FFmpeg  4.4.5
acedec.c
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1 /*
2  * ACE 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 "avformat.h"
24 #include "internal.h"
25 
26 static int ace_probe(const AVProbeData *p)
27 {
28  uint32_t asc;
29 
30  if (AV_RB32(p->buf) != MKBETAG('A','A','C',' '))
31  return 0;
32  if (p->buf_size < 0x44)
33  return 0;
34  asc = AV_RB32(p->buf + 0x40);
35  if (asc < 0x44 || asc > p->buf_size - 4)
36  return 0;
37  if (AV_RB32(p->buf + asc) != MKBETAG('A','S','C',' '))
38  return 0;
39 
40  return AVPROBE_SCORE_MAX / 2 + 1;
41 }
42 
44 {
45  AVIOContext *pb = s->pb;
46  AVCodecParameters *par;
47  int ret, codec, rate, nb_channels;
48  uint32_t asc_pos, size;
49  AVStream *st;
50 
51  avio_skip(pb, 0x40);
52  asc_pos = avio_rb32(pb);
53  if (asc_pos < 0x44)
54  return AVERROR_INVALIDDATA;
55  avio_skip(pb, asc_pos - 0x44);
56  if (avio_rb32(pb) != MKBETAG('A','S','C',' '))
57  return AVERROR_INVALIDDATA;
58  avio_skip(pb, 0xec);
59  codec = avio_rb32(pb);
60  nb_channels = avio_rb32(pb);
61  if (nb_channels <= 0 || nb_channels > 8)
62  return AVERROR_INVALIDDATA;
63  size = avio_rb32(pb);
64  if (size == 0)
65  return AVERROR_INVALIDDATA;
66  rate = avio_rb32(pb);
67  if (rate <= 0)
68  return AVERROR_INVALIDDATA;
69  avio_skip(pb, 16);
70 
71  st = avformat_new_stream(s, NULL);
72  if (!st)
73  return AVERROR(ENOMEM);
74  st->start_time = 0;
75  par = st->codecpar;
77  par->channels = nb_channels;
78  par->sample_rate = rate;
79  par->block_align = (codec == 4 ? 0x60 : codec == 5 ? 0x98 : 0xC0) * nb_channels;
80  st->duration = (size / par->block_align) * 1024LL;
82 
83  ret = ff_alloc_extradata(par, 14);
84  if (ret < 0)
85  return ret;
86 
87  AV_WL16(st->codecpar->extradata, 1);
88  AV_WL16(st->codecpar->extradata+2, 2048 * par->channels);
89  AV_WL16(st->codecpar->extradata+4, 0);
90  AV_WL16(st->codecpar->extradata+6, codec == 4 ? 1 : 0);
91  AV_WL16(st->codecpar->extradata+8, codec == 4 ? 1 : 0);
92  AV_WL16(st->codecpar->extradata+10, 1);
93  AV_WL16(st->codecpar->extradata+12, 0);
94 
95  avpriv_set_pts_info(st, 64, 1, par->sample_rate);
96 
97  return 0;
98 }
99 
101 {
102  AVCodecParameters *par = s->streams[0]->codecpar;
103 
104  return av_get_packet(s->pb, pkt, par->block_align);
105 }
106 
108  .name = "ace",
109  .long_name = NULL_IF_CONFIG_SMALL("tri-Ace Audio Container"),
110  .read_probe = ace_probe,
111  .read_header = ace_read_header,
112  .read_packet = ace_read_packet,
113  .flags = AVFMT_GENERIC_INDEX,
114 };
AVInputFormat ff_ace_demuxer
Definition: acedec.c:107
static int ace_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: acedec.c:100
static int ace_read_header(AVFormatContext *s)
Definition: acedec.c:43
static int ace_probe(const AVProbeData *p)
Definition: acedec.c:26
Main libavformat public API header.
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:310
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
#define AV_RB32
Definition: intreadwrite.h:130
#define s(width, name)
Definition: cbs_vp9.c:257
int nb_channels
#define MKBETAG(a, b, c, d)
Definition: common.h:479
#define NULL
Definition: coverity.c:32
@ AV_CODEC_ID_ATRAC3
Definition: codec_id.h:455
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
#define AV_WL16(p, v)
Definition: intreadwrite.h:412
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4945
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0.
Definition: utils.c:3314
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
int channels
Audio only.
Definition: codec_par.h:166
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int block_align
Audio only.
Definition: codec_par.h:177
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:922
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:912
AVPacket * pkt
Definition: movenc.c:59
int size