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 {
92  AVOutputFormat *oformat = NULL;
93 
94  printf("@section Generic format AVOptions\n");
96 
97  printf("@section Format-specific AVOptions\n");
98  while ((iformat = av_iformat_next(iformat))) {
99  if (!iformat->priv_class)
100  continue;
101  printf("@subsection %s AVOptions\n", iformat->priv_class->class_name);
102  show_opts(iformat->priv_class);
103  }
104  while ((oformat = av_oformat_next(oformat))) {
105  if (!oformat->priv_class)
106  continue;
107  printf("@subsection %s AVOptions\n", oformat->priv_class->class_name);
108  show_opts(oformat->priv_class);
109  }
110 }
111 
112 static void show_codec_opts(void)
113 {
114  AVCodec *c = NULL;
115 
116  printf("@section Generic codec AVOptions\n");
118 
119  printf("@section Codec-specific AVOptions\n");
120  while ((c = av_codec_next(c))) {
121  if (!c->priv_class)
122  continue;
123  printf("@subsection %s AVOptions\n", c->priv_class->class_name);
124  show_opts(c->priv_class);
125  }
126 }
127 
128 int main(int argc, char **argv)
129 {
130  if (argc < 2)
131  print_usage();
132 
133  if (!strcmp(argv[1], "format"))
135  else if (!strcmp(argv[1], "codec"))
136  show_codec_opts();
137  else
138  print_usage();
139 
140  return 0;
141 }
#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:840
AVCodec.
Definition: avcodec.h:3481
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:168
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:276
int main(int argc, char **argv)
Definition: enum_options.c:128
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:300
const AVClass * priv_class
AVClass for the private context.
Definition: avformat.h:533
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:3507
Main libavformat public API header.
static void show_codec_opts(void)
Definition: enum_options.c:112
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