/* * AVOptions * copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at> * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVCODEC_OPT_H #define AVCODEC_OPT_H /** * @file opt.h * AVOptions */ #include "libavutil/rational.h" enum AVOptionType{ FF_OPT_TYPE_FLAGS, FF_OPT_TYPE_INT, FF_OPT_TYPE_INT64, FF_OPT_TYPE_DOUBLE, FF_OPT_TYPE_FLOAT, FF_OPT_TYPE_STRING, FF_OPT_TYPE_RATIONAL, FF_OPT_TYPE_BINARY, ///< offset must point to a pointer immediately followed by an int for the length FF_OPT_TYPE_CONST=128, }; /** * AVOption */ typedef struct AVOption { const char *name; /** * short English help text * @todo What about other languages? */ const char *help; /** * The offset relative to the context structure where the option * value is stored. It should be 0 for named constants. */ int offset; enum AVOptionType type; /** * the default value for scalar options */ double default_val; double min; ///< minimum valid value for the option double max; ///< maximum valid value for the option int flags; #define AV_OPT_FLAG_ENCODING_PARAM 1 ///< a generic parameter which can be set by the user for muxing or encoding #define AV_OPT_FLAG_DECODING_PARAM 2 ///< a generic parameter which can be set by the user for demuxing or decoding #define AV_OPT_FLAG_METADATA 4 ///< some data extracted or inserted into the file like title, comment, ... #define AV_OPT_FLAG_AUDIO_PARAM 8 #define AV_OPT_FLAG_VIDEO_PARAM 16 #define AV_OPT_FLAG_SUBTITLE_PARAM 32 //FIXME think about enc-audio, ... style flags /** * The logical unit to which the option belongs. Non-constant * options and corresponding named constants share the same * unit. May be NULL. */ const char *unit; } AVOption; /** * Looks for an option in \p obj. Looks only for the options which * have the flags set as specified in \p mask and \p flags (that is, * for which it is the case that opt->flags & mask == flags). * * @param[in] obj a pointer to a struct whose first element is a * pointer to an #AVClass * @param[in] name the name of the option to look for * @param[in] unit the unit of the option to look for, or any if NULL * @return a pointer to the option found, or NULL if no option * has been found */ const AVOption *av_find_opt(void *obj, const char *name, const char *unit, int mask, int flags); /** * @see av_set_string2() */ attribute_deprecated const AVOption *av_set_string(void *obj, const char *name, const char *val); /** * Sets the field of obj with the given name to value. * * @param[in] obj A struct whose first element is a pointer to an * AVClass. * @param[in] name the name of the field to set * @param[in] val The value to set. If the field is not of a string * type, then the given string is parsed. * SI postfixes and some named scalars are supported. * If the field is of a numeric type, it has to be a numeric or named * scalar. Behavior with more than one scalar and +- infix operators * is undefined. * If the field is of a flags type, it has to be a sequence of numeric * scalars or named flags separated by '+' or '-'. Prefixing a flag * with '+' causes it to be set without affecting the other flags; * similarly, '-' unsets a flag. * @return a pointer to the AVOption corresponding to the field set or * NULL if no matching AVOption exists, or if the value \p val is not * valid * @param alloc when 1 then the old value will be av_freed() and the * new av_strduped() * when 0 then no av_free() nor av_strdup() will be used */ const AVOption *av_set_string2(void *obj, const char *name, const char *val, int alloc); const AVOption *av_set_double(void *obj, const char *name, double n); const AVOption *av_set_q(void *obj, const char *name, AVRational n); const AVOption *av_set_int(void *obj, const char *name, int64_t n); double av_get_double(void *obj, const char *name, const AVOption **o_out); AVRational av_get_q(void *obj, const char *name, const AVOption **o_out); int64_t av_get_int(void *obj, const char *name, const AVOption **o_out); const char *av_get_string(void *obj, const char *name, const AVOption **o_out, char *buf, int buf_len); const AVOption *av_next_option(void *obj, const AVOption *last); int av_opt_show(void *obj, void *av_log_obj); void av_opt_set_defaults(void *s); void av_opt_set_defaults2(void *s, int mask, int flags); #endif /* AVCODEC_OPT_H */