1 /*
2 * HCA demuxer
3 * Copyright (c) 2020 Paul B Mahol
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "libavutil/intreadwrite.h"
23 #include "libavcodec/bytestream.h"
24
25 #include "avformat.h"
26 #include "internal.h"
27
hca_probe(const AVProbeData * p)28 static int hca_probe(const AVProbeData *p)
29 {
30 if (AV_RL32(p->buf) != MKTAG('H', 'C', 'A', 0))
31 return 0;
32
33 if (AV_RL32(p->buf + 8) != MKTAG('f', 'm', 't', 0))
34 return 0;
35
36 return AVPROBE_SCORE_MAX / 3;
37 }
38
hca_read_header(AVFormatContext * s)39 static int hca_read_header(AVFormatContext *s)
40 {
41 AVCodecParameters *par;
42 GetByteContext gb;
43 AVIOContext *pb = s->pb;
44 AVStream *st;
45 uint32_t chunk;
46 uint16_t version;
47 uint32_t block_count;
48 uint16_t block_size;
49 int ret;
50
51 avio_skip(pb, 4);
52 version = avio_rb16(pb);
53
54 s->internal->data_offset = avio_rb16(pb);
55 if (s->internal->data_offset <= 8)
56 return AVERROR_INVALIDDATA;
57
58 st = avformat_new_stream(s, NULL);
59 if (!st)
60 return AVERROR(ENOMEM);
61
62 par = st->codecpar;
63 ret = ff_alloc_extradata(par, s->internal->data_offset);
64 if (ret < 0)
65 return ret;
66
67 ret = avio_read(pb, par->extradata + 8, par->extradata_size - 8);
68 if (ret < par->extradata_size - 8)
69 return AVERROR(EIO);
70 AV_WL32(par->extradata, MKTAG('H', 'C', 'A', 0));
71 AV_WB16(par->extradata + 4, version);
72 AV_WB16(par->extradata + 6, s->internal->data_offset);
73
74 bytestream2_init(&gb, par->extradata + 8, par->extradata_size - 8);
75
76 if (bytestream2_get_le32(&gb) != MKTAG('f', 'm', 't', 0))
77 return AVERROR_INVALIDDATA;
78
79 par->codec_type = AVMEDIA_TYPE_AUDIO;
80 par->codec_id = AV_CODEC_ID_HCA;
81 par->codec_tag = 0;
82 par->channels = bytestream2_get_byte(&gb);
83 par->sample_rate = bytestream2_get_be24(&gb);
84 block_count = bytestream2_get_be32(&gb);
85 bytestream2_skip(&gb, 4);
86 chunk = bytestream2_get_le32(&gb);
87 if (chunk == MKTAG('c', 'o', 'm', 'p')) {
88 block_size = bytestream2_get_be16(&gb);
89 } else if (chunk == MKTAG('d', 'e', 'c', 0)) {
90 block_size = bytestream2_get_be16(&gb);
91 } else {
92 return AVERROR_INVALIDDATA;
93 }
94
95 if (block_size < 8)
96 return AVERROR_INVALIDDATA;
97 par->block_align = block_size;
98 st->duration = 1024 * block_count;
99
100 avio_seek(pb, s->internal->data_offset, SEEK_SET);
101 avpriv_set_pts_info(st, 64, 1, par->sample_rate);
102
103 return 0;
104 }
105
hca_read_packet(AVFormatContext * s,AVPacket * pkt)106 static int hca_read_packet(AVFormatContext *s, AVPacket *pkt)
107 {
108 AVCodecParameters *par = s->streams[0]->codecpar;
109 int ret;
110
111 ret = av_get_packet(s->pb, pkt, par->block_align);
112 pkt->duration = 1024;
113 return ret;
114 }
115
116 AVInputFormat ff_hca_demuxer = {
117 .name = "hca",
118 .long_name = NULL_IF_CONFIG_SMALL("CRI HCA"),
119 .read_probe = hca_probe,
120 .read_header = hca_read_header,
121 .read_packet = hca_read_packet,
122 .extensions = "hca",
123 .flags = AVFMT_GENERIC_INDEX,
124 };
125