forked from KolibriOS/kolibrios
911 lines
37 KiB
C
911 lines
37 KiB
C
/*
|
|
* 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
|
|
|
|
/**
|
|
* @file
|
|
* AVOptions
|
|
*/
|
|
|
|
#include "rational.h"
|
|
#include "avutil.h"
|
|
#include "dict.h"
|
|
#include "log.h"
|
|
#include "pixfmt.h"
|
|
#include "samplefmt.h"
|
|
#include "version.h"
|
|
|
|
/**
|
|
* @defgroup avoptions AVOptions
|
|
* @ingroup lavu_data
|
|
* @{
|
|
* AVOptions provide a generic system to declare options on arbitrary structs
|
|
* ("objects"). An option can have a help text, a type and a range of possible
|
|
* values. Options may then be enumerated, read and written to.
|
|
*
|
|
* @section avoptions_implement Implementing AVOptions
|
|
* This section describes how to add AVOptions capabilities to a struct.
|
|
*
|
|
* All AVOptions-related information is stored in an AVClass. Therefore
|
|
* the first member of the struct should be a pointer to an AVClass describing it.
|
|
* The option field of the AVClass must be set to a NULL-terminated static array
|
|
* of AVOptions. Each AVOption must have a non-empty name, a type, a default
|
|
* value and for number-type AVOptions also a range of allowed values. It must
|
|
* also declare an offset in bytes from the start of the struct, where the field
|
|
* associated with this AVOption is located. Other fields in the AVOption struct
|
|
* should also be set when applicable, but are not required.
|
|
*
|
|
* The following example illustrates an AVOptions-enabled struct:
|
|
* @code
|
|
* typedef struct test_struct {
|
|
* AVClass *class;
|
|
* int int_opt;
|
|
* char *str_opt;
|
|
* uint8_t *bin_opt;
|
|
* int bin_len;
|
|
* } test_struct;
|
|
*
|
|
* static const AVOption test_options[] = {
|
|
* { "test_int", "This is a test option of int type.", offsetof(test_struct, int_opt),
|
|
* AV_OPT_TYPE_INT, { .i64 = -1 }, INT_MIN, INT_MAX },
|
|
* { "test_str", "This is a test option of string type.", offsetof(test_struct, str_opt),
|
|
* AV_OPT_TYPE_STRING },
|
|
* { "test_bin", "This is a test option of binary type.", offsetof(test_struct, bin_opt),
|
|
* AV_OPT_TYPE_BINARY },
|
|
* { NULL },
|
|
* };
|
|
*
|
|
* static const AVClass test_class = {
|
|
* .class_name = "test class",
|
|
* .item_name = av_default_item_name,
|
|
* .option = test_options,
|
|
* .version = LIBAVUTIL_VERSION_INT,
|
|
* };
|
|
* @endcode
|
|
*
|
|
* Next, when allocating your struct, you must ensure that the AVClass pointer
|
|
* is set to the correct value. Then, av_opt_set_defaults() can be called to
|
|
* initialize defaults. After that the struct is ready to be used with the
|
|
* AVOptions API.
|
|
*
|
|
* When cleaning up, you may use the av_opt_free() function to automatically
|
|
* free all the allocated string and binary options.
|
|
*
|
|
* Continuing with the above example:
|
|
*
|
|
* @code
|
|
* test_struct *alloc_test_struct(void)
|
|
* {
|
|
* test_struct *ret = av_malloc(sizeof(*ret));
|
|
* ret->class = &test_class;
|
|
* av_opt_set_defaults(ret);
|
|
* return ret;
|
|
* }
|
|
* void free_test_struct(test_struct **foo)
|
|
* {
|
|
* av_opt_free(*foo);
|
|
* av_freep(foo);
|
|
* }
|
|
* @endcode
|
|
*
|
|
* @subsection avoptions_implement_nesting Nesting
|
|
* It may happen that an AVOptions-enabled struct contains another
|
|
* AVOptions-enabled struct as a member (e.g. AVCodecContext in
|
|
* libavcodec exports generic options, while its priv_data field exports
|
|
* codec-specific options). In such a case, it is possible to set up the
|
|
* parent struct to export a child's options. To do that, simply
|
|
* implement AVClass.child_next() and AVClass.child_class_next() in the
|
|
* parent struct's AVClass.
