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
30 #include "libavutil/rational.h"
40 FF_OPT_TYPE_BINARY, ///< offset must point to a pointer immediately followed by an int for the length
41 FF_OPT_TYPE_CONST=128,
47 typedef struct AVOption {
51 * short English help text
52 * @todo What about other languages?
57 * The offset relative to the context structure where the option
58 * value is stored. It should be 0 for named constants.
61 enum AVOptionType type;
64 * the default value for scalar options
67 double min; ///< minimum valid value for the option
68 double max; ///< maximum valid value for the option
71 #define AV_OPT_FLAG_ENCODING_PARAM 1 ///< a generic parameter which can be set by the user for muxing or encoding
72 #define AV_OPT_FLAG_DECODING_PARAM 2 ///< a generic parameter which can be set by the user for demuxing or decoding
73 #define AV_OPT_FLAG_METADATA 4 ///< some data extracted or inserted into the file like title, comment, ...
74 #define AV_OPT_FLAG_AUDIO_PARAM 8
75 #define AV_OPT_FLAG_VIDEO_PARAM 16
76 #define AV_OPT_FLAG_SUBTITLE_PARAM 32
77 //FIXME think about enc-audio, ... style flags
80 * The logical unit to which the option belongs. Non-constant
81 * options and corresponding named constants share the same
89 * Looks for an option in \p obj. Looks only for the options which
90 * have the flags set as specified in \p mask and \p flags (that is,
91 * for which it is the case that opt->flags & mask == flags).
93 * @param[in] obj a pointer to a struct whose first element is a
94 * pointer to an AVClass
95 * @param[in] name the name of the option to look for
96 * @param[in] unit the unit of the option to look for, or any if NULL
97 * @return a pointer to the option found, or NULL if no option
100 const AVOption *av_find_opt(void *obj, const char *name, const char *unit, int mask, int flags);
103 * @see av_set_string2()
105 attribute_deprecated const AVOption *av_set_string(void *obj, const char *name, const char *val);
108 * Sets the field of obj with the given name to value.
110 * @param[in] obj A struct whose first element is a pointer to an
112 * @param[in] name the name of the field to set
113 * @param[in] val The value to set. If the field is not of a string
114 * type, then the given string is parsed.
115 * SI postfixes and some named scalars are supported.
116 * If the field is of a numeric type, it has to be a numeric or named
117 * scalar. Behavior with more than one scalar and +- infix operators
119 * If the field is of a flags type, it has to be a sequence of numeric
120 * scalars or named flags separated by '+' or '-'. Prefixing a flag
121 * with '+' causes it to be set without affecting the other flags;
122 * similarly, '-' unsets a flag.
123 * @return a pointer to the AVOption corresponding to the field set or
124 * NULL if no matching AVOption exists, or if the value \p val is not
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
130 const AVOption *av_set_string2(void *obj, const char *name, const char *val, int alloc);
132 const AVOption *av_set_double(void *obj, const char *name, double n);
133 const AVOption *av_set_q(void *obj, const char *name, AVRational n);
134 const AVOption *av_set_int(void *obj, const char *name, int64_t n);
135 double av_get_double(void *obj, const char *name, const AVOption **o_out);
136 AVRational av_get_q(void *obj, const char *name, const AVOption **o_out);
137 int64_t av_get_int(void *obj, const char *name, const AVOption **o_out);
138 const char *av_get_string(void *obj, const char *name, const AVOption **o_out, char *buf, int buf_len);
139 const AVOption *av_next_option(void *obj, const AVOption *last);
140 int av_opt_show(void *obj, void *av_log_obj);
141 void av_opt_set_defaults(void *s);
142 void av_opt_set_defaults2(void *s, int mask, int flags);
144 #endif /* AVCODEC_OPT_H */