libavutil/opt.h

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/*
 * 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 AVUTIL_OPT_H
#define AVUTIL_OPT_H

#include "rational.h"
#include "avutil.h"
#include "dict.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,  
    FF_OPT_TYPE_CONST=128,
};

typedef struct AVOption {
    const char *name;

    const char *help;

    int offset;
    enum AVOptionType type;

    union {
        double dbl;
        const char *str;
        /* TODO those are unused now */
        int64_t i64;
        AVRational q;
    } default_val;
    double min;                 
    double max;                 

    int flags;
#define AV_OPT_FLAG_ENCODING_PARAM  1   
#define AV_OPT_FLAG_DECODING_PARAM  2   
#define AV_OPT_FLAG_METADATA        4   
#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

    const char *unit;
} AVOption;

#if FF_API_FIND_OPT

attribute_deprecated
const AVOption *av_find_opt(void *obj, const char *name, const char *unit, int mask, int flags);
#endif

int av_set_string3(void *obj, const char *name, const char *val, int alloc, const AVOption **o_out);

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_show2(void *obj, void *av_log_obj, int req_flags, int rej_flags);

void av_opt_set_defaults(void *s);
void av_opt_set_defaults2(void *s, int mask, int flags);

int av_set_options_string(void *ctx, const char *opts,
                          const char *key_val_sep, const char *pairs_sep);

void av_opt_free(void *obj);

int av_opt_flag_is_set(void *obj, const char *field_name, const char *flag_name);

/*
 * Set all the options from a given dictionary on an object.
 *
 * @param obj a struct whose first element is a pointer to AVClass
 * @param options options to process. This dictionary will be freed and replaced
 *                by a new one containing all options not found in obj.
 *                Of course this new dictionary needs to be freed by caller
 *                with av_dict_free().
 *
 * @return 0 on success, a negative AVERROR if some option was found in obj,
 *         but could not be set.
 *
 * @see av_dict_copy()
 */
int av_opt_set_dict(void *obj, struct AVDictionary **options);

#define AV_OPT_SEARCH_CHILDREN   0x0001 
const AVOption *av_opt_find(void *obj, const char *name, const char *unit,
                            int opt_flags, int search_flags);

#endif /* AVUTIL_OPT_H */

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