FFmpeg
acm.c
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1 /*
2  * ACM demuxer
3  * Copyright (c) 2015 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 "rawdec.h"
25 #include "internal.h"
26 
27 static int acm_probe(const AVProbeData *p)
28 {
29  if (AV_RB32(p->buf) != 0x97280301)
30  return 0;
31 
32  return AVPROBE_SCORE_MAX / 3 * 2;
33 }
34 
36 {
37  AVStream *st;
38  int ret;
39 
40  st = avformat_new_stream(s, NULL);
41  if (!st)
42  return AVERROR(ENOMEM);
43 
46 
47  ret = ff_get_extradata(s, st->codecpar, s->pb, 14);
48  if (ret < 0)
49  return ret;
50 
51  st->codecpar->channels = AV_RL16(st->codecpar->extradata + 8);
52  st->codecpar->sample_rate = AV_RL16(st->codecpar->extradata + 10);
53  if (st->codecpar->channels <= 0 || st->codecpar->sample_rate <= 0)
54  return AVERROR_INVALIDDATA;
55  st->start_time = 0;
56  st->duration = AV_RL32(st->codecpar->extradata + 4) / st->codecpar->channels;
58  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
59 
60  return 0;
61 }
62 
64  .name = "acm",
65  .long_name = NULL_IF_CONFIG_SMALL("Interplay ACM"),
66  .read_probe = acm_probe,
67  .read_header = acm_read_header,
68  .read_packet = ff_raw_read_partial_packet,
70  .extensions = "acm",
71  .raw_codec_id = AV_CODEC_ID_INTERPLAY_ACM,
72  .priv_data_size = sizeof(FFRawDemuxerContext),
73  .priv_class = &ff_raw_demuxer_class,
74 };
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
AVFMT_NO_BYTE_SEEK
#define AVFMT_NO_BYTE_SEEK
Format does not allow seeking by bytes.
Definition: avformat.h:475
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4347
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
ff_get_extradata
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:3261
AV_CODEC_ID_INTERPLAY_ACM
@ AV_CODEC_ID_INTERPLAY_ACM
Definition: codec_id.h:500
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
AVStream::internal
AVStreamInternal * internal
An opaque field for libavformat internal usage.
Definition: avformat.h:1009
AVFMT_NOBINSEARCH
#define AVFMT_NOBINSEARCH
Format does not allow to fall back on binary search via read_timestamp.
Definition: avformat.h:473
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
FFRawDemuxerContext
Definition: rawdec.h:36
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:890
AVInputFormat
Definition: avformat.h:626
ff_raw_read_partial_packet
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawdec.c:34
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
acm_probe
static int acm_probe(const AVProbeData *p)
Definition: acm.c:27
ff_raw_demuxer_class
const AVClass ff_raw_demuxer_class
Definition: rawdec.c:140
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
NULL
#define NULL
Definition: coverity.c:32
rawdec.h
ff_acm_demuxer
const AVInputFormat ff_acm_demuxer
Definition: acm.c:63
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
avpriv_set_pts_info
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:4771
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:847
AVStreamInternal::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:384
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
AVFMT_NOGENSEARCH
#define AVFMT_NOGENSEARCH
Format does not allow to fall back on generic search.
Definition: avformat.h:474
AVSTREAM_PARSE_FULL_RAW
@ AVSTREAM_PARSE_FULL_RAW
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:772
acm_read_header
static int acm_read_header(AVFormatContext *s)
Definition: acm.c:35
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:880