff_cavs_init_mb(h);
00260 switch(mb_type) {
00261 case P_SKIP:
00262 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_PSKIP, BLK_16X16, 0);
00263 break;
00264 case P_16X16:
00265 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
00266 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16,ref[0]);
00267 break;
00268 case P_16X8:
00269 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
00270 ref[2] = h->ref_flag ? 0 : get_bits1(gb);
00271 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP, BLK_16X8, ref[0]);
00272 ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, ref[2]);
00273 break;
00274 case P_8X16:
00275 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
00276 ref[1] = h->ref_flag ? 0 : get_bits1(gb);
00277 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, ref[0]);
00278 ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_TOPRIGHT,BLK_8X16, ref[1]);
00279 break;
00280 case P_8X8:
00281 ref[0] = h->ref_flag ? 0 : get_bits1(gb);
00282 ref[1] = h->ref_flag ? 0 : get_bits1(gb);
00283 ref[2] = h->ref_flag ? 0 : get_bits1(gb);
00284 ref[3] = h->ref_flag ? 0 : get_bits1(gb);
00285 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_MEDIAN, BLK_8X8, ref[0]);
00286 ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_MEDIAN, BLK_8X8, ref[1]);
00287 ff_cavs_mv(h, MV_FWD_X2, MV_FWD_X1, MV_PRED_MEDIAN, BLK_8X8, ref[2]);
00288 ff_cavs_mv(h, MV_FWD_X3, MV_FWD_X0, MV_PRED_MEDIAN, BLK_8X8, ref[3]);
00289 }
00290 ff_cavs_inter(h, mb_type);
00291 set_intra_mode_default(h);
00292 store_mvs(h);
00293 if(mb_type != P_SKIP)
00294 decode_residual_inter(h);
00295 ff_cavs_filter(h,mb_type);
00296 *h->col_type = mb_type;
00297 }
00298
00299 static void decode_mb_b(AVSContext *h, enum mb_t mb_type) {
00300 int block;
00301 enum sub_mb_t sub_type[4];
00302 int flags;
00303
00304 ff_cavs_init_mb(h);
00305
00306
00307 h->mv[MV_FWD_X0] = ff_cavs_dir_mv;
00308 set_mvs(&h->mv[MV_FWD_X0], BLK_16X16);
00309 h->mv[MV_BWD_X0] = ff_cavs_dir_mv;
00310 set_mvs(&h->mv[MV_BWD_X0], BLK_16X16);
00311 switch(mb_type) {
00312 case B_SKIP:
00313 case B_DIRECT:
00314 if(!(*h->col_type)) {
00315
00316 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_BSKIP, BLK_16X16, 1);
00317 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_BSKIP, BLK_16X16, 0);
00318 } else
00319
00320 for(block=0;block<4;block++)
00321 mv_pred_direct(h,&h->mv[mv_scan[block]],
00322 &h->col_mv[(h->mby*h->mb_width+h->mbx)*4 + block]);
00323 break;
00324 case B_FWD_16X16:
00325 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);
00326 break;
00327 case B_SYM_16X16:
00328 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1);
00329 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X16);
00330 break;
00331 case B_BWD_16X16:
00332 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_MEDIAN, BLK_16X16, 0);
00333 break;
00334 case B_8X8:
00335 for(block=0;block<4;block++)
00336 sub_type[block] = get_bits(&h->s.gb,2);
00337 for(block=0;block<4;block++) {
00338 switch(sub_type[block]) {
00339 case B_SUB_DIRECT:
00340 if(!(*h->col_type)) {
00341
00342 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,
00343 MV_PRED_BSKIP, BLK_8X8, 1);
00344 ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS,
00345 mv_scan[block]-3+MV_BWD_OFFS,
00346 MV_PRED_BSKIP, BLK_8X8, 0);
00347 } else
00348 mv_pred_direct(h,&h->mv[mv_scan[block]],
00349 &h->col_mv[(h->mby*h->mb_width + h->mbx)*4 + block]);
00350 break;
00351 case B_SUB_FWD:
00352 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,
