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
70 /* TODO those are unused now */
74 double min; ///< minimum valid value for the option
75 double max; ///< maximum valid value for the option
78 #define AV_OPT_FLAG_ENCODING_PARAM 1 ///< a generic parameter which can be set by the user for muxing or encoding
79 #define AV_OPT_FLAG_DECODING_PARAM 2 ///< a generic parameter which can be set by the user for demuxing or decoding
80 #define AV_OPT_FLAG_METADATA 4 ///< some data extracted or inserted into the file like title, comment, ...
81 #define AV_OPT_FLAG_AUDIO_PARAM 8
82 #define AV_OPT_FLAG_VIDEO_PARAM 16
83 #define AV_OPT_FLAG_SUBTITLE_PARAM 32
84 //FIXME think about enc-audio, ... style flags
87 * The logical unit to which the option belongs. Non-constant
88 * options and corresponding named constants share the same
95 * Look for an option in obj. Look only for the options which
96 * have the flags set as specified in mask and flags (that is,
97 * for which it is the case that opt->flags & mask == flags).
99 * @param[in] obj a pointer to a struct whose first element is a
100 * pointer to an AVClass
101 * @param[in] name the name of the option to look for
102 * @param[in] unit the unit of the option to look for, or any if NULL
103 * @return a pointer to the option found, or NULL if no option
106 const AVOption *av_find_opt(void *obj, const char *name, const char *unit, int mask, int flags);
109 * Set the field of obj with the given name to value.
111 * @param[in] obj A struct whose first element is a pointer to an
113 * @param[in] name the name of the field to set
114 * @param[in] val The value to set. If the field is not of a string
115 * type, then the given string is parsed.
116 * SI postfixes and some named scalars are supported.
117 * If the field is of a numeric type, it has to be a numeric or named
118 * scalar. Behavior with more than one scalar and +- infix operators
120 * If the field is of a flags type, it has to be a sequence of numeric
121 * scalars or named flags separated by '+' or '-'. Prefixing a flag
122 * with '+' causes it to be set without affecting the other flags;
123 * similarly, '-' unsets a flag.
124 * @param[out] o_out if non-NULL put here a pointer to the AVOption
126 * @param alloc when 1 then the old value will be av_freed() and the
128 * when 0 then no av_free() nor av_strdup() will be used
129 * @return 0 if the value has been set, or an AVERROR code in case of
131 * AVERROR(ENOENT) if no matching option exists
132 * AVERROR(ERANGE) if the value is out of range
133 * AVERROR(EINVAL) if the value is not valid
135 int av_set_string3(void *obj, const char *name, const char *val, int alloc, const AVOption **o_out);
137 const AVOption *av_set_double(void *obj, const char *name, double n);
138 const AVOption *av_set_q(void *obj, const char *name, AVRational n);
139 const AVOption *av_set_int(void *obj, const char *name, int64_t n);
140 double av_get_double(void *obj, const char *name, const AVOption **o_out);
141 AVRational av_get_q(void *obj, const char *name, const AVOption **o_out);
142 int64_t av_get_int(void *obj, const char *name, const AVOption **o_out);
143 const char *av_get_string(void *obj, const char *name, const AVOption **o_out, char *buf, int buf_len);
144 const AVOption *av_next_option(void *obj, const AVOption *last);
147 * Show the obj options.
149 * @param req_flags requested flags for the options to show. Show only the
150 * options for which it is opt->flags & req_flags.
151 * @param rej_flags rejected flags for the options to show. Show only the
152 * options for which it is !(opt->flags & req_flags).
153 * @param av_log_obj log context to use for showing the options
155 int av_opt_show2(void *obj, void *av_log_obj, int req_flags, int rej_flags);
157 void av_opt_set_defaults(void *s);
158 void av_opt_set_defaults2(void *s, int mask, int flags);
161 * Parse the key/value pairs list in opts. For each key/value pair
162 * found, stores the value in the field in ctx that is named like the
163 * key. ctx must be an AVClass context, storing is done using
166 * @param key_val_sep a 0-terminated list of characters used to
167 * separate key from value
168 * @param pairs_sep a 0-terminated list of characters used to separate
169 * two pairs from each other
170 * @return the number of successfully set key/value pairs, or a negative
171 * value corresponding to an AVERROR code in case of error:
172 * AVERROR(EINVAL) if opts cannot be parsed,
173 * the error code issued by av_set_string3() if a key/value pair
176 int av_set_options_string(void *ctx, const char *opts,
177 const char *key_val_sep, const char *pairs_sep);
179 #endif /* AVUTIL_OPT_H */