FFmpeg: libavformat/ads.c Source File

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libavformat

ads.c

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1 /*

2 * ADS/SS2 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/channel_layout.h"

23 #include "avformat.h"

24 #include "internal.h"

26 static int ads_probe(AVProbeData *p)

27 {

28 if (memcmp(p->buf, "SShd", 4) ||

29 memcmp(p->buf+32, "SSbd", 4))

30 return 0;

32 return AVPROBE_SCORE_MAX / 3 * 2;

33 }

35 static int ads_read_header(AVFormatContext *s)

36 {

37 int align, codec, size;

38 AVStream *st;

40 st = avformat_new_stream(s, NULL);

41 if (!st)

42 return AVERROR(ENOMEM);

44 avio_skip(s->pb, 8);

45 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

46 codec = avio_rl32(s->pb);

47 st->codec->sample_rate = avio_rl32(s->pb);

48 if (st->codec->sample_rate <= 0)

49 return AVERROR_INVALIDDATA;

50 st->codec->channels = avio_rl32(s->pb);

51 if (st->codec->channels <= 0)

52 return AVERROR_INVALIDDATA;

53 align = avio_rl32(s->pb);

54 if (align <= 0 || align > INT_MAX / st->codec->channels)

55 return AVERROR_INVALIDDATA;

57 if (codec == 1)

58 st->codec->codec_id = AV_CODEC_ID_PCM_S16LE_PLANAR;

59 else

60 st->codec->codec_id = AV_CODEC_ID_ADPCM_PSX;

62 st->codec->block_align = st->codec->channels * align;

63 avio_skip(s->pb, 12);

64 size = avio_rl32(s->pb);

65 if (st->codec->codec_id == AV_CODEC_ID_ADPCM_PSX)

66 st->duration = (size - 0x40) / 16 / st->codec->channels * 28;

67 avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);

69 return 0;

70 }

72 static int ads_read_packet(AVFormatContext *s, AVPacket *pkt)

73 {

74 AVCodecContext *codec = s->streams[0]->codec;

75 int ret;

77 ret = av_get_packet(s->pb, pkt, codec->block_align);

78 pkt->stream_index = 0;

79 return ret;

80 }

82 AVInputFormat ff_ads_demuxer = {

83 .name = "ads",

84 .long_name = NULL_IF_CONFIG_SMALL("Sony PS2 ADS"),

85 .read_probe = ads_probe,

86 .read_header = ads_read_header,

87 .read_packet = ads_read_packet,

88 .extensions = "ads,ss2",

89 };

ff_ads_demuxer

AVInputFormat ff_ads_demuxer

Definition: ads.c:82

NULL

#define NULL

Definition: coverity.c:32

const char * s

Definition: avisynth_c.h:631

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:4149

avio_skip

int64_t avio_skip(AVIOContext *s, int64_t offset)

Skip given number of bytes forward.

Definition: aviobuf.c:282

AVInputFormat

Definition: avformat.h:656

pkt

static AVPacket pkt

Definition: demuxing_decoding.c:54

AVCodecContext::block_align

int block_align

number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...

Definition: avcodec.h:2324

ads_probe

static int ads_probe(AVProbeData *p)

Definition: ads.c:26

AVFormatContext

Format I/O context.

Definition: avformat.h:1314

avformat_new_stream

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

Add a new stream to a media file.

Definition: utils.c:3805

AVFormatContext::streams

AVStream ** streams

A list of all streams in the file.

Definition: avformat.h:1382

ads_read_header

static int ads_read_header(AVFormatContext *s)

Definition: ads.c:35

av_get_packet

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:252

size

ptrdiff_t size

Definition: opengl_enc.c:101

AV_CODEC_ID_PCM_S16LE_PLANAR

Definition: avcodec.h:340

avio_rl32

unsigned int avio_rl32(AVIOContext *s)

Definition: aviobuf.c:667

AVERROR

#define AVERROR(e)

Definition: error.h:43

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:176

AVMEDIA_TYPE_AUDIO

Definition: avutil.h:194

internal.h

AVStream::codec

AVCodecContext * codec

Codec context associated with this stream.

Definition: avformat.h:896

AVProbeData::buf

unsigned char * buf

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

Definition: avformat.h:462

channel_layout.h

audio channel layout utility functions

AVStream

Stream structure.

Definition: avformat.h:877

align

const AVS_VideoInfo int align

Definition: avisynth_c.h:658

AVCodecContext::codec_type

enum AVMediaType codec_type

Definition: avcodec.h:1540

AVCodecContext::codec_id

enum AVCodecID codec_id

Definition: avcodec.h:1549

AVCodecContext::sample_rate

int sample_rate

samples per second

Definition: avcodec.h:2287

AVFormatContext::pb

AVIOContext * pb

I/O context.

Definition: avformat.h:1356

AVCodecContext

main external API structure.

Definition: avcodec.h:1532

AVProbeData

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

Definition: avformat.h:460

AV_CODEC_ID_ADPCM_PSX

Definition: avcodec.h:399

AVStream::duration

int64_t duration

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

Definition: avformat.h:936

AVPROBE_SCORE_MAX

#define AVPROBE_SCORE_MAX

maximum score

Definition: avformat.h:472

avformat.h

Main libavformat public API header.

ads_read_packet

static int ads_read_packet(AVFormatContext *s, AVPacket *pkt)

Definition: ads.c:72

AVCodecContext::channels

int channels

number of audio channels

Definition: avcodec.h:2288

AVInputFormat::name

const char * name

A comma separated list of short names for the format.

Definition: avformat.h:661

AVPacket::stream_index

int stream_index

Definition: avcodec.h:1469

AVPacket

This structure stores compressed data.

Definition: avcodec.h:1444

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