|
|
* Assuming that the test_struct from above now also contains a
|
|
* child_struct field:
|
|
*
|
|
* @code
|
|
* typedef struct child_struct {
|
|
* AVClass *class;
|
|
* int flags_opt;
|
|
* } child_struct;
|
|
* static const AVOption child_opts[] = {
|
|
* { "test_flags", "This is a test option of flags type.",
|
|
* offsetof(child_struct, flags_opt), AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT_MIN, INT_MAX },
|
|
* { NULL },
|
|
* };
|
|
* static const AVClass child_class = {
|
|
* .class_name = "child class",
|
|
* .item_name = av_default_item_name,
|
|
* .option = child_opts,
|
|
* .version = LIBAVUTIL_VERSION_INT,
|
|
* };
|
|
*
|
|
* void *child_next(void *obj, void *prev)
|
|
* {
|
|
* test_struct *t = obj;
|
|
* if (!prev && t->child_struct)
|
|
* return t->child_struct;
|
|
* return NULL
|
|
* }
|
|
* const AVClass child_class_next(const AVClass *prev)
|
|
* {
|
|
* return prev ? NULL : &child_class;
|
|
* }
|
|
* @endcode
|
|
* Putting child_next() and child_class_next() as defined above into
|
|
* test_class will now make child_struct's options accessible through
|
|
* test_struct (again, proper setup as described above needs to be done on
|
|
* child_struct right after it is created).
|
|
*
|
|
* From the above example it might not be clear why both child_next()
|
|
* and child_class_next() are needed. The distinction is that child_next()
|
|
* iterates over actually existing objects, while child_class_next()
|
|
* iterates over all possible child classes. E.g. if an AVCodecContext
|
|
* was initialized to use a codec which has private options, then its
|
|
* child_next() will return AVCodecContext.priv_data and finish
|
|
* iterating. OTOH child_class_next() on AVCodecContext.av_class will
|
|
* iterate over all available codecs with private options.
|
|
*
|
|
* @subsection avoptions_implement_named_constants Named constants
|
|
* It is possible to create named constants for options. Simply set the unit
|
|
* field of the option the constants should apply to a string and
|
|
* create the constants themselves as options of type AV_OPT_TYPE_CONST
|
|
* with their unit field set to the same string.
|
|
* Their default_val field should contain the value of the named
|
|
* constant.
|
|
* For example, to add some named constants for the test_flags option
|
|
* above, put the following into the child_opts array:
|
|
* @code
|
|
* { "test_flags", "This is a test option of flags type.",
|
|
* offsetof(child_struct, flags_opt), AV_OPT_TYPE_FLAGS, { .i64 = 0 }, INT_MIN, INT_MAX, "test_unit" },
|
|
* { "flag1", "This is a flag with value 16", 0, AV_OPT_TYPE_CONST, { .i64 = 16 }, 0, 0, "test_unit" },
|
|
* @endcode
|
|
*
|
|
* @section avoptions_use Using AVOptions
|
|
* This section deals with accessing options in an AVOptions-enabled struct.
|
|
* Such structs in FFmpeg are e.g. AVCodecContext in libavcodec or
|
|
* AVFormatContext in libavformat.
|
|
*
|
|
* @subsection avoptions_use_examine Examining AVOptions
|
|
* The basic functions for examining options are av_opt_next(), which iterates
|
|
* over all options defined for one object, and av_opt_find(), which searches
|
|
* for an option with the given name.
|
|
*
|
|
* The situation is more complicated with nesting. An AVOptions-enabled struct
|
|
* may have AVOptions-enabled children. Passing the AV_OPT_SEARCH_CHILDREN flag
|
|
* to av_opt_find() will make the function search children recursively.
|
|
*
|
|
* For enumerating there are basically two cases. The first is when you want to
|
|
* get all options that may potentially exist on the struct and its children
|
|
* (e.g. when constructing documentation). In that case you should call
|
|
* av_opt_child_class_next() recursively on the parent struct's AVClass. The
|
|
* second case is when you have an already initialized struct with all its
|
|
* children and you want to get all options that can be actually written or read
|
|
* from it. In that case you should call av_opt_child_next() recursively (and
|
|
* av_opt_next() on each result).
|
|
*
|
|
* @subsection avoptions_use_get_set Reading and writing AVOptions
|
|
* When setting options, you often have a string read directly from the
|
|
* user. In such a case, simply passing it to av_opt_set() is enough. For
|
|
* non-string type options, av_opt_set() will parse the string according to the
|
|
* option type.
|
|
*
|
|
* Similarly av_opt_get() will read any option type and convert it to a string
|
|
* which will be returned. Do not forget that the string is allocated, so you
|
|
* have to free it with av_free().
