/* * Chinese AVS video (AVS1-P2, JiZhun profile) decoder. * Copyright (c) 2006 Stefan Gehrer <stefan.gehrer@gmx.de> * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Chinese AVS video (AVS1-P2, JiZhun profile) decoder * @author Stefan Gehrer <stefan.gehrer@gmx.de> */ #include "avcodec.h" #include "get_bits.h" #include "golomb.h" #include "cavs.h" static const uint8_t mv_scan[4] = { MV_FWD_X0,MV_FWD_X1, MV_FWD_X2,MV_FWD_X3 }; static const uint8_t cbp_tab[64][2] = { {63, 0},{15,15},{31,63},{47,31},{ 0,16},{14,32},{13,47},{11,13}, { 7,14},{ 5,11},{10,12},{ 8, 5},{12,10},{61, 7},{ 4,48},{55, 3}, { 1, 2},{ 2, 8},{59, 4},{ 3, 1},{62,61},{ 9,55},{ 6,59},{29,62}, {45,29},{51,27},{23,23},{39,19},{27,30},{46,28},{53, 9},{30, 6}, {43,60},{37,21},{60,44},{16,26},{21,51},{28,35},{19,18},{35,20}, {42,24},{26,53},{44,17},{32,37},{58,39},{24,45},{20,58},{17,43}, {18,42},{48,46},{22,36},{33,33},{25,34},{49,40},{40,52},{36,49}, {34,50},{50,56},{52,25},{54,22},{41,54},{56,57},{38,41},{57,38} }; /***************************************************************************** * * motion vector prediction * ****************************************************************************/ static inline void store_mvs(AVSContext *h) { h->col_mv[h->mbidx*4 + 0] = h->mv[MV_FWD_X0]; h->col_mv[h->mbidx*4 + 1] = h->mv[MV_FWD_X1]; h->col_mv[h->mbidx*4 + 2] = h->mv[MV_FWD_X2]; h->col_mv[h->mbidx*4 + 3] = h->mv[MV_FWD_X3]; } static inline void mv_pred_direct(AVSContext *h, cavs_vector *pmv_fw, cavs_vector *col_mv) { cavs_vector *pmv_bw = pmv_fw + MV_BWD_OFFS; int den = h->direct_den[col_mv->ref]; int m = col_mv->x >> 31; pmv_fw->dist = h->dist[1]; pmv_bw->dist = h->dist[0]; pmv_fw->ref = 1; pmv_bw->ref = 0; /* scale the co-located motion vector according to its temporal span */ pmv_fw->x = (((den+(den*col_mv->x*pmv_fw->dist^m)-m-1)>>14)^m)-m; pmv_bw->x = m-(((den+(den*col_mv->x*pmv_bw->dist^m)-m-1)>>14)^m); m = col_mv->y >> 31; pmv_fw->y = (((den+(den*col_mv->y*pmv_fw->dist^m)-m-1)>>14)^m)-m; pmv_bw->y = m-(((den+(den*col_mv->y*pmv_bw->dist^m)-m-1)>>14)^m); } static inline void mv_pred_sym(AVSContext *h, cavs_vector *src, enum cavs_block size) { cavs_vector *dst = src + MV_BWD_OFFS; /* backward mv is the scaled and negated forward mv */ dst->x = -((src->x * h->sym_factor + 256) >> 9); dst->y = -((src->y * h->sym_factor + 256) >> 9); dst->ref = 0; dst->dist = h->dist[0]; set_mvs(dst, size); } /***************************************************************************** * * residual data decoding * ****************************************************************************/ /** kth-order exponential golomb code */ static inline int get_ue_code(GetBitContext *gb, int order) { if(order) { int ret = get_ue_golomb(gb) << order; return ret + get_bits(gb,order); } return get_ue_golomb(gb); } /** * decode coefficients from one 8x8 block, dequantize, inverse transform * and add them to sample block * @param r pointer to 2D VLC