3 * copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
5 * This file is part of FFmpeg.
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.
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.
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
41 FF_OPT_TYPE_BINARY, ///< offset must point to a pointer immediately followed by an int for the length
42 FF_OPT_TYPE_CONST=128,
48 typedef struct AVOption {
52 * short English help text
53 * @todo What about other languages?
58 * The offset relative to the context structure where the option
59 * value is stored. It should be 0 for named constants.
62 enum AVOptionType type;
65 * the default value for scalar options
71 double min; ///< minimum valid value for the option
72 double max; ///< maximum valid value for the option
75 #define AV_OPT_FLAG_ENCODING_PARAM 1 ///< a generic parameter which can be set by the user for muxing or encoding
76 #define AV_OPT_FLAG_DECODING_PARAM 2 ///< a generic parameter which can be set by the user for demuxing or decoding
77 #define AV_OPT_FLAG_METADATA 4 ///< some data extracted or inserted into the file like title, comment, ...
78 #define AV_OPT_FLAG_AUDIO_PARAM 8
79 #define AV_OPT_FLAG_VIDEO_PARAM 16
80 #define AV_OPT_FLAG_SUBTITLE_PARAM 32
81 //FIXME think about enc-audio, ... style flags
84 * The logical unit to which the option belongs. Non-constant
85 * options and corresponding named constants share the same
92 * Look for an option in obj. Look only for the options which
93 * have the flags set as specified in mask and flags (that is,
94 * for which it is the case that opt->flags & mask == flags).
96 * @param[in] obj a pointer to a struct whose first element is a
97 * pointer to an AVClass
98 * @param[in] name the name of the option to look for
99 * @param[in] unit the unit of the option to look for, or any if NULL
100 * @return a pointer to the option found, or NULL if no option
103 const AVOption *av_find_opt(void *obj, const char *name, const char *unit, int mask, int flags);
106 * Set the field of obj with the given name to value.
108 * @param[in] obj A struct whose first element is a pointer to an
110 * @param[in] name the name of the field to set
111 * @param[in] val The value to set. If the field is not of a string
112 * type, then the given string is parsed.
113 * SI postfixes and some named scalars are supported.
114 * If the field is of a numeric type, it has to be a numeric or named
115 * scalar. Behavior with more than one scalar and +- infix operators
117 * If the field is of a flags type, it has to be a sequence of numeric
118 * scalars or named flags separated by '+' or '-'. Prefixing a flag
119 * with '+' causes it to be set without affecting the other flags;
120 * similarly, '-' unsets a flag.
121 * @param[out] o_out if non-NULL put here a pointer to the AVOption
123 * @param alloc when 1 then the old value will be av_freed() and the
125 * when 0 then no av_free() nor av_strdup() will be used
126 * @return 0 if the value has been set, or an AVERROR code in case of
128 * AVERROR(ENOENT) if no matching option exists
129 * AVERROR(ERANGE) if the value is out of range
130 * AVERROR(EINVAL) if the value is not valid
132 int av_set_string3(void *obj, const char *name, const char *val, int alloc, const AVOption **o_out);
134 const AVOption *av_set_double(void *obj, const char *name, double n);
135 const AVOption *av_set_q(void *obj, const char *name, AVRational n);
136 const AVOption *av_set_int(void *obj, const char *name, int64_t n);
137 double av_get_double(void *obj, const char *name, const AVOption **o_out);
138 AVRational av_get_q(void *obj, const char *name, const AVOption **o_out);
139 int64_t av_get_int(void *obj, const char *name, const AVOption **o_out);
140 const char *av_get_string(void *obj, const char *name, const AVOption **o_out, char *buf, int buf_len);
141 const AVOption *av_next_option(void *obj, const AVOption *last);
144 * Show the obj options.
146 * @param req_flags requested flags for the options to show. Show only the
147 * options for which it is opt->flags & req_flags.
148 * @param rej_flags rejected flags for the options to show. Show only the
149 * options for which it is !(opt->flags & req_flags).
150 * @param av_log_obj log context to use for showing the options
152 int av_opt_show2(void *obj, void *av_log_obj, int req_flags, int rej_flags);
154 void av_opt_set_defaults(void *s);
155 void av_opt_set_defaults2(void *s, int mask, int flags);
158 * Parse the key/value pairs list in opts. For each key/value pair
159 * found, stores the value in the field in ctx that is named like the
160 * key. ctx must be an AVClass context, storing is done using
163 * @param key_val_sep a 0-terminated list of characters used to
164 * separate key from value
165 * @param pairs_sep a 0-terminated list of characters used to separate
166 * two pairs from each other
167 * @return the number of successfully set key/value pairs, or a negative
168 * value corresponding to an AVERROR code in case of error:
169 * AVERROR(EINVAL) if opts cannot be parsed,
170 * the error code issued by av_set_string3() if a key/value pair
173 int av_set_options_string(void *ctx, const char *opts,
174 const char *key_val_sep, const char *pairs_sep);
176 #endif /* AVUTIL_OPT_H */