|
|
*
|
|
* In some cases it may be more convenient to put all options into an
|
|
* AVDictionary and call av_opt_set_dict() on it. A specific case of this
|
|
* are the format/codec open functions in lavf/lavc which take a dictionary
|
|
* filled with option as a parameter. This makes it possible to set some options
|
|
* that cannot be set otherwise, since e.g. the input file format is not known
|
|
* before the file is actually opened.
|
|
*/
|
|
|
|
enum AVOptionType{
|
|
AV_OPT_TYPE_FLAGS,
|
|
AV_OPT_TYPE_INT,
|
|
AV_OPT_TYPE_INT64,
|
|
AV_OPT_TYPE_DOUBLE,
|
|
AV_OPT_TYPE_FLOAT,
|
|
AV_OPT_TYPE_STRING,
|
|
AV_OPT_TYPE_RATIONAL,
|
|
AV_OPT_TYPE_BINARY, ///< offset must point to a pointer immediately followed by an int for the length
|
|
AV_OPT_TYPE_DICT,
|
|
AV_OPT_TYPE_CONST = 128,
|
|
AV_OPT_TYPE_IMAGE_SIZE = MKBETAG('S','I','Z','E'), ///< offset must point to two consecutive integers
|
|
AV_OPT_TYPE_PIXEL_FMT = MKBETAG('P','F','M','T'),
|
|
AV_OPT_TYPE_SAMPLE_FMT = MKBETAG('S','F','M','T'),
|
|
AV_OPT_TYPE_VIDEO_RATE = MKBETAG('V','R','A','T'), ///< offset must point to AVRational
|
|
AV_OPT_TYPE_DURATION = MKBETAG('D','U','R',' '),
|
|
AV_OPT_TYPE_COLOR = MKBETAG('C','O','L','R'),
|
|
AV_OPT_TYPE_CHANNEL_LAYOUT = MKBETAG('C','H','L','A'),
|
|
#if FF_API_OLD_AVOPTIONS
|
|
FF_OPT_TYPE_FLAGS = 0,
|
|
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,
|
|
#endif
|
|
};
|
|
|
|
/**
|
|
* 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
|
|
*/
|
|
union {
|
|
int64_t i64;
|
|
double dbl;
|
|
const char *str;
|
|
/* TODO those are unused now */
|
|
AVRational q;
|
|
} 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
|
|
#if FF_API_OPT_TYPE_METADATA
|
|
#define AV_OPT_FLAG_METADATA 4 ///< some data extracted or inserted into the file like title, comment, ...
|
|
#endif
|
|
#define AV_OPT_FLAG_AUDIO_PARAM 8
|
|
#define AV_OPT_FLAG_VIDEO_PARAM 16
|
|
#define AV_OPT_FLAG_SUBTITLE_PARAM 32
|
|
/**
|
|
* The option is inteded for exporting values to the caller.
|
|
*/
|
|
#define AV_OPT_FLAG_EXPORT 64
|
|
/**
|
|
* The option may not be set through the AVOptions API, only read.
|
|
* This flag only makes sense when AV_OPT_FLAG_EXPORT is also set.
|
|
*/
|
|
#define AV_OPT_FLAG_READONLY 128
|
|
#define AV_OPT_FLAG_FILTERING_PARAM (1<<16) ///< a generic parameter which can be set by the user for filtering
|
|
//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;
|
|
|
|
/**
|
|
* A single allowed range of values, or a single allowed value.
|
|
*/
|
|
typedef struct AVOptionRange {
|
|
const char *str;
|
|
/**
|
|
* Value range.
|
|
* For string ranges this represents the min/max length.
|
|
* For dimensions this represents the min/max pixel count or width/height in multi-component case.
|
|
*/
|
|
double value_min, value_max;
|
|
/**
|
|
* Value's component range.
|
|
* For string this represents the unicode range for chars, 0-127 limits to ASCII.
|
|
*/
|
|
double component_min, component_max;
|
|
/**
|
|
* Range flag.
|
|
* If set to 1 the struct encodes a range, if set to 0 a single value.
|
|
*/
|
|
int is_range;
|
|
} AVOptionRange;
|
|
|
|
/**
|
|
* List of AVOptionRange structs.
|
|
*/
|
|
typedef struct AVOptionRanges {
|
|
/**
|
|
* Array of option ranges.
|
|
*
|
|
* Most of option types use just one component.