table * @param esc_golomb_order escape codes are k-golomb with this order k * @param qp quantizer * @param dst location of sample block * @param stride line stride in frame buffer */ static int decode_residual_block(AVSContext *h, GetBitContext *gb, const struct dec_2dvlc *r, int esc_golomb_order, int qp, uint8_t *dst, int stride) { int i, esc_code, level, mask; unsigned int level_code, run; DCTELEM level_buf[65]; uint8_t run_buf[65]; DCTELEM *block = h->block; for(i=0;i<65;i++) { level_code = get_ue_code(gb,r->golomb_order); if(level_code >= ESCAPE_CODE) { run = ((level_code - ESCAPE_CODE) >> 1) + 1; if(run > 64) return -1; esc_code = get_ue_code(gb,esc_golomb_order); level = esc_code + (run > r->max_run ? 1 : r->level_add[run]); while(level > r->inc_limit) r++; mask = -(level_code & 1); level = (level^mask) - mask; } else { level = r->rltab[level_code][0]; if(!level) //end of block signal break; run = r->rltab[level_code][1]; r += r->rltab[level_code][2]; } level_buf[i] = level; run_buf[i] = run; } if(dequant(h,level_buf, run_buf, block, ff_cavs_dequant_mul[qp], ff_cavs_dequant_shift[qp], i)) return -1; h->cdsp.cavs_idct8_add(dst,block,stride); h->s.dsp.clear_block(block); return 0; } static inline void decode_residual_chroma(AVSContext *h) { if(h->cbp & (1<<4)) decode_residual_block(h,&h->s.gb,ff_cavs_chroma_dec,0, ff_cavs_chroma_qp[h->qp],h->cu,h->c_stride); if(h->cbp & (1<<5)) decode_residual_block(h,&h->s.gb,ff_cavs_chroma_dec,0, ff_cavs_chroma_qp[h->qp],h->cv,h->c_stride); } static inline int decode_residual_inter(AVSContext *h) { int block; /* get coded block pattern */ int cbp= get_ue_golomb(&h->s.gb); if(cbp > 63U){ av_log(h->s.avctx, AV_LOG_ERROR, "illegal inter cbp\n"); return -1; } h->cbp = cbp_tab[cbp][1]; /* get quantizer */ if(h->cbp && !h->qp_fixed) h->qp = (h->qp + get_se_golomb(&h->s.gb)) & 63; for(block=0;block<4;block++) if(h->cbp & (1<<block)) decode_residual_block(h,&h->s.gb,ff_cavs_inter_dec,0,h->qp, h->cy + h->luma_scan[block], h->l_stride); decode_residual_chroma(h); return 0; } /***************************************************************************** * * macroblock level * ****************************************************************************/ static int decode_mb_i(AVSContext *h, int cbp_code) { GetBitContext *gb = &h->s.gb; unsigned pred_mode_uv; int block; uint8_t top[18]; uint8_t *left = NULL; uint8_t *d; ff_cavs_init_mb(h); /* get intra prediction modes from stream */ for(block=0;block<4;block++) { int nA,nB,predpred; int pos = ff_cavs_scan3x3[block]; nA = h->pred_mode_Y[pos-1]; nB = h->pred_mode_Y[pos-3]; predpred = FFMIN(nA,nB); if(predpred == NOT_AVAIL) // if either is not available predpred = INTRA_L_LP; if(!get_bits1(gb)){ int rem_mode= get_bits(gb, 2); predpred = rem_mode + (rem_mode >= predpred); } h->pred_mode_Y[pos] = predpred; } pred_mode_uv = get_ue_golomb(gb); if(pred_mode_uv > 6) { av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra chroma pred mode\n"); return -1; } ff_cavs_modify_mb_i(h, &pred_mode_uv); /* get coded block pattern */ if(h->pic_type == AV_PICTURE_TYPE_I) cbp_code = get_ue_golomb(gb); if(cbp_code > 63U){ av_log(h->s.avctx, AV_LOG_ERROR, "illegal intra cbp\n"); return -1; } h->cbp = cbp_tab[cbp_code][0]; if(h->cbp && !h->qp_fixed) h->qp = (h->qp + get_se_golomb(gb)) & 63; //qp_delta /* luma intra prediction interleaved with residual decode/transform/add */ for(block=0;block<4;block++) { d = h->cy + h->luma_scan[block]; ff_cavs_load_intra_pred_luma(h, top, &left, block); h->intra_pred_l[h->pred_mode_Y[ff_cavs_scan3x3[block]]] (d, top, left, h->l_stride); if(h->cbp & (1<<block)) decode_residual_block(h,gb,ff_cavs_intra_dec,1,h->qp,d,h->l_stride); } /* chroma intra prediction */ ff_cavs_load_intra_pred_chroma(h); h->intra_pred_c[pred_mode_uv](h->cu, &h->top_border_u[h->mbx*10], h->left_border_u, h->c_stride); h->intra_pred_c[pred_mode_uv](h->cv, &h->top_border_v[h->mbx*10], h->left_border_v, h->c_stride); decode_residual_chroma(h); ff_cavs_filter(h,I_8X8); set_mv_intra(h); return 0; } static void decode_mb_p(AVSContext *h, enum cavs_mb mb_type) { GetBitContext *gb = &h->s.gb; int ref[4]; ff_cavs_init_mb(h); switch(mb_type) { case P_SKIP: ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_PSKIP, BLK_16X16, 0); break; case P_16X16: ref[0] = h->ref_flag ? 0 : get_bits1(gb); ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16,ref[0]); break; case P_16X8: ref[0] = h->ref_flag ? 0 : get_bits1(gb); ref[2] = h->ref_flag ? 0 : get_bits1(gb); ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP, BLK_16X8, ref[0]); ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, ref[2]); break; case P_8X16: ref[0] = h->ref_flag ? 0 : get_bits1(gb); ref[1] = h->ref_flag ? 0 : get_bits1(gb); ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, ref[0]); ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_TOPRIGHT,BLK_8X16, ref[1]); break; case P_8X8: ref[0] = h->ref_flag ? 0 : get_bits1(gb); ref[1] = h->ref_flag ? 0 : get_bits1(gb); ref[2] = h->ref_flag ? 0 : get_bits1(gb); ref[3] = h->ref_flag ? 0 : get_bits1(gb); ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_MEDIAN, BLK_8X8, ref[0]); ff_cavs_mv(h, MV_FWD_X1, MV_FWD_C2, MV_PRED_MEDIAN, BLK_8X8, ref[1]); ff_cavs_mv(h, MV_FWD_X2, MV_FWD_X1, MV_PRED_MEDIAN, BLK_8X8, ref[2]); ff_cavs_mv(h, MV_FWD_X3, MV_FWD_X0, MV_PRED_MEDIAN, BLK_8X8, ref[3]); } ff_cavs_inter(h, mb_type); set_intra_mode_default(h); store_mvs(h); if(mb_type != P_SKIP) decode_residual_inter(h); ff_cavs_filter(h,mb_type); h->col_type_base[h->mbidx] = mb_type; } static void decode_mb_b(AVSContext *h, enum cavs_mb mb_type) { int block; enum cavs_sub_mb sub_type[4]; int flags; ff_cavs_init_mb(h); /* reset all MVs */ h->mv[MV_FWD_X0] = ff_cavs_dir_mv; set_mvs(&h->mv[MV_FWD_X0], BLK_16X16); h->mv[MV_BWD_X0] = ff_cavs_dir_mv; set_mvs(&h->mv[MV_BWD_X0], BLK_16X16); switch(mb_type) { case B_SKIP: case B_DIRECT: if(!h->col_type_base[h->mbidx]) { /* intra MB at co-location, do in-plane prediction */ ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_BSKIP, BLK_16X16, 1); ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_BSKIP, BLK_16X16, 0); } else /* direct prediction from co-located P MB, block-wise */ for(block=0;block<4;block++) mv_pred_direct(h,&h->mv[mv_scan[block]], &h->col_mv[h->mbidx*4 + block]); break; case B_FWD_16X16: ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1); break; case B_SYM_16X16: ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_MEDIAN, BLK_16X16, 1); mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X16); break; case B_BWD_16X16: ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_MEDIAN, BLK_16X16, 0); break; case B_8X8: for(block=0;block<4;block++) sub_type[block] = get_bits(&h->s.gb,2); for(block=0;block<4;block++) { switch(sub_type[block]) { case B_SUB_DIRECT: if(!h->col_type_base[h->mbidx]) { /* intra MB at co-location, do in-plane prediction */ ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3, MV_PRED_BSKIP, BLK_8X8, 1); ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS, mv_scan[block]-3+MV_BWD_OFFS, MV_PRED_BSKIP, BLK_8X8, 0); } else mv_pred_direct(h,&h->mv[mv_scan[block]], &h->col_mv[h->mbidx*4 + block]); break; case B_SUB_FWD: ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3, MV_PRED_MEDIAN, BLK_8X8, 1); break; case B_SUB_SYM: ff_cavs_mv(h, mv_scan[block], mv_scan[block]-3, MV_PRED_MEDIAN, BLK_8X8, 1); mv_pred_sym(h, &h->mv[mv_scan[block]], BLK_8X8); break; } } for(block=0;block<4;block++) { if(sub_type[block] == B_SUB_BWD) ff_cavs_mv(h, mv_scan[block]+MV_BWD_OFFS, mv_scan[block]+MV_BWD_OFFS-3, MV_PRED_MEDIAN, BLK_8X8, 0); } break; default: assert((mb_type > B_SYM_16X16) && (mb_type < B_8X8)); flags = ff_cavs_partition_flags[mb_type]; if(mb_type & 1) { /* 16x8 macroblock types */ if(flags & FWD0) ff_cavs_mv(h, MV_FWD_X0, MV_FWD_C2, MV_PRED_TOP, BLK_16X8, 1); if(flags & SYM0) mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_16X8); if(flags & FWD1) ff_cavs_mv(h, MV_FWD_X2, MV_FWD_A1, MV_PRED_LEFT, BLK_16X8, 1); if(flags & SYM1) mv_pred_sym(h, &h->mv[MV_FWD_X2], BLK_16X8); if(flags & BWD0) ff_cavs_mv(h, MV_BWD_X0, MV_BWD_C2, MV_PRED_TOP, BLK_16X8, 0); if(flags & BWD1) ff_cavs_mv(h, MV_BWD_X2, MV_BWD_A1, MV_PRED_LEFT, BLK_16X8, 0); } else { /* 8x16 macroblock types */ if(flags & FWD0) ff_cavs_mv(h, MV_FWD_X0, MV_FWD_B3, MV_PRED_LEFT, BLK_8X16, 1); if(flags & SYM0) mv_pred_sym(h, &h->mv[MV_FWD_X0], BLK_8X16); if(flags & FWD1) ff_cavs_mv(h,MV_FWD_X1,MV_FWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,1); if(flags & SYM1) mv_pred_sym(h, &h->mv[MV_FWD_X1], BLK_8X16); if(flags & BWD0) ff_cavs_mv(h, MV_BWD_X0, MV_BWD_B3, MV_PRED_LEFT, BLK_8X16, 0); if(flags & BWD1) ff_cavs_mv(h,MV_BWD_X1,MV_BWD_C2,MV_PRED_TOPRIGHT,BLK_8X16,0); } } ff_cavs_inter(h, mb_type); set_intra_mode_default(h); if(mb_type != B_SKIP) decode_residual_inter(h); ff_cavs_filter(h,mb_type); } /***************************************************************************** * * slice level * ****************************************************************************/ static inline int decode_slice_header(AVSContext *h, GetBitContext *gb) { if(h->stc > 0xAF) av_log(h->s.avctx, AV_LOG_ERROR, "unexpected start code 0x%02x\n", h->stc); h->mby = h->stc; h->mbidx = h->mby*h->mb_width; /* mark top macroblocks as unavailable */ h->flags &= ~(B_AVAIL|C_AVAIL); if((h->mby == 0) && (!h->qp_fixed)){ h->qp_fixed = get_bits1(gb); h->qp = get_bits(gb,6); } /* inter frame or second slice can have weighting params */ if((h->pic_type != AV_PICTURE_TYPE_I) || (!h->pic_structure && h->mby >= h->mb_width/2)) if(get_bits1(gb)) { //slice_weighting_flag av_log(h->s.avctx, AV_LOG_ERROR, "weighted prediction not yet supported\n"); } return 0; } static inline int check_for_slice(AVSContext *h) { GetBitContext *gb = &h->s.gb; int align; if(h->mbx) return 0; align = (-get_bits_count(gb)) & 7; /* check for stuffing byte */ if(!align && (show_bits(gb,8) == 0x80)) align = 8; if((show_bits_long(gb,24+align) & 0xFFFFFF) == 0x000001) { skip_bits_long(gb,24+align); h->stc = get_bits(gb,8); if (h->stc >= h->mb_height) return 0; decode_slice_header(h,gb); return 1; } return 0; } /***************************************************************************** * * frame level * ****************************************************************************/ static int decode_pic(AVSContext *h) { MpegEncContext *s = &h->s; int skip_count = -1; enum cavs_mb mb_type; if (!s->context_initialized) { s->avctx->idct_algo = FF_IDCT_CAVS; if (MPV_common_init(s) < 0) return -1; ff_init_scantable(s->dsp.idct_permutation,&h->scantable,ff_zigzag_direct); } skip_bits(&s->gb,16);//bbv_dwlay if(h->stc == PIC_PB_START_CODE) { h->pic_type = get_bits(&s->gb,2) + AV_PICTURE_TYPE_I; if(h->pic_type > AV_PICTURE_TYPE_B) { av_log(s->avctx, AV_LOG_ERROR, "illegal picture type\n"); return -1; } /* make sure we have the reference frames we need */ if(!h->DPB[0].f.data[0] || (!h->DPB[1].f.data[0] && h->pic_type == AV_PICTURE_TYPE_B)) return -1; } else { h->pic_type = AV_PICTURE_TYPE_I; if(get_bits1(&s->gb)) skip_bits(&s->gb,24);//time_code /* old sample clips were all progressive and no low_delay, bump stream revision if detected otherwise */ if (s->low_delay || !(show_bits(&s->gb,9) & 1)) h->stream_revision = 1; /* similarly test top_field_first and repeat_first_field */ else if(show_bits(&s->gb,11) & 3) h->stream_revision = 1; if(h->stream_revision > 0) skip_bits(&s->gb,1); //marker_bit } /* release last B frame */ if(h->picture.f.data[0]) s->avctx->release_buffer(s->avctx, (AVFrame *)&h->picture); s->avctx->get_buffer(s->avctx, (AVFrame *)&h->picture); ff_cavs_init_pic(h); h->picture.poc = get_bits(&s->gb,8)*2; /* get temporal distances and MV scaling factors */ if(h->pic_type != AV_PICTURE_TYPE_B) { h->dist[0] = (h->picture.poc - h->DPB[0].poc + 512) % 512; } else { h->dist[0] = (h->DPB[0].poc - h->picture.poc + 512) % 512; } h->dist[1] = (h->picture.poc - h->DPB[1].poc + 512) % 512; h->scale_den[0] = h->dist[0] ? 