00353 MV_PRED_MEDIAN, BLK_8X8, 1);
00354 break;
00355 case B_SUB_SYM:
00356 ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3,
00357 MV_PRED_MEDIAN, BLK_8X8, 1);
00358 mv_pred_sym(h, &h->mv[mv_scan[block]], BLK_8X8);
00359 break;
00360 }
00361 }
00362 for(block=0;block<4;block++) {
00363 if(sub_type[block] == B_SUB_BWD)
00364 ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS,
00365 mv_scan[block]+MV_BWD_OFFS-3,
00366 MV_PRED_MEDIAN, BLK_8X8, 0);
00367 }
00368 break;
00369 default:
00370 assert((mb_type > B_SYM_16X16) && (mb_type < B_8X8));
00371 flags = ff_cavs_partition_flags[mb_type];
00372 if(mb_type & 1) {
00373 if(flags & FWD0)
00374 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP, BLK_16X8, 1);
00375 if(flags & SYM0)
00376 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X8);
00377 if(flags & FWD1)
00378 ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, 1);
00379 if(flags & SYM1)
00380 mv_pred_sym(h, &h->mv[MV_FWD_X2], BLK_16X8);
00381 if(flags & BWD0)
00382 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_TOP, BLK_16X8, 0);
00383 if(flags & BWD1)
00384 ff_cavs_mv(h, MV_BWD_X2, MV_BWD_A1, MV_PRED_LEFT, BLK_16X8, 0);
00385 } else {
00386 if(flags & FWD0)
00387 ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, 1);
00388 if(flags & SYM0)
00389 mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_8X16);
00390 if(flags & FWD1)
00391 ff_cavs_mv(h,MV_FWD_X1,MV_FWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,1);
00392 if(flags & SYM1)
00393 mv_pred_sym(h, &h->mv[MV_FWD_X1], BLK_8X16);
00394 if(flags & BWD0)
00395 ff_cavs_mv(h, MV_BWD_X0, MV_BWD_B3, MV_PRED_LEFT, BLK_8X16, 0);
00396 if(flags & BWD1)
00397 ff_cavs_mv(h,MV_BWD_X1,MV_BWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,0);
00398 }
00399 }
00400 ff_cavs_inter(h, mb_type);
00401 set_intra_mode_default(h);
00402 if(mb_type != B_SKIP)
00403 decode_residual_inter(h);
00404 ff_cavs_filter(h,mb_type);
00405 }
00406
00407
00408
00409
00410
00411
00412
00413 static inline int decode_slice_header(AVSContext *h, GetBitContext *gb) {
00414 if(h->stc > 0xAF)
00415 av_log(h->s.avctx, AV_LOG_ERROR, "unexpected start code 0x%02x\n", h->stc);
00416 h->mby = h->stc;
00417 if((h->mby == 0) && (!h->qp_fixed)){
00418 h->qp_fixed = get_bits1(gb);
00419 h->qp = get_bits(gb,6);
00420 }
00421
00422 if((h->pic_type != FF_I_TYPE) || (!h->pic_structure && h->mby >= h->mb_width/2))
00423 if(get_bits1(gb)) {
00424 av_log(h->s.avctx, AV_LOG_ERROR,
00425 "weighted prediction not yet supported\n");
00426 }
00427 return 0;
00428 }
00429
00430 static inline void check_for_slice(AVSContext *h) {
00431 GetBitContext *gb = &h->s.gb;
00432 int align;
00433 align = (-get_bits_count(gb)) & 7;
00434 if((show_bits_long(gb,24+align) & 0xFFFFFF) == 0x000001) {
00435 skip_bits_long(gb,24+align);
00436 h->stc = get_bits(gb,8);
00437 decode_slice_header(h,gb);
00438 }
00439 }
00440
00441
00442
00443
00444
00445
00446
00447 static int decode_pic(AVSContext *h) {
00448 MpegEncContext *s = &h->s;
00449 int skip_count;
00450 enum mb_t mb_type;
00451
00452 if (!s->context_initialized) {
00453 s->avctx->idct_algo = FF_IDCT_CAVS;
00454 if (MPV_common_init(s) < 0)
00455 return -1;
00456 ff_init_scantable(s->dsp.idct_permutation,&h->scantable,ff_zigzag_direct);
00457 }
00458 skip_bits(&s->gb,16);
00459 if(h->stc == PIC_PB_START_CODE) {
00460 h->pic_type = get_bits(&s->gb,2) + FF_I_TYPE;
00461 if(h->pic_type > FF_B_TYPE) {
