static int mpeg1_decode_picture(AVCodecContext *avctx, const uint8_t *buf, int buf_size) { Mpeg1Context *s1 = avctx->priv_data; MpegEncContext *s = &s1->mpeg_enc_ctx; int ref, f_code, vbv_delay; init_get_bits(&s->gb, buf, buf_size * 8); ref = get_bits(&s->gb, 10); /* temporal ref */ s->pict_type = get_bits(&s->gb, 3); if (s->pict_type == 0 || s->pict_type > 3) return -1; vbv_delay = get_bits(&s->gb, 16); if (s->pict_type == AV_PICTURE_TYPE_P || s->pict_type == AV_PICTURE_TYPE_B) { s->full_pel[0] = get_bits1(&s->gb); f_code = get_bits(&s->gb, 3); if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM)) return -1; s->mpeg_f_code[0][0] = f_code; s->mpeg_f_code[0][1] = f_code; } if (s->pict_type == AV_PICTURE_TYPE_B) { s->full_pel[1] = get_bits1(&s->gb); f_code = get_bits(&s->gb, 3); if (f_code == 0 && (avctx->err_recognition & AV_EF_BITSTREAM)) return -1; s->mpeg_f_code[1][0] = f_code; s->mpeg_f_code[1][1] = f_code; } s->current_picture.f.pict_type = s->pict_type; s->current_picture.f.key_frame = s->pict_type == AV_PICTURE_TYPE_I; if (avctx->debug & FF_DEBUG_PICT_INFO) av_log(avctx, AV_LOG_DEBUG, "vbv_delay %d, ref %d type:%d\n", vbv_delay, ref, s->pict_type); s->y_dc_scale = 8; s->c_dc_scale = 8; return 0; }