FFmpeg: libavformat/acm.c Source File

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libavformat

acm.c

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1 /*

2 * ACM demuxer

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 */

22 #include "libavutil/intreadwrite.h"

23 #include "avformat.h"

24 #include "rawdec.h"

25 #include "internal.h"

27 static int acm_probe(AVProbeData *p)

28 {

29 if (AV_RB32(p->buf) != 0x97280301)

30 return 0;

32 return AVPROBE_SCORE_MAX / 3 * 2;

33 }

35 static int acm_read_header(AVFormatContext *s)

36 {

37 AVStream *st;

38 int ret;

40 st = avformat_new_stream(s, NULL);

41 if (!st)

42 return AVERROR(ENOMEM);

44 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;

45 st->codecpar->codec_id = AV_CODEC_ID_INTERPLAY_ACM;

47 ff_alloc_extradata(st->codecpar, 14);

48 if (!st->codecpar->extradata)

49 return AVERROR(ENOMEM);

50 ret = avio_read(s->pb, st->codecpar->extradata, 14);

51 if (ret < 10)

52 return ret < 0 ? ret : AVERROR_EOF;

54 st->codecpar->channels = AV_RL16(st->codecpar->extradata + 8);

55 st->codecpar->sample_rate = AV_RL16(st->codecpar->extradata + 10);

56 if (st->codecpar->channels <= 0 || st->codecpar->sample_rate <= 0)

57 return AVERROR_INVALIDDATA;

58 st->start_time = 0;

59 st->duration = AV_RL32(st->codecpar->extradata + 4) / st->codecpar->channels;

60 st->need_parsing = AVSTREAM_PARSE_FULL_RAW;

61 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);

63 return 0;

64 }

66 AVInputFormat ff_acm_demuxer = {

67 .name = "acm",

68 .long_name = NULL_IF_CONFIG_SMALL("Interplay ACM"),

69 .read_probe = acm_probe,

70 .read_header = acm_read_header,

71 .read_packet = ff_raw_read_partial_packet,

72 .flags = AVFMT_NOBINSEARCH | AVFMT_NOGENSEARCH | AVFMT_NO_BYTE_SEEK | AVFMT_NOTIMESTAMPS,

73 .extensions = "acm",

74 .raw_codec_id = AV_CODEC_ID_INTERPLAY_ACM,

75 };

NULL

#define NULL

Definition: coverity.c:32

AVFMT_NOBINSEARCH

#define AVFMT_NOBINSEARCH

Format does not allow to fall back on binary search via read_timestamp.

Definition: avformat.h:475

const char * s

Definition: avisynth_c.h:768

AVERROR_INVALIDDATA

#define AVERROR_INVALIDDATA

Invalid data found when processing input.

Definition: error.h:59

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:4820

AVCodecParameters::codec_id

enum AVCodecID codec_id

Specific type of the encoded data (the codec used).

Definition: avcodec.h:3884

AVInputFormat

Definition: avformat.h:642

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:87

acm_read_header

static int acm_read_header(AVFormatContext *s)

Definition: acm.c:35

AVFormatContext

Format I/O context.

Definition: avformat.h:1342

AVStream::need_parsing

enum AVStreamParseType need_parsing

Definition: avformat.h:1091

avformat_new_stream

AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)

Add a new stream to a media file.

Definition: utils.c:4450

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:87

AV_CODEC_ID_INTERPLAY_ACM

Definition: avcodec.h:630

AVERROR_EOF

#define AVERROR_EOF

End of file.

Definition: error.h:55

acm_probe

static int acm_probe(AVProbeData *p)

Definition: acm.c:27

AVSTREAM_PARSE_FULL_RAW

full parsing and repack with timestamp and position generation by parser for raw this assumes that ea...

Definition: avformat.h:797

avio_read

int avio_read(AVIOContext *s, unsigned char *buf, int size)

Read size bytes from AVIOContext into buf.

Definition: aviobuf.c:648

AVERROR

#define AVERROR(e)

Definition: error.h:43

ff_raw_read_partial_packet

int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)

Definition: rawdec.c:35

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:186

AVCodecParameters::codec_type

enum AVMediaType codec_type

General type of the encoded data.

Definition: avcodec.h:3880

AVMEDIA_TYPE_AUDIO

Definition: avutil.h:202

internal.h

AVProbeData::buf

unsigned char * buf

Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.

Definition: avformat.h:450

ff_alloc_extradata

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:3280

intreadwrite.h

ff_acm_demuxer

AVInputFormat ff_acm_demuxer

Definition: acm.c:66

AVStream

Stream structure.

Definition: avformat.h:873

AVFMT_NOTIMESTAMPS

#define AVFMT_NOTIMESTAMPS

Format does not need / have any timestamps.

Definition: avformat.h:469

AVFormatContext::pb

AVIOContext * pb

I/O context.

Definition: avformat.h:1384

AVFMT_NOGENSEARCH

#define AVFMT_NOGENSEARCH

Format does not allow to fall back on generic search.

Definition: avformat.h:476

AVProbeData

This structure contains the data a format has to probe a file.

Definition: avformat.h:448

AVStream::duration

int64_t duration

Decoding: duration of the stream, in stream time base.

Definition: avformat.h:922

AVCodecParameters::sample_rate

int sample_rate

Audio only.

Definition: avcodec.h:3994

AVPROBE_SCORE_MAX

#define AVPROBE_SCORE_MAX

maximum score

Definition: avformat.h:460

avformat.h

Main libavformat public API header.

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:912

rawdec.h

AVFMT_NO_BYTE_SEEK

#define AVFMT_NO_BYTE_SEEK

Format does not allow seeking by bytes.

Definition: avformat.h:477

AVCodecParameters::extradata

uint8_t * extradata

Extra binary data needed for initializing the decoder, codec-dependent.

Definition: avcodec.h:3898

AVCodecParameters::channels

int channels

Audio only.

Definition: avcodec.h:3990

AVInputFormat::name

const char * name

A comma separated list of short names for the format.

Definition: avformat.h:647

AVStream::codecpar

AVCodecParameters * codecpar

Codec parameters associated with this stream.

Definition: avformat.h:1020

AV_RL32

uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32

Definition: bytestream.h:87

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