FFmpeg: libavformat/pvfdec.c Source File

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libavformat

pvfdec.c

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1 /*

2 * PVF 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 "libavcodec/internal.h"

23 #include "avformat.h"

24 #include "internal.h"

25 #include "pcm.h"

27 static int pvf_probe(AVProbeData *p)

28 {

29 if (!memcmp(p->buf, "PVF1\n", 5))

30 return AVPROBE_SCORE_MAX;

31 return 0;

32 }

34 static int pvf_read_header(AVFormatContext *s)

35 {

36 char buffer[32];

37 AVStream *st;

38 int bps, channels, sample_rate;

40 avio_skip(s->pb, 5);

41 ff_get_line(s->pb, buffer, sizeof(buffer));

42 if (sscanf(buffer, "%d %d %d",

43 &channels,

44 &sample_rate,

45 &bps) != 3)

46 return AVERROR_INVALIDDATA;

48 if (channels <= 0 || channels > FF_SANE_NB_CHANNELS ||

49 bps <= 0 || bps > INT_MAX / FF_SANE_NB_CHANNELS || sample_rate <= 0)

50 return AVERROR_INVALIDDATA;

52 st = avformat_new_stream(s, NULL);

53 if (!st)

54 return AVERROR(ENOMEM);

56 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;

57 st->codecpar->channels = channels;

58 st->codecpar->sample_rate = sample_rate;

59 st->codecpar->codec_id = ff_get_pcm_codec_id(bps, 0, 1, 0xFFFF);

60 st->codecpar->bits_per_coded_sample = bps;

61 st->codecpar->block_align = bps * st->codecpar->channels / 8;

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

65 return 0;

66 }

68 AVInputFormat ff_pvf_demuxer = {

69 .name = "pvf",

70 .long_name = NULL_IF_CONFIG_SMALL("PVF (Portable Voice Format)"),

71 .read_probe = pvf_probe,

72 .read_header = pvf_read_header,

73 .read_packet = ff_pcm_read_packet,

74 .read_seek = ff_pcm_read_seek,

75 .extensions = "pvf",

76 .flags = AVFMT_GENERIC_INDEX,

77 };

FF_SANE_NB_CHANNELS

#define FF_SANE_NB_CHANNELS

Definition: internal.h:86

NULL

#define NULL

Definition: coverity.c:32

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

channels

Definition: aptx.c:30

AVCodecParameters::codec_id

enum AVCodecID codec_id

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

Definition: avcodec.h:3884

avio_skip

int64_t avio_skip(AVIOContext *s, int64_t offset)

Skip given number of bytes forward.

Definition: aviobuf.c:331

AVInputFormat

Definition: avformat.h:642

pvf_read_header

static int pvf_read_header(AVFormatContext *s)

Definition: pvfdec.c:34

AVFormatContext

Format I/O context.

Definition: avformat.h:1342

pcm.h

avformat_new_stream

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

Add a new stream to a media file.

Definition: utils.c:4450

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: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

pvf_probe

static int pvf_probe(AVProbeData *p)

Definition: pvfdec.c:27

AVProbeData::buf

unsigned char * buf

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

Definition: avformat.h:450

AVCodecParameters::block_align

int block_align

Audio only.

Definition: avcodec.h:4001

ff_get_line

int ff_get_line(AVIOContext *s, char *buf, int maxlen)

Read a whole line of text from AVIOContext.

Definition: aviobuf.c:809

ff_pcm_read_seek

int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)

Definition: pcm.c:52

AVStream

Stream structure.

Definition: avformat.h:873

ff_pcm_read_packet

int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)

Definition: pcm.c:29

ff_pvf_demuxer

AVInputFormat ff_pvf_demuxer

Definition: pvfdec.c:68

sample_rate

Definition: ffmpeg_filter.c:190

AVFormatContext::pb

AVIOContext * pb

I/O context.

Definition: avformat.h:1384

AVFMT_GENERIC_INDEX

#define AVFMT_GENERIC_INDEX

Use generic index building code.

Definition: avformat.h:470

ff_get_pcm_codec_id

enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags)

Select a PCM codec based on the given parameters.

Definition: utils.c:3129

AVProbeData

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

Definition: avformat.h:448

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.

internal.h

common internal api header.

bps

unsigned bps

Definition: movenc.c:1456

AVCodecParameters::bits_per_coded_sample

int bits_per_coded_sample

The number of bits per sample in the codedwords.

Definition: avcodec.h:3926

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

buffer

GLuint buffer

Definition: opengl_enc.c:102

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