|
|
* Following describes multi-component option types:
|
|
*
|
|
* AV_OPT_TYPE_IMAGE_SIZE:
|
|
* component index 0: range of pixel count (width * height).
|
|
* component index 1: range of width.
|
|
* component index 2: range of height.
|
|
*
|
|
* @note To obtain multi-component version of this structure, user must
|
|
* provide AV_OPT_MULTI_COMPONENT_RANGE to av_opt_query_ranges or
|
|
* av_opt_query_ranges_default function.
|
|
*
|
|
* Multi-component range can be read as in following example:
|
|
*
|
|
* @code
|
|
* int range_index, component_index;
|
|
* AVOptionRanges *ranges;
|
|
* AVOptionRange *range[3]; //may require more than 3 in the future.
|
|
* av_opt_query_ranges(&ranges, obj, key, AV_OPT_MULTI_COMPONENT_RANGE);
|
|
* for (range_index = 0; range_index < ranges->nb_ranges; range_index++) {
|
|
* for (component_index = 0; component_index < ranges->nb_components; component_index++)
|
|
* range[component_index] = ranges->range[ranges->nb_ranges * component_index + range_index];
|
|
* //do something with range here.
|
|
* }
|
|
* av_opt_freep_ranges(&ranges);
|
|
* @endcode
|
|
*/
|
|
AVOptionRange **range;
|
|
/**
|
|
* Number of ranges per component.
|
|
*/
|
|
int nb_ranges;
|
|
/**
|
|
* Number of componentes.
|
|
*/
|
|
int nb_components;
|
|
} AVOptionRanges;
|
|
|
|
|
|
#if FF_API_OLD_AVOPTIONS
|
|
/**
|
|
* Set 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.
|
|
* @param[out] o_out if non-NULL put here a pointer to the AVOption
|
|
* found
|
|
* @param alloc this parameter is currently ignored
|
|
* @return 0 if the value has been set, or an AVERROR code in case of
|
|
* error:
|
|
* AVERROR_OPTION_NOT_FOUND if no matching option exists
|
|
* AVERROR(ERANGE) if the value is out of range
|
|
* AVERROR(EINVAL) if the value is not valid
|
|
* @deprecated use av_opt_set()
|
|
*/
|
|
attribute_deprecated
|
|
int av_set_string3(void *obj, const char *name, const char *val, int alloc, const AVOption **o_out);
|
|
|
|
attribute_deprecated const AVOption *av_set_double(void *obj, const char *name, double n);
|
|
attribute_deprecated const AVOption *av_set_q(void *obj, const char *name, AVRational n);
|
|
attribute_deprecated const AVOption *av_set_int(void *obj, const char *name, int64_t n);
|
|
|
|
attribute_deprecated
|
|
double av_get_double(void *obj, const char *name, const AVOption **o_out);
|
|
attribute_deprecated
|
|
AVRational av_get_q(void *obj, const char *name, const AVOption **o_out);
|
|
attribute_deprecated
|
|
int64_t av_get_int(void *obj, const char *name, const AVOption **o_out);
|
|
attribute_deprecated const char *av_get_string(void *obj, const char *name, const AVOption **o_out, char *buf, int buf_len);
|
|
attribute_deprecated const AVOption *av_next_option(FF_CONST_AVUTIL55 void *obj, const AVOption *last);
|
|
#endif
|
|
|
|
/**
|
|
* Show the obj options.
|
|
*
|
|
* @param req_flags requested flags for the options to show. Show only the
|
|
* options for which it is opt->flags & req_flags.
|
|
* @param rej_flags rejected flags for the options to show. Show only the
|
|
* options for which it is !(opt->flags & req_flags).
|
|
* @param av_log_obj log context to use for showing the options
|
|
*/
|
|
int av_opt_show2(void *obj, void *av_log_obj, int req_flags, int rej_flags);
|
|
|
|
/**
|
|
* Set the values of all AVOption fields to their default values.
|
|
*
|
|
* @param s an AVOption-enabled struct (its first member must be a pointer to AVClass)
|
|
*/
|
|
void av_opt_set_defaults(void *s);
|
|
|
|
/**
|
|
* Set the values of all AVOption fields to their default values. Only these
|
|
* AVOption fields for which (opt->flags & mask) == flags will have their
|
|
* default applied to s.
