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/*
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 * AVOptions
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 * copyright (c) 2005 Michael Niedermayer <michaelni@gmx.at>
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 *
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 * This file is part of Libav.
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 *
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 * Libav is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * Libav is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with Libav; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef AVUTIL_OPT_H
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#define AVUTIL_OPT_H
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/**
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 * @file
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 * AVOptions
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 */
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#include "rational.h"
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#include "avutil.h"
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enum AVOptionType{
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    FF_OPT_TYPE_FLAGS,
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    FF_OPT_TYPE_INT,
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    FF_OPT_TYPE_INT64,
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    FF_OPT_TYPE_DOUBLE,
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    FF_OPT_TYPE_FLOAT,
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    FF_OPT_TYPE_STRING,
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    FF_OPT_TYPE_RATIONAL,
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    FF_OPT_TYPE_BINARY,  ///< offset must point to a pointer immediately followed by an int for the length
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    FF_OPT_TYPE_CONST=128,
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};
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/**
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 * AVOption
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 */
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typedef struct AVOption {
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    const char *name;
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    /**
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     * short English help text
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     * @todo What about other languages?
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     */
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    const char *help;
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    /**
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     * The offset relative to the context structure where the option
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     * value is stored. It should be 0 for named constants.
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     */
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    int offset;
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    enum AVOptionType type;
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    /**
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     * the default value for scalar options
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     */
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    union {
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        double dbl;
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        const char *str;
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        /* TODO those are unused now */
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        int64_t i64;
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        AVRational q;
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    } default_val;
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    double min;                 ///< minimum valid value for the option
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    double max;                 ///< maximum valid value for the option
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    int flags;
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#define AV_OPT_FLAG_ENCODING_PARAM  1   ///< a generic parameter which can be set by the user for muxing or encoding
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#define AV_OPT_FLAG_DECODING_PARAM  2   ///< a generic parameter which can be set by the user for demuxing or decoding
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#define AV_OPT_FLAG_METADATA        4   ///< some data extracted or inserted into the file like title, comment, ...
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#define AV_OPT_FLAG_AUDIO_PARAM     8
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#define AV_OPT_FLAG_VIDEO_PARAM     16
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#define AV_OPT_FLAG_SUBTITLE_PARAM  32
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//FIXME think about enc-audio, ... style flags
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    /**
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     * The logical unit to which the option belongs. Non-constant
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     * options and corresponding named constants share the same
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     * unit. May be NULL.
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     */
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    const char *unit;
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} AVOption;
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/**
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 * Look for an option in obj. Look only for the options which
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 * have the flags set as specified in mask and flags (that is,
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 * for which it is the case that opt->flags & mask == flags).
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 *
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 * @param[in] obj a pointer to a struct whose first element is a
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 * pointer to an AVClass
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 * @param[in] name the name of the option to look for
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 * @param[in] unit the unit of the option to look for, or any if NULL
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 * @return a pointer to the option found, or NULL if no option
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 * has been found
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 */
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const AVOption *av_find_opt(void *obj, const char *name, const char *unit, int mask, int flags);
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/**
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 * Set the field of obj with the given name to value.
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 *
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 * @param[in] obj A struct whose first element is a pointer to an
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 * AVClass.
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 * @param[in] name the name of the field to set
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 * @param[in] val The value to set. If the field is not of a string
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 * type, then the given string is parsed.
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 * SI postfixes and some named scalars are supported.
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 * If the field is of a numeric type, it has to be a numeric or named
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 * scalar. Behavior with more than one scalar and +- infix operators
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 * is undefined.
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 * If the field is of a flags type, it has to be a sequence of numeric
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 * scalars or named flags separated by '+' or '-'. Prefixing a flag
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 * with '+' causes it to be set without affecting the other flags;
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 * similarly, '-' unsets a flag.
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 * @param[out] o_out if non-NULL put here a pointer to the AVOption
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 * found
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 * @param alloc when 1 then the old value will be av_freed() and the
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 *                     new av_strduped()
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 *              when 0 then no av_free() nor av_strdup() will be used
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 * @return 0 if the value has been set, or an AVERROR code in case of
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 * error:
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 * AVERROR(ENOENT) if no matching option exists
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 * AVERROR(ERANGE) if the value is out of range
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 * AVERROR(EINVAL) if the value is not valid
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 */
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int av_set_string3(void *obj, const char *name, const char *val, int alloc, const AVOption **o_out);
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const AVOption *av_set_double(void *obj, const char *name, double n);
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const AVOption *av_set_q(void *obj, const char *name, AVRational n);
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const AVOption *av_set_int(void *obj, const char *name, int64_t n);
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double av_get_double(void *obj, const char *name, const AVOption **o_out);
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AVRational av_get_q(void *obj, const char *name, const AVOption **o_out);
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int64_t av_get_int(void *obj, const char *name, const AVOption **o_out);
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const char *av_get_string(void *obj, const char *name, const AVOption **o_out, char *buf, int buf_len);
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const AVOption *av_next_option(void *obj, const AVOption *last);
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/**
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 * Show the obj options.
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 *
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 * @param req_flags requested flags for the options to show. Show only the
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 * options for which it is opt->flags & req_flags.
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 * @param rej_flags rejected flags for the options to show. Show only the
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 * options for which it is !(opt->flags & req_flags).
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 * @param av_log_obj log context to use for showing the options
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 */
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int av_opt_show2(void *obj, void *av_log_obj, int req_flags, int rej_flags);
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void av_opt_set_defaults(void *s);
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void av_opt_set_defaults2(void *s, int mask, int flags);
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/**
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 * Parse the key/value pairs list in opts. For each key/value pair
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 * found, stores the value in the field in ctx that is named like the
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 * key. ctx must be an AVClass context, storing is done using
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 * AVOptions.
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 *
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 * @param key_val_sep a 0-terminated list of characters used to
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 * separate key from value
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 * @param pairs_sep a 0-terminated list of characters used to separate
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 * two pairs from each other
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 * @return the number of successfully set key/value pairs, or a negative
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 * value corresponding to an AVERROR code in case of error:
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 * AVERROR(EINVAL) if opts cannot be parsed,
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 * the error code issued by av_set_string3() if a key/value pair
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 * cannot be set
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 */
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int av_set_options_string(void *ctx, const char *opts,
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                          const char *key_val_sep, const char *pairs_sep);
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#endif /* AVUTIL_OPT_H */