FFmpeg
enum_options.c
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1 /*
2  * Copyright (c) 2011 Anton Khirnov
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /*
22  * enumerate avoptions and format them in texinfo format
23  */
24 
25 #include <string.h>
26 
27 #include "libavformat/avformat.h"
28 #include "libavcodec/avcodec.h"
29 #include "libavutil/log.h"
30 #include "libavutil/opt.h"
31 
32 static void print_usage(void)
33 {
34  fprintf(stderr, "Usage: enum_options type\n"
35  "type: format codec\n");
36  exit(1);
37 }
38 
39 static void print_option(const AVClass *class, const AVOption *o)
40 {
41  printf("@item -%s @var{", o->name);
42  switch (o->type) {
43  case FF_OPT_TYPE_BINARY: printf("hexadecimal string"); break;
44  case FF_OPT_TYPE_STRING: printf("string"); break;
45  case FF_OPT_TYPE_INT:
46  case FF_OPT_TYPE_INT64: printf("integer"); break;
47  case FF_OPT_TYPE_FLOAT:
48  case FF_OPT_TYPE_DOUBLE: printf("float"); break;
49  case FF_OPT_TYPE_RATIONAL: printf("rational number"); break;
50  case FF_OPT_TYPE_FLAGS: printf("flags"); break;
51  default: printf("value"); break;
52  }
53  printf("} (@emph{");
54 
56  printf("input");
58  printf("/");
59  }
61  printf("output");
62 
63  printf("})\n");
64  if (o->help)
65  printf("%s\n", o->help);
66 
67  if (o->unit) {
68  const AVOption *u = NULL;
69  printf("\nPossible values:\n@table @samp\n");
70 
71  while ((u = av_next_option(&class, u)))
72  if (u->type == FF_OPT_TYPE_CONST && u->unit && !strcmp(u->unit, o->unit))
73  printf("@item %s\n%s\n", u->name, u->help ? u->help : "");
74  printf("@end table\n");
75  }
76 }
77 
78 static void show_opts(const AVClass *class)
79 {
80  const AVOption *o = NULL;
81 
82  printf("@table @option\n");
83  while ((o = av_next_option(&class, o)))
84  if (o->type != FF_OPT_TYPE_CONST)
85  print_option(class, o);
86  printf("@end table\n");
87 }
88 
89 static void show_format_opts(void)
90 {
91  const AVInputFormat *iformat = NULL;
92  const AVOutputFormat *oformat = NULL;
93  void *iformat_opaque = NULL;
94  void *oformat_opaque = NULL;
95 
96  printf("@section Generic format AVOptions\n");
98 
99  printf("@section Format-specific AVOptions\n");
100  while ((iformat = av_demuxer_iterate(&iformat_opaque))) {
101  if (!iformat->priv_class)
102  continue;
103  printf("@subsection %s AVOptions\n", iformat->priv_class->class_name);
104  show_opts(iformat->priv_class);
105  }
106  while ((oformat = av_muxer_iterate(&oformat_opaque))) {
107  if (!oformat->priv_class)
108  continue;
109  printf("@subsection %s AVOptions\n", oformat->priv_class->class_name);
110  show_opts(oformat->priv_class);
111  }
112 }
113 
114 static void show_codec_opts(void)
115 {
116  AVCodec *c = NULL;
117 
118  printf("@section Generic codec AVOptions\n");
120 
121  printf("@section Codec-specific AVOptions\n");
122  while ((c = av_codec_next(c))) {
123  if (!c->priv_class)
124  continue;
125  printf("@subsection %s AVOptions\n", c->priv_class->class_name);
126  show_opts(c->priv_class);
127  }
128 }
129 
130 int main(int argc, char **argv)
131 {
132  if (argc < 2)
133  print_usage();
134 
135  if (!strcmp(argv[1], "format"))
137  else if (!strcmp(argv[1], "codec"))
138  show_codec_opts();
139  else
140  print_usage();
141 
142  return 0;
143 }
#define NULL
Definition: coverity.c:32
AVOption.
Definition: opt.h:246
AVCodec * av_codec_next(const AVCodec *c)
If c is NULL, returns the first registered codec, if c is non-NULL, returns the next registered codec...
Definition: allcodecs.c:844
AVCodec.
Definition: avcodec.h:3492
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:294
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
const char * name
Definition: opt.h:247
static void print_option(const AVClass *class, const AVOption *o)
Definition: enum_options.c:39
const char * help
short English help text
Definition: opt.h:253
AVOptions.
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
static void show_format_opts(void)
Definition: enum_options.c:89
#define u(width, name, range_min, range_max)
Definition: cbs_h2645.c:252
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:679
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
Definition: options.c:170
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:276
const AVOutputFormat * av_muxer_iterate(void **opaque)
Iterate over all registered muxers.
Definition: allformats.c:507
int main(int argc, char **argv)
Definition: enum_options.c:130
static void show_opts(const AVClass *class)
Definition: enum_options.c:78
const char * unit
The logical unit to which the option belongs.
Definition: opt.h:301
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:533
const AVInputFormat * av_demuxer_iterate(void **opaque)
Iterate over all registered demuxers.
Definition: allformats.c:524
int flags
Definition: opt.h:275
static AVInputFormat * iformat
Definition: ffprobe.c:257
Libavcodec external API header.
Describe the class of an AVClass context structure.
Definition: log.h:67
const AVClass * priv_class
AVClass for the private context.
Definition: avcodec.h:3518
Main libavformat public API header.
static void show_codec_opts(void)
Definition: enum_options.c:114
enum AVOptionType type
Definition: opt.h:260
printf("static const uint8_t my_array[100] = {\n")
static void print_usage(void)
Definition: enum_options.c:32