|
|
*
|
|
* @param s an AVOption-enabled struct (its first member must be a pointer to AVClass)
|
|
* @param mask combination of AV_OPT_FLAG_*
|
|
* @param flags combination of AV_OPT_FLAG_*
|
|
*/
|
|
void av_opt_set_defaults2(void *s, int mask, int flags);
|
|
|
|
/**
|
|
* Parse the key/value pairs list in opts. For each key/value pair
|
|
* found, stores the value in the field in ctx that is named like the
|
|
* key. ctx must be an AVClass context, storing is done using
|
|
* AVOptions.
|
|
*
|
|
* @param opts options string to parse, may be NULL
|
|
* @param key_val_sep a 0-terminated list of characters used to
|
|
* separate key from value
|
|
* @param pairs_sep a 0-terminated list of characters used to separate
|
|
* two pairs from each other
|
|
* @return the number of successfully set key/value pairs, or a negative
|
|
* value corresponding to an AVERROR code in case of error:
|
|
* AVERROR(EINVAL) if opts cannot be parsed,
|
|
* the error code issued by av_opt_set() if a key/value pair
|
|
* cannot be set
|
|
*/
|
|
int av_set_options_string(void *ctx, const char *opts,
|
|
const char *key_val_sep, const char *pairs_sep);
|
|
|
|
/**
|
|
* Parse the key-value pairs list in opts. For each key=value pair found,
|
|
* set the value of the corresponding option in ctx.
|
|
*
|
|
* @param ctx the AVClass object to set options on
|
|
* @param opts the options string, key-value pairs separated by a
|
|
* delimiter
|
|
* @param shorthand a NULL-terminated array of options names for shorthand
|
|
* notation: if the first field in opts has no key part,
|
|
* the key is taken from the first element of shorthand;
|
|
* then again for the second, etc., until either opts is
|
|
* finished, shorthand is finished or a named option is
|
|
* found; after that, all options must be named
|
|
* @param key_val_sep a 0-terminated list of characters used to separate
|
|
* key from value, for example '='
|
|
* @param pairs_sep a 0-terminated list of characters used to separate
|
|
* two pairs from each other, for example ':' or ','
|
|
* @return the number of successfully set key=value pairs, or a negative
|
|
* value corresponding to an AVERROR code in case of error:
|
|
* AVERROR(EINVAL) if opts cannot be parsed,
|
|
* the error code issued by av_set_string3() if a key/value pair
|
|
* cannot be set
|
|
*
|
|
* Options names must use only the following characters: a-z A-Z 0-9 - . / _
|
|
* Separators must use characters distinct from option names and from each
|
|
* other.
|
|
*/
|
|
int av_opt_set_from_string(void *ctx, const char *opts,
|
|
const char *const *shorthand,
|
|
const char *key_val_sep, const char *pairs_sep);
|
|
/**
|
|
* Free all allocated objects in obj.
|
|
*/
|
|
void av_opt_free(void *obj);
|
|
|
|
/**
|
|
* Check whether a particular flag is set in a flags field.
|
|
*
|
|
* @param field_name the name of the flag field option
|
|
* @param flag_name the name of the flag to check
|
|
* @return non-zero if the flag is set, zero if the flag isn't set,
|
|
* isn't of the right type, or the flags field doesn't exist.
|
|
*/
|
|
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);
|
|
|
|
|
|
/**
|
|
* 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().
|
|
* @param search_flags A combination of AV_OPT_SEARCH_*.
|
|
*
|
|
* @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_dict2(void *obj, struct AVDictionary **options, int search_flags);
|
|
|
|
/**
|
|
* Extract a key-value pair from the beginning of a string.
|
|
*
|
|
* @param ropts pointer to the options string, will be updated to
|
|
* point to the rest of the string (one of the pairs_sep
|
|
* or the final NUL)
|
|
* @param key_val_sep a 0-terminated list of characters used to separate
|
|
* key from value, for example '='
|
|
* @param pairs_sep a 0-terminated list of characters used to separate
|
|
* two pairs from each other, for example ':' or ','
|
|
* @param flags flags; see the AV_OPT_FLAG_* values below
|
|
* @param rkey parsed key; must be freed using av_free()
|
|
* @param rval parsed value; must be freed using av_free()
|
|
*
|
|
* @return >=0 for success, or a negative value corresponding to an
|
|
* AVERROR code in case of error; in particular:
|
|
* AVERROR(EINVAL) if no key is present
|
|
*
|
|
*/
|
|
int av_opt_get_key_value(const char **ropts,
|
|
const char *key_val_sep, const char *pairs_sep,
|
|
unsigned flags,
|
|
char **rkey, char **rval);
|
|
|
|
enum {
|
|
|
|
/**
|
|
* Accept to parse a value without a key; the key will then be returned
|
|
* as NULL.
