static int dnxhd_decode_header(DNXHDContext *ctx, const uint8_t *buf, int buf_size, int first_field) { static const uint8_t header_prefix[] = { 0x00, 0x00, 0x02, 0x80, 0x01 }; int i, cid; if (buf_size < 0x280) return -1; if (memcmp(buf, header_prefix, 5)) { av_log(ctx->avctx, AV_LOG_ERROR, "error in header\n"); return -1; } if (buf[5] & 2) { /* interlaced */ ctx->cur_field = buf[5] & 1; ctx->picture.interlaced_frame = 1; ctx->picture.top_field_first = first_field ^ ctx->cur_field; av_log(ctx->avctx, AV_LOG_DEBUG, "interlaced %d, cur field %d\n", buf[5] & 3, ctx->cur_field); } ctx->height = AV_RB16(buf + 0x18); ctx->width = AV_RB16(buf + 0x1a); av_dlog(ctx->avctx, "width %d, height %d\n", ctx->width, ctx->height); if (buf[0x21] & 0x40) { ctx->avctx->pix_fmt = AV_PIX_FMT_YUV422P10; ctx->avctx->bits_per_raw_sample = 10; if (ctx->bit_depth != 10) { ff_dsputil_init(&ctx->dsp, ctx->avctx); ctx->bit_depth = 10; ctx->decode_dct_block = dnxhd_decode_dct_block_10; } } else { ctx->avctx->pix_fmt = AV_PIX_FMT_YUV422P; ctx->avctx->bits_per_raw_sample = 8; if (ctx->bit_depth != 8) { ff_dsputil_init(&ctx->dsp, ctx->avctx); ctx->bit_depth = 8; ctx->decode_dct_block = dnxhd_decode_dct_block_8; } } cid = AV_RB32(buf + 0x28); av_dlog(ctx->avctx, "compression id %d\n", cid); if (dnxhd_init_vlc(ctx, cid) < 0) return -1; if (buf_size < ctx->cid_table->coding_unit_size) { av_log(ctx->avctx, AV_LOG_ERROR, "incorrect frame size\n"); return -1; } ctx->mb_width = ctx->width>>4; ctx->mb_height = buf[0x16d]; av_dlog(ctx->avctx, "mb width %d, mb height %d\n", ctx->mb_width, ctx->mb_height); if ((ctx->height+15)>>4 == ctx->mb_height && ctx->picture.interlaced_frame) ctx->height <<= 1; if (ctx->mb_height > 68 || (ctx->mb_height<<ctx->picture.interlaced_frame) > (ctx->height+15)>>4) { av_log(ctx->avctx, AV_LOG_ERROR, "mb height too big: %d\n", ctx->mb_height); return -1; } for (i = 0; i < ctx->mb_height; i++) { ctx->mb_scan_index[i] = AV_RB32(buf + 0x170 + (i<<2)); av_dlog(ctx->avctx, "mb scan index %d\n", ctx->mb_scan_index[i]); if (buf_size < ctx->mb_scan_index[i] + 0x280) { av_log(ctx->avctx, AV_LOG_ERROR, "invalid mb scan index\n"); return -1; } } return 0; }