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1 /*
2  * HCOM demuxer
3  * Copyright (c) 2019 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
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  */
22 #include "libavutil/intreadwrite.h"
23 #include "libavcodec/internal.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "pcm.h"
28 static int hcom_probe(const AVProbeData *p)
29 {
30  if (p->buf_size < 132)
31  return 0;
32  if (!memcmp(p->buf+65, "FSSD", 4) &&
33  !memcmp(p->buf+128, "HCOM", 4))
35  return 0;
36 }
39 {
40  AVStream *st;
41  av_unused unsigned data_size, rsrc_size, huffcount;
42  unsigned compresstype, divisor;
43  unsigned dict_entries;
44  int ret;
46  avio_skip(s->pb, 83);
47  data_size = avio_rb32(s->pb);
48  rsrc_size = avio_rb32(s->pb);
49  avio_skip(s->pb, 128-91+4);
50  huffcount = avio_rb32(s->pb);
51  avio_skip(s->pb, 4);
52  compresstype = avio_rb32(s->pb);
53  if (compresstype > 1)
55  divisor = avio_rb32(s->pb);
56  if (divisor == 0 || divisor > 4)
58  dict_entries = avio_rb16(s->pb);
60  st = avformat_new_stream(s, NULL);
61  if (!st)
62  return AVERROR(ENOMEM);
65  st->codecpar->channels = 1;
66  st->codecpar->sample_rate = 22050 / divisor;
69  st->codecpar->block_align = 4;
71  ret = ff_alloc_extradata(st->codecpar, dict_entries * 4 + 7);
72  if (ret < 0)
73  return ret;
74  AV_WB16(st->codecpar->extradata, dict_entries);
75  AV_WB32(st->codecpar->extradata + 2, compresstype);
76  avio_read(s->pb, st->codecpar->extradata + 6, dict_entries * 4);
77  avio_skip(s->pb, 1);
78  st->codecpar->extradata[dict_entries * 4 + 6] = avio_r8(s->pb);
80  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
82  return 0;
83 }
86  .name = "hcom",
87  .long_name = NULL_IF_CONFIG_SMALL("Macintosh HCOM"),
88  .read_probe = hcom_probe,
89  .read_header = hcom_read_header,
90  .read_packet = ff_pcm_read_packet,
91 };
#define NULL
Definition: coverity.c:32
Invalid data found when processing input.
Definition: error.h:59
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:4999
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:766
Format I/O context.
Definition: avformat.h:1247
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4553
#define AV_WB16(p, v)
Definition: intreadwrite.h:405
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:117
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
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
int block_align
Audio only.
Definition: codec_par.h:177
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:3368
static int hcom_read_header(AVFormatContext *s)
Definition: hcom.c:38
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:884
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
AVIOContext * pb
I/O context.
Definition: avformat.h:1289
static int hcom_probe(const AVProbeData *p)
Definition: hcom.c:28
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
int sample_rate
Audio only.
Definition: codec_par.h:170
maximum score
Definition: avformat.h:453
Main libavformat public API header.
common internal api header.
AVInputFormat ff_hcom_demuxer
Definition: hcom.c:85
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
int channels
Audio only.
Definition: codec_par.h:166
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1049
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
#define av_unused
Definition: attributes.h:131