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 
65  .name = "acm",
66  .long_name = NULL_IF_CONFIG_SMALL("Interplay ACM"),
67  .read_probe = acm_probe,
68  .read_header = acm_read_header,
69  .read_packet = ff_raw_read_partial_packet,
71  .extensions = "acm",
72  .raw_codec_id = AV_CODEC_ID_INTERPLAY_ACM,
73  .priv_data_size = sizeof(FFRawDemuxerContext),
74  .priv_class = &acm_demuxer_class,
75 };
#define NULL
Definition: coverity.c:32
#define AVFMT_NOBINSEARCH
Format does not allow to fall back on binary search via read_timestamp.
Definition: avformat.h:473
#define AVERROR_INVALIDDATA
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:4892
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3957
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
static int acm_read_header(AVFormatContext *s)
Definition: acm.c:35
Format I/O context.
Definition: avformat.h:1358
enum AVStreamParseType need_parsing
Definition: avformat.h:1099
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4465
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:87
full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...
Definition: avformat.h:804
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
Definition: rawdec.c:35
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3953
#define FF_RAW_DEMUXER_CLASS(name)
Definition: rawdec.h:55
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat ff_acm_demuxer
Definition: acm.c:64
Stream structure.
Definition: avformat.h:881
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:467
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
#define AVFMT_NOGENSEARCH
Format does not allow to fall back on generic search.
Definition: avformat.h:474
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
static int acm_probe(const AVProbeData *p)
Definition: acm.c:27
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:930
int sample_rate
Audio only.
Definition: avcodec.h:4067
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
Main libavformat public API header.
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:920
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:3312
#define AVFMT_NO_BYTE_SEEK
Format does not allow seeking by bytes.
Definition: avformat.h:475
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3971
int channels
Audio only.
Definition: avcodec.h:4063
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:1028
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87