static inline int parse_nal_units(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t *buf, int buf_size) { H264ParseContext *p = s->priv_data; const uint8_t *buf_end = buf + buf_size; H2645NAL nal = { NULL }; unsigned int pps_id; unsigned int slice_type; int state = -1, got_reset = 0; int field_poc[2]; int ret; /* set some sane default values */ s->pict_type = AV_PICTURE_TYPE_I; s->key_frame = 0; s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN; ff_h264_sei_uninit(&p->sei); if (!buf_size) return 0; for (;;) { const SPS *sps; int src_length, consumed; buf = avpriv_find_start_code(buf, buf_end, &state); if (buf >= buf_end) break; --buf; src_length = buf_end - buf; switch (state & 0x1f) { case H264_NAL_SLICE: case H264_NAL_IDR_SLICE: // Do not walk the whole buffer just to decode slice header if ((state & 0x1f) == H264_NAL_IDR_SLICE || ((state >> 5) & 0x3) == 0) { /* IDR or disposable slice * No need to decode many bytes because MMCOs shall not be present. */ if (src_length > 60) src_length = 60; } else { /* To decode up to MMCOs */ if (src_length > 1000) src_length = 1000; } break; } consumed = ff_h2645_extract_rbsp(buf, src_length, &nal); if (consumed < 0) break; ret = init_get_bits(&nal.gb, nal.data, nal.size * 8); if (ret < 0) goto fail; get_bits1(&nal.gb); nal.ref_idc = get_bits(&nal.gb, 2); nal.type = get_bits(&nal.gb, 5); switch (nal.type) { case H264_NAL_SPS: ff_h264_decode_seq_parameter_set(&nal.gb, avctx, &p->ps); break; case H264_NAL_PPS: ff_h264_decode_picture_parameter_set(&nal.gb, avctx, &p->ps, nal.size_bits); break; case H264_NAL_SEI: ff_h264_sei_decode(&p->sei, &nal.gb, &p->ps, avctx); break; case H264_NAL_IDR_SLICE: s->key_frame = 1; p->poc.prev_frame_num = 0; p->poc.prev_frame_num_offset = 0; p->poc.prev_poc_msb = p->poc.prev_poc_lsb = 0; /* fall through */ case H264_NAL_SLICE: get_ue_golomb(&nal.gb); // skip first_mb_in_slice slice_type = get_ue_golomb_31(&nal.gb); s->pict_type = ff_h264_golomb_to_pict_type[slice_type % 5]; if (p->sei.recovery_point.recovery_frame_cnt >= 0) { /* key frame, since recovery_frame_cnt is set */ s->key_frame = 1; } pps_id = get_ue_golomb(&nal.gb); if (pps_id >= MAX_PPS_COUNT) { av_log(avctx, AV_LOG_ERROR, "pps_id %u out of range\n", pps_id); goto fail; } if (!p->ps.pps_list[pps_id]) { av_log(avctx, AV_LOG_ERROR, "non-existing PPS %u referenced\n", pps_id); goto fail; } p->ps.pps = (const PPS*)p->ps.pps_list[pps_id]->data; if (!p->ps.sps_list[p->ps.pps->sps_id]) { av_log(avctx, AV_LOG_ERROR, "non-existing SPS %u referenced\n", p->ps.pps->sps_id); goto fail; } p->ps.sps = (SPS*)p->ps.sps_list[p->ps.pps->sps_id]->data; sps = p->ps.sps; p->poc.frame_num = get_bits(&nal.gb, sps->log2_max_frame_num); s->coded_width = 16 * sps->mb_width; s->coded_height = 16 * sps->mb_height; s->width = s->coded_width - (sps->crop_right + sps->crop_left); s->height = s->coded_height - (sps->crop_top + sps->crop_bottom); if (s->width <= 0 || s->height <= 0) { s->width = s->coded_width; s->height = s->coded_height; } switch (sps->bit_depth_luma) { case 9: if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P9; else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P9; else s->format = AV_PIX_FMT_YUV420P9; break; case 10: if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P10; else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P10; else s->format = AV_PIX_FMT_YUV420P10; break; case 8: if (sps->chroma_format_idc == 3) s->format = AV_PIX_FMT_YUV444P; else if (sps->chroma_format_idc == 2) s->format = AV_PIX_FMT_YUV422P; else s->format = AV_PIX_FMT_YUV420P; break; default: s->format = AV_PIX_FMT_NONE; } avctx->profile = ff_h264_get_profile(sps); avctx->level = sps->level_idc; if (sps->frame_mbs_only_flag) { p->picture_structure = PICT_FRAME; } else { if (get_bits1(&nal.gb)) { // field_pic_flag p->picture_structure = PICT_TOP_FIELD + get_bits1(&nal.gb); // bottom_field_flag } else { p->picture_structure = PICT_FRAME; } } if (nal.type == H264_NAL_IDR_SLICE) get_ue_golomb(&nal.gb); /* idr_pic_id */ if (sps->poc_type == 0) { p->poc.poc_lsb = get_bits(&nal.gb, sps->log2_max_poc_lsb); if (p->ps.pps->pic_order_present == 1 && p->picture_structure == PICT_FRAME) p->poc.delta_poc_bottom = get_se_golomb(&nal.gb); } if (sps->poc_type == 1 && !sps->delta_pic_order_always_zero_flag) { p->poc.delta_poc[0] = get_se_golomb(&nal.gb); if (p->ps.pps->pic_order_present == 1 && p->picture_structure == PICT_FRAME) p->poc.delta_poc[1] = get_se_golomb(&nal.gb); } /* Decode POC of this picture. * The prev_ values needed for decoding POC of the next picture are not set here. */ field_poc[0] = field_poc[1] = INT_MAX; ff_h264_init_poc(field_poc, &s->output_picture_number, sps, &p->poc, p->picture_structure, nal.ref_idc); /* Continue parsing to check if MMCO_RESET is present. * FIXME: MMCO_RESET could appear in non-first slice. * Maybe, we should parse all undisposable non-IDR slice of this * picture until encountering MMCO_RESET in a slice of it. */ if (nal.ref_idc && nal.type != H264_NAL_IDR_SLICE) { got_reset = scan_mmco_reset(s, &nal.gb, avctx); if (got_reset < 0) goto fail; } /* Set up the prev_ values for decoding POC of the next picture. */ p->poc.prev_frame_num = got_reset ? 0 : p->poc.frame_num; p->poc.prev_frame_num_offset = got_reset ? 0 : p->poc.frame_num_offset; if (nal.ref_idc != 0) { if (!got_reset) { p->poc.prev_poc_msb = p->poc.poc_msb; p->poc.prev_poc_lsb = p->poc.poc_lsb; } else { p->poc.prev_poc_msb = 0; p->poc.prev_poc_lsb = p->picture_structure == PICT_BOTTOM_FIELD ? 0 : field_poc[0]; } } if (sps->pic_struct_present_flag) { switch (p->sei.picture_timing.pic_struct) { case SEI_PIC_STRUCT_TOP_FIELD: case SEI_PIC_STRUCT_BOTTOM_FIELD: s->repeat_pict = 0; break; case SEI_PIC_STRUCT_FRAME: case SEI_PIC_STRUCT_TOP_BOTTOM: case SEI_PIC_STRUCT_BOTTOM_TOP: s->repeat_pict = 1; break; case SEI_PIC_STRUCT_TOP_BOTTOM_TOP: case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM: s->repeat_pict = 2; break; case SEI_PIC_STRUCT_FRAME_DOUBLING: s->repeat_pict = 3; break; case SEI_PIC_STRUCT_FRAME_TRIPLING: s->repeat_pict = 5; break; default: s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0; break; } } else { s->repeat_pict = p->picture_structure == PICT_FRAME ? 1 : 0; } if (p->picture_structure == PICT_FRAME) { s->picture_structure = AV_PICTURE_STRUCTURE_FRAME; if (sps->pic_struct_present_flag) { switch (p->sei.picture_timing.pic_struct) { case SEI_PIC_STRUCT_TOP_BOTTOM: case SEI_PIC_STRUCT_TOP_BOTTOM_TOP: s->field_order = AV_FIELD_TT; break; case SEI_PIC_STRUCT_BOTTOM_TOP: case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM: s->field_order = AV_FIELD_BB; break; default: s->field_order = AV_FIELD_PROGRESSIVE; break; } } else { if (field_poc[0] < field_poc[1]) s->field_order = AV_FIELD_TT; else if (field_poc[0] > field_poc[1]) s->field_order = AV_FIELD_BB; else s->field_order = AV_FIELD_PROGRESSIVE; } } else { if (p->picture_structure == PICT_TOP_FIELD) s->picture_structure = AV_PICTURE_STRUCTURE_TOP_FIELD; else s->picture_structure = AV_PICTURE_STRUCTURE_BOTTOM_FIELD; s->field_order = AV_FIELD_UNKNOWN; } av_freep(&nal.rbsp_buffer); return 0; /* no need to evaluate the rest */ } buf += consumed; } /* didn't find a picture! */ av_log(avctx, AV_LOG_ERROR, "missing picture in access unit\n"); fail: av_freep(&nal.rbsp_buffer); return -1; }