00462 av_log(s->avctx, AV_LOG_ERROR, "illegal picture type\n");
00463 return -1;
00464 }
00465
00466 if(!h->DPB[0].data[0] ||
00467 (!h->DPB[1].data[0] && h->pic_type == FF_B_TYPE))
00468 return -1;
00469 } else {
00470 h->pic_type = FF_I_TYPE;
00471 if(get_bits1(&s->gb))
00472 skip_bits(&s->gb,16);
00473 }
00474
00475 if(h->picture.data[0])
00476 s->avctx->release_buffer(s->avctx, (AVFrame *)&h->picture);
00477
00478 s->avctx->get_buffer(s->avctx, (AVFrame *)&h->picture);
00479 ff_cavs_init_pic(h);
00480 h->picture.poc = get_bits(&s->gb,8)*2;
00481
00482
00483 if(h->pic_type != FF_B_TYPE) {
00484 h->dist[0] = (h->picture.poc - h->DPB[0].poc + 512) % 512;
00485 } else {
00486 h->dist[0] = (h->DPB[0].poc - h->picture.poc + 512) % 512;
00487 }
00488 h->dist[1] = (h->picture.poc - h->DPB[1].poc + 512) % 512;
00489 h->scale_den[0] = h->dist[0] ? 512/h->dist[0] : 0;
00490 h->scale_den[1] = h->dist[1] ? 512/h->dist[1] : 0;
00491 if(h->pic_type == FF_B_TYPE) {
00492 h->sym_factor = h->dist[0]*h->scale_den[1];
00493 } else {
00494 h->direct_den[0] = h->dist[0] ? 16384/h->dist[0] : 0;
00495 h->direct_den[1] = h->dist[1] ? 16384/h->dist[1] : 0;
00496 }
00497
00498 if(s->low_delay)
00499 get_ue_golomb(&s->gb);
00500 h->progressive = get_bits1(&s->gb);
00501 if(h->progressive)
00502 h->pic_structure = 1;
00503 else if(!(h->pic_structure = get_bits1(&s->gb) && (h->stc == PIC_PB_START_CODE)) )
00504 skip_bits1(&s->gb);
00505 skip_bits1(&s->gb);
00506 skip_bits1(&s->gb);
00507 h->qp_fixed = get_bits1(&s->gb);
00508 h->qp = get_bits(&s->gb,6);
00509 if(h->pic_type == FF_I_TYPE) {
00510 if(!h->progressive && !h->pic_structure)
00511 skip_bits1(&s->gb);
00512 skip_bits(&s->gb,4);
00513 } else {
00514 if(!(h->pic_type == FF_B_TYPE && h->pic_structure == 1))
00515 h->ref_flag = get_bits1(&s->gb);
00516 skip_bits(&s->gb,4);
00517 h->skip_mode_flag = get_bits1(&s->gb);
00518 }
00519 h->loop_filter_disable = get_bits1(&s->gb);
00520 if(!h->loop_filter_disable && get_bits1(&s->gb)) {
00521 h->alpha_offset = get_se_golomb(&s->gb);
00522 h->beta_offset = get_se_golomb(&s->gb);
00523 } else {
00524 h->alpha_offset = h->beta_offset = 0;
00525 }
00526 check_for_slice(h);
00527 if(h->pic_type == FF_I_TYPE) {
00528 do {
00529 decode_mb_i(h, 0);
00530 } while(ff_cavs_next_mb(h));
00531 } else if(h->pic_type == FF_P_TYPE) {
00532 do {
00533 if(h->skip_mode_flag) {
00534 skip_count = get_ue_golomb(&s->gb);
00535 while(skip_count--) {
00536 decode_mb_p(h,P_SKIP);
00537 if(!ff_cavs_next_mb(h))
00538 goto done;
00539 }
00540 mb_type = get_ue_golomb(&s->gb) + P_16X16;
00541 } else
00542 mb_type = get_ue_golomb(&s->gb) + P_SKIP;
00543 if(mb_type > P_8X8) {
00544 decode_mb_i(h, mb_type - P_8X8 - 1);
00545 } else
00546 decode_mb_p(h,mb_type);
00547 } while(ff_cavs_next_mb(h));
00548 } else {
00549 do {
00550 if(h->skip_mode_flag) {
00551 skip_count = get_ue_golomb(&s->gb);
00552 while(skip_count--) {
00553 decode_mb_b(h,B_SKIP);
00554 if(!ff_cavs_next_mb(h))
00555 goto done;
00556 }
00557 mb_type = get_ue_golomb(&s->gb) + B_DIRECT;
00558 } else
00559 mb_type = get_ue_golomb(&s->gb) + B_SKIP;
00560 if(mb_type > B_8X8) {
00561 decode_mb_i(h, mb_type - B_8X8 - 1);
00562 } else
00563 decode_mb_b(h,mb_type);
00564 } while(ff_cavs_next_mb(h));
00565 }
00566 done:
00567 if(h->pic_type != FF_B_TYPE) {
00568 if(h->DPB[1].data[0])
00569 s->avctx->release_buffer(s->avctx, (AVFrame *)&h->DPB[1]);
00570 memcpy(&h->DPB[1], &h->DPB[0], sizeof(Picture));
00571 memcpy(&h->DPB[0], &h->picture, sizeof(Picture));
