FFmpeg
enum_options.c
Go to the documentation of this file.
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  void *iter = NULL;
117  AVCodec *c = NULL;
118 
119  printf("@section Generic codec AVOptions\n");
121 
122  printf("@section Codec-specific AVOptions\n");
123  while ((c = av_codec_iterate(&iter))) {
124  if (!c->priv_class)
125  continue;
126  printf("@subsection %s AVOptions\n", c->priv_class->class_name);
127  show_opts(c->priv_class);
128  }
129 }
130 
131 int main(int argc, char **argv)
132 {
133  if (argc < 2)
134  print_usage();
135 
136  if (!strcmp(argv[1], "format"))
138  else if (!strcmp(argv[1], "codec"))
139  show_codec_opts();
140  else
141  print_usage();
142 
143  return 0;
144 }
#define NULL
Definition: coverity.c:32
AVOption.
Definition: opt.h:248
const AVCodec * av_codec_iterate(void **opaque)
Iterate over all registered codecs.
Definition: allcodecs.c:849
AVCodec.
Definition: codec.h:190
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:310
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:249
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:255
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:262
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:677
const AVClass * avformat_get_class(void)
Get the AVClass for AVFormatContext.
Definition: options.c:237
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:278
const AVOutputFormat * av_muxer_iterate(void **opaque)
Iterate over all registered muxers.
Definition: allformats.c:533
int main(int argc, char **argv)
Definition: enum_options.c:131
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:304
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:528
const AVInputFormat * av_demuxer_iterate(void **opaque)
Iterate over all registered demuxers.
Definition: allformats.c:550
int flags
Definition: opt.h:277
static AVInputFormat * iformat
Definition: ffprobe.c:259
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: codec.h:216
Main libavformat public API header.
static void show_codec_opts(void)
Definition: enum_options.c:114
enum AVOptionType type
Definition: opt.h:262
printf("static const uint8_t my_array[100] = {\n")
static void print_usage(void)
Definition: enum_options.c:32