512/h->dist[0] : 0; h->scale_den[1] = h->dist[1] ? 512/h->dist[1] : 0; if(h->pic_type == AV_PICTURE_TYPE_B) { h->sym_factor = h->dist[0]*h->scale_den[1]; } else { h->direct_den[0] = h->dist[0] ? 16384/h->dist[0] : 0; h->direct_den[1] = h->dist[1] ? 16384/h->dist[1] : 0; } if(s->low_delay) get_ue_golomb(&s->gb); //bbv_check_times h->progressive = get_bits1(&s->gb); h->pic_structure = 1; if(!h->progressive) h->pic_structure = get_bits1(&s->gb); if(!h->pic_structure && h->stc == PIC_PB_START_CODE) skip_bits1(&s->gb); //advanced_pred_mode_disable skip_bits1(&s->gb); //top_field_first skip_bits1(&s->gb); //repeat_first_field h->qp_fixed = get_bits1(&s->gb); h->qp = get_bits(&s->gb,6); if(h->pic_type == AV_PICTURE_TYPE_I) { if(!h->progressive && !h->pic_structure) skip_bits1(&s->gb);//what is this? skip_bits(&s->gb,4); //reserved bits } else { if(!(h->pic_type == AV_PICTURE_TYPE_B && h->pic_structure == 1)) h->ref_flag = get_bits1(&s->gb); skip_bits(&s->gb,4); //reserved bits h->skip_mode_flag = get_bits1(&s->gb); } h->loop_filter_disable = get_bits1(&s->gb); if(!h->loop_filter_disable && get_bits1(&s->gb)) { h->alpha_offset = get_se_golomb(&s->gb); h->beta_offset = get_se_golomb(&s->gb); } else { h->alpha_offset = h->beta_offset = 0; } if(h->pic_type == AV_PICTURE_TYPE_I) { do { check_for_slice(h); decode_mb_i(h, 0); } while(ff_cavs_next_mb(h)); } else if(h->pic_type == AV_PICTURE_TYPE_P) { do { if(check_for_slice(h)) skip_count = -1; if(h->skip_mode_flag && (skip_count < 0)) skip_count = get_ue_golomb(&s->gb); if(h->skip_mode_flag && skip_count--) { decode_mb_p(h,P_SKIP); } else { mb_type = get_ue_golomb(&s->gb) + P_SKIP + h->skip_mode_flag; if(mb_type > P_8X8) decode_mb_i(h, mb_type - P_8X8 - 1); else decode_mb_p(h,mb_type); } } while(ff_cavs_next_mb(h)); } else { /* AV_PICTURE_TYPE_B */ do { if(check_for_slice(h)) skip_count = -1; if(h->skip_mode_flag && (skip_count < 0)) skip_count = get_ue_golomb(&s->gb); if(h->skip_mode_flag && skip_count--) { decode_mb_b(h,B_SKIP); } else { mb_type = get_ue_golomb(&s->gb) + B_SKIP + h->skip_mode_flag; if(mb_type > B_8X8) decode_mb_i(h, mb_type - B_8X8 - 1); else decode_mb_b(h,mb_type); } } while(ff_cavs_next_mb(h)); } if(h->pic_type != AV_PICTURE_TYPE_B) { if(h->DPB[1].f.data[0]) s->avctx->release_buffer(s->avctx, (AVFrame *)&h->DPB[1]); h->DPB[1] = h->DPB[0]; h->DPB[0] = h->picture; memset(&h->picture,0,sizeof(Picture)); } return 0; } /***************************************************************************** * * headers and interface * ****************************************************************************/ static int decode_seq_header(AVSContext *h) { MpegEncContext *s = &h->s; int frame_rate_code; h->profile = get_bits(&s->gb,8); h->level = get_bits(&s->gb,8); skip_bits1(&s->gb); //progressive sequence s->width = get_bits(&s->gb,14); s->height = get_bits(&s->gb,14); skip_bits(&s->gb,2); //chroma format skip_bits(&s->gb,3); //sample_precision h->aspect_ratio = get_bits(&s->gb,4); frame_rate_code = get_bits(&s->gb,4); skip_bits(&s->gb,18);//bit_rate_lower skip_bits1(&s->gb); //marker_bit skip_bits(&s->gb,12);//bit_rate_upper s->low_delay = get_bits1(&s->gb); h->mb_width = (s->width + 15) >> 4; h->mb_height = (s->height + 15) >> 4; h->s.avctx->time_base.den = avpriv_frame_rate_tab[frame_rate_code].num; h->s.avctx->time_base.num = avpriv_frame_rate_tab[frame_rate_code].den; h->s.avctx->width = s->width; h->s.avctx->height = s->height; if(!h->top_qp) ff_cavs_init_top_lines(h); return 0; } static void cavs_flush(AVCodecContext * avctx) { AVSContext *h = avctx->priv_data; h->got_keyframe = 0; } static int cavs_decode_frame(AVCodecContext * avctx,void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; AVSContext *h = avctx->priv_data; MpegEncContext *s = &h->s; int input_size; const uint8_t *buf_end; const uint8_t *buf_ptr; AVFrame *picture = data; uint32_t stc = -1; s->avctx = avctx; if (buf_size == 0) { if (!s->low_delay && h->DPB[0].f.data[0]) { *data_size = sizeof(AVPicture); *picture = *(AVFrame *) &h->DPB[0]; } return 0; } buf_ptr = buf; buf_end = buf + buf_size; for(;;) { buf_ptr = avpriv_mpv_find_start_code(buf_ptr,buf_end, &stc); if((stc & 0xFFFFFE00) || buf_ptr == buf_end) return FFMAX(0, buf_ptr - buf - s->parse_context.last_index); input_size = (buf_end - buf_ptr)*8; switch(stc) { case CAVS_START_CODE: init_get_bits(&s->gb, buf_ptr, input_size); decode_seq_header(h); break; case PIC_I_START_CODE: if(!h->got_keyframe) { if(h->DPB[0].f.data[0]) avctx->release_buffer(avctx, (AVFrame *)&h->DPB[0]); if(h->DPB[1].f.data[0]) avctx->release_buffer(avctx, (AVFrame *)&h->DPB[1]); h->got_keyframe = 1; } case PIC_PB_START_CODE: *data_size = 0; if(!h->got_keyframe) break; init_get_bits(&s->gb, buf_ptr, input_size); h->stc = stc; if(decode_pic(h)) break; *data_size = sizeof(AVPicture); if(h->pic_type != AV_PICTURE_TYPE_B) { if(h->DPB[1].f.data[0]) { *picture = *(AVFrame *) &h->DPB[1]; } else { *data_size = 0; } } else *picture = *(AVFrame *) &h->picture; break; case EXT_START_CODE: //mpeg_decode_extension(avctx,buf_ptr, input_size); break; case USER_START_CODE: //mpeg_decode_user_data(avctx,buf_ptr, input_size); break; default: if (stc <= SLICE_MAX_START_CODE) { init_get_bits(&s->gb, buf_ptr, input_size); decode_slice_header(h, &s->gb); } break; } } } AVCodec ff_cavs_decoder = { .name = "cavs", .type = AVMEDIA_TYPE_VIDEO, .id = CODEC_ID_CAVS, .priv_data_size = sizeof(AVSContext), .init = ff_cavs_init, .close = ff_cavs_end, .decode = cavs_decode_frame, .capabilities = CODEC_CAP_DR1 | CODEC_CAP_DELAY, .flush= cavs_flush, .long_name= NULL_IF_CONFIG_SMALL("Chinese AVS video (AVS1-P2, JiZhun profile)"), };