00572 memset(&h->picture,0,sizeof(Picture));
00573 }
00574 return 0;
00575 }
00576
00577
00578
00579
00580
00581
00582
00583 static int decode_seq_header(AVSContext *h) {
00584 MpegEncContext *s = &h->s;
00585 int frame_rate_code;
00586
00587 h->profile = get_bits(&s->gb,8);
00588 h->level = get_bits(&s->gb,8);
00589 skip_bits1(&s->gb);
00590 s->width = get_bits(&s->gb,14);
00591 s->height = get_bits(&s->gb,14);
00592 skip_bits(&s->gb,2);
00593 skip_bits(&s->gb,3);
00594 h->aspect_ratio = get_bits(&s->gb,4);
00595 frame_rate_code = get_bits(&s->gb,4);
00596 skip_bits(&s->gb,18);
00597 skip_bits1(&s->gb);
00598 skip_bits(&s->gb,12);
00599 s->low_delay = get_bits1(&s->gb);
00600 h->mb_width = (s->width + 15) >> 4;
00601 h->mb_height = (s->height + 15) >> 4;
00602 h->s.avctx->time_base.den = ff_frame_rate_tab[frame_rate_code].num;
00603 h->s.avctx->time_base.num = ff_frame_rate_tab[frame_rate_code].den;
00604 h->s.avctx->width = s->width;
00605 h->s.avctx->height = s->height;
00606 if(!h->top_qp)
00607 ff_cavs_init_top_lines(h);
00608 return 0;
00609 }
00610
00611 static void cavs_flush(AVCodecContext * avctx) {
00612 AVSContext *h = avctx->priv_data;
00613 h->got_keyframe = 0;
00614 }
00615
00616 static int cavs_decode_frame(AVCodecContext * avctx,void *data, int *data_size,
00617 const uint8_t * buf, int buf_size) {
00618 AVSContext *h = avctx->priv_data;
00619 MpegEncContext *s = &h->s;
00620 int input_size;
00621 const uint8_t *buf_end;
00622 const uint8_t *buf_ptr;
00623 AVFrame *picture = data;
00624 uint32_t stc = -1;
00625
00626 s->avctx = avctx;
00627
00628 if (buf_size == 0) {
00629 if(!s->low_delay && h->DPB[0].data[0]) {
00630 *data_size = sizeof(AVPicture);
00631 *picture = *(AVFrame *) &h->DPB[0];
00632 }
00633 return 0;
00634 }
00635
00636 buf_ptr = buf;
00637 buf_end = buf + buf_size;
00638 for(;;) {
00639 buf_ptr = ff_find_start_code(buf_ptr,buf_end, &stc);
00640 if(stc & 0xFFFFFE00)
00641 return FFMAX(0, buf_ptr - buf - s->parse_context.last_index);
00642 input_size = (buf_end - buf_ptr)*8;
00643 switch(stc) {
00644 case CAVS_START_CODE:
00645 init_get_bits(&s->gb, buf_ptr, input_size);
00646 decode_seq_header(h);
00647 break;
00648 case PIC_I_START_CODE:
00649 if(!h->got_keyframe) {
00650 if(h->DPB[0].data[0])
00651 avctx->release_buffer(avctx, (AVFrame *)&h->DPB[0]);
00652 if(h->DPB[1].data[0])
00653 avctx->release_buffer(avctx, (AVFrame *)&h->DPB[1]);
00654 h->got_keyframe = 1;
00655 }
00656 case PIC_PB_START_CODE:
00657 *data_size = 0;
00658 if(!h->got_keyframe)
00659 break;
00660 init_get_bits(&s->gb, buf_ptr, input_size);
00661 h->stc = stc;
00662 if(decode_pic(h))
00663 break;
00664 *data_size = sizeof(AVPicture);
00665 if(h->pic_type != FF_B_TYPE) {
00666 if(h->DPB[1].data[0]) {
00667 *picture = *(AVFrame *) &h->DPB[1];
00668 } else {
00669 *data_size = 0;
00670 }
00671 } else
00672 *picture = *(AVFrame *) &h->picture;
00673 break;
00674 case EXT_START_CODE:
00675
00676 break;
00677 case USER_START_CODE:
00678
00679 break;
00680 default:
00681 if (stc >= SLICE_MIN_START_CODE &&
00682 stc <= SLICE_MAX_START_CODE) {
00683 init_get_bits(&s->gb, buf_ptr, input_size);
00684 decode_slice_header(h, &s->gb);
00685 }
00686 break;
00687 }
00688 }
00689 }
00690
00691 AVCodec cavs_decoder = {
00692 "cavs",
00693 CODEC_TYPE_VIDEO,
00694 CODEC_ID_CAVS,
00695 sizeof(AVSContext),
00696 ff_cavs_init,
00697 NULL,
00698 ff_cavs_end,
00699 cavs_decode_frame,
00700 CODEC_CAP_DR1 | CODEC_CAP_DELAY,
00701 .flush= cavs_flush,
00702 };