2 * Copyright (c) 2016 Paul B Mahol
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "bytestream.h"
24 #include "dca_syncwords.h"
25 #include "libavutil/mem.h"
27 static int dca_core_filter(AVBSFContext *ctx, AVPacket *out)
32 int core_size = 0, ret;
34 ret = ff_bsf_get_packet(ctx, &in);
38 bytestream2_init(&gb, in->data, in->size);
39 syncword = bytestream2_get_be32(&gb);
40 bytestream2_skip(&gb, 1);
43 case DCA_SYNCWORD_CORE_BE:
44 core_size = ((bytestream2_get_be24(&gb) >> 4) & 0x3fff) + 1;
48 av_packet_move_ref(out, in);
51 if (core_size > 0 && core_size <= out->size) {
52 out->size = core_size;
58 static const enum AVCodecID codec_ids[] = {
59 AV_CODEC_ID_DTS, AV_CODEC_ID_NONE,
62 const AVBitStreamFilter ff_dca_core_bsf = {
64 .filter = dca_core_filter,
65 .codec_ids = codec_ids,