FFmpeg
nistspheredec.c
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1 /*
2  * NIST Sphere demuxer
3  * Copyright (c) 2012 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/avstring.h"
23 #include "libavutil/intreadwrite.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include "pcm.h"
27 
28 static int nist_probe(const AVProbeData *p)
29 {
30  if (AV_RL64(p->buf) == AV_RL64("NIST_1A\x0a"))
31  return AVPROBE_SCORE_MAX;
32  return 0;
33 }
34 
36 {
37  char buffer[256], coding[32] = "pcm", format[32] = "01";
38  int bps = 0, be = 0;
39  int32_t header_size = -1;
40  AVStream *st;
41 
42  st = avformat_new_stream(s, NULL);
43  if (!st)
44  return AVERROR(ENOMEM);
45 
47 
48  ff_get_line(s->pb, buffer, sizeof(buffer));
49  ff_get_line(s->pb, buffer, sizeof(buffer));
50  sscanf(buffer, "%"SCNd32, &header_size);
51  if (header_size <= 0)
52  return AVERROR_INVALIDDATA;
53 
54  while (!avio_feof(s->pb)) {
55  ff_get_line(s->pb, buffer, sizeof(buffer));
56 
57  if (avio_tell(s->pb) >= header_size)
58  return AVERROR_INVALIDDATA;
59 
60  if (!memcmp(buffer, "end_head", 8)) {
63 
64  if (!av_strcasecmp(coding, "pcm")) {
67  0, be, 0xFFFF);
68  } else if (!av_strcasecmp(coding, "alaw")) {
70  } else if (!av_strcasecmp(coding, "ulaw") ||
71  !av_strcasecmp(coding, "mu-law")) {
73  } else if (!av_strncasecmp(coding, "pcm,embedded-shorten", 20)) {
75  if (ff_alloc_extradata(st->codecpar, 1))
76  st->codecpar->extradata[0] = 1;
77  } else {
78  avpriv_request_sample(s, "coding %s", coding);
79  }
80 
81  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
82 
84 
85  if (avio_tell(s->pb) > header_size)
86  return AVERROR_INVALIDDATA;
87 
88  avio_skip(s->pb, header_size - avio_tell(s->pb));
89 
90  return 0;
91  } else if (!memcmp(buffer, "channel_count", 13)) {
92  sscanf(buffer, "%*s %*s %u", &st->codecpar->channels);
93  if (st->codecpar->channels <= 0 || st->codecpar->channels > INT16_MAX)
94  return AVERROR_INVALIDDATA;
95  } else if (!memcmp(buffer, "sample_byte_format", 18)) {
96  sscanf(buffer, "%*s %*s %31s", format);
97 
98  if (!av_strcasecmp(format, "01")) {
99  be = 0;
100  } else if (!av_strcasecmp(format, "10")) {
101  be = 1;
102  } else if (!av_strcasecmp(format, "mu-law")) {
104  } else if (av_strcasecmp(format, "1")) {
105  avpriv_request_sample(s, "sample byte format %s", format);
106  return AVERROR_PATCHWELCOME;
107  }
108  } else if (!memcmp(buffer, "sample_coding", 13)) {
109  sscanf(buffer, "%*s %*s %31s", coding);
110  } else if (!memcmp(buffer, "sample_count", 12)) {
111  sscanf(buffer, "%*s %*s %"SCNd64, &st->duration);
112  } else if (!memcmp(buffer, "sample_n_bytes", 14)) {
113  sscanf(buffer, "%*s %*s %d", &bps);
114  if (bps > INT16_MAX/8U)
115  return AVERROR_INVALIDDATA;
116  } else if (!memcmp(buffer, "sample_rate", 11)) {
117  sscanf(buffer, "%*s %*s %d", &st->codecpar->sample_rate);
118  } else if (!memcmp(buffer, "sample_sig_bits", 15)) {
119  sscanf(buffer, "%*s %*s %d", &st->codecpar->bits_per_coded_sample);
120  if (st->codecpar->bits_per_coded_sample <= 0 || st->codecpar->bits_per_coded_sample > INT16_MAX)
121  return AVERROR_INVALIDDATA;
122  } else {
123  char key[32], value[32];
124  if (sscanf(buffer, "%31s %*s %31s", key, value) == 2) {
125  av_dict_set(&s->metadata, key, value, AV_DICT_APPEND);
126  } else {
127  av_log(s, AV_LOG_ERROR, "Failed to parse '%s' as metadata\n", buffer);
128  }
129  }
130  }
131 
132  return AVERROR_EOF;
133 }
134 
136  .name = "nistsphere",
137  .long_name = NULL_IF_CONFIG_SMALL("NIST SPeech HEader REsources"),
138  .read_probe = nist_probe,
139  .read_header = nist_read_header,
140  .read_packet = ff_pcm_read_packet,
141  .read_seek = ff_pcm_read_seek,
142  .extensions = "nist,sph",
143  .flags = AVFMT_GENERIC_INDEX,
144 };
be
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it be(in the first position) for now. Options ------- Then comes the options array. This is what will define the user accessible options. For example
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:3093
AVCodecParameters::extradata
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: codec_par.h:74
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:4374
pcm.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AV_RL64
uint64_t_TMPL AV_RL64
Definition: bytestream.h:91
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
av_strcasecmp
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:215
AV_DICT_APPEND
#define AV_DICT_APPEND
If the entry already exists, append to it.
Definition: dict.h:75
nist_read_header
static int nist_read_header(AVFormatContext *s)
Definition: nistspheredec.c:35
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
U
#define U(x)
Definition: vp56_arith.h:37
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:538
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:890
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:626
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_CODEC_ID_PCM_MULAW
@ AV_CODEC_ID_PCM_MULAW
Definition: codec_id.h:319
key
const char * key
Definition: hwcontext_opencl.c:168
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
AV_CODEC_ID_PCM_ALAW
@ AV_CODEC_ID_PCM_ALAW
Definition: codec_id.h:320
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
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
av_strncasecmp
int av_strncasecmp(const char *a, const char *b, size_t n)
Locale-independent case-insensitive compare.
Definition: avstring.c:225
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:116
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:4799
bps
unsigned bps
Definition: movenc.c:1595
ff_nistsphere_demuxer
const AVInputFormat ff_nistsphere_demuxer
Definition: nistspheredec.c:135
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:177
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
ff_get_line
int ff_get_line(AVIOContext *s, char *buf, int maxlen)
Read a whole line of text from AVIOContext.
Definition: aviobuf.c:772
ff_pcm_read_packet
int ff_pcm_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: pcm.c:29
AVStream
Stream structure.
Definition: avformat.h:847
ff_pcm_read_seek
int ff_pcm_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: pcm.c:56
avformat.h
buffer
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
Definition: filter_design.txt:49
nist_probe
static int nist_probe(const AVProbeData *p)
Definition: nistspheredec.c:28
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:327
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
format
fg outputs[0] format
Definition: ffmpeg_filter.c:175
int32_t
int32_t
Definition: audioconvert.c:56
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
avstring.h
AV_CODEC_ID_SHORTEN
@ AV_CODEC_ID_SHORTEN
Definition: codec_id.h:437
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:3264
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:354