|
|
*/
|
|
AV_OPT_FLAG_IMPLICIT_KEY = 1,
|
|
};
|
|
|
|
/**
|
|
* @defgroup opt_eval_funcs Evaluating option strings
|
|
* @{
|
|
* This group of functions can be used to evaluate option strings
|
|
* and get numbers out of them. They do the same thing as av_opt_set(),
|
|
* except the result is written into the caller-supplied pointer.
|
|
*
|
|
* @param obj a struct whose first element is a pointer to AVClass.
|
|
* @param o an option for which the string is to be evaluated.
|
|
* @param val string to be evaluated.
|
|
* @param *_out value of the string will be written here.
|
|
*
|
|
* @return 0 on success, a negative number on failure.
|
|
*/
|
|
int av_opt_eval_flags (void *obj, const AVOption *o, const char *val, int *flags_out);
|
|
int av_opt_eval_int (void *obj, const AVOption *o, const char *val, int *int_out);
|
|
int av_opt_eval_int64 (void *obj, const AVOption *o, const char *val, int64_t *int64_out);
|
|
int av_opt_eval_float (void *obj, const AVOption *o, const char *val, float *float_out);
|
|
int av_opt_eval_double(void *obj, const AVOption *o, const char *val, double *double_out);
|
|
int av_opt_eval_q (void *obj, const AVOption *o, const char *val, AVRational *q_out);
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
#define AV_OPT_SEARCH_CHILDREN 0x0001 /**< Search in possible children of the
|
|
given object first. */
|
|
/**
|
|
* The obj passed to av_opt_find() is fake -- only a double pointer to AVClass
|
|
* instead of a required pointer to a struct containing AVClass. This is
|
|
* useful for searching for options without needing to allocate the corresponding
|
|
* object.
|
|
*/
|
|
#define AV_OPT_SEARCH_FAKE_OBJ 0x0002
|
|
|
|
/**
|
|
* Allows av_opt_query_ranges and av_opt_query_ranges_default to return more than
|
|
* one component for certain option types.
|
|
* @see AVOptionRanges for details.
|
|
*/
|
|
#define AV_OPT_MULTI_COMPONENT_RANGE 0x1000
|
|
|
|
/**
|
|
* Look for an option in an object. Consider only options which
|
|
* have all the specified flags set.
|
|
*
|
|
* @param[in] obj A pointer to a struct whose first element is a
|
|
* pointer to an AVClass.
|
|
* Alternatively a double pointer to an AVClass, if
|
|
* AV_OPT_SEARCH_FAKE_OBJ search flag is set.
|
|
* @param[in] name The name of the option to look for.
|
|
* @param[in] unit When searching for named constants, name of the unit
|
|
* it belongs to.
|
|
* @param opt_flags Find only options with all the specified flags set (AV_OPT_FLAG).
|
|
* @param search_flags A combination of AV_OPT_SEARCH_*.
|
|
*
|
|
* @return A pointer to the option found, or NULL if no option
|
|
* was found.
|
|
*
|
|
* @note Options found with AV_OPT_SEARCH_CHILDREN flag may not be settable
|
|
* directly with av_opt_set(). Use special calls which take an options
|
|
* AVDictionary (e.g. avformat_open_input()) to set options found with this
|
|
* flag.
|
|
*/
|
|
const AVOption *av_opt_find(void *obj, const char *name, const char *unit,
|
|
int opt_flags, int search_flags);
|
|
|
|
/**
|
|
* Look for an option in an object. Consider only options which
|
|
* have all the specified flags set.
|
|
*
|
|
* @param[in] obj A pointer to a struct whose first element is a
|
|
* pointer to an AVClass.
|
|
* Alternatively a double pointer to an AVClass, if
|
|
* AV_OPT_SEARCH_FAKE_OBJ search flag is set.
|
|
* @param[in] name The name of the option to look for.
|
|
* @param[in] unit When searching for named constants, name of the unit
|
|
* it belongs to.
|
|
* @param opt_flags Find only options with all the specified flags set (AV_OPT_FLAG).
|
|
* @param search_flags A combination of AV_OPT_SEARCH_*.
|
|
* @param[out] target_obj if non-NULL, an object to which the option belongs will be
|
|
* written here. It may be different from obj if AV_OPT_SEARCH_CHILDREN is present
|
|
* in search_flags. This parameter is ignored if search_flags contain
|
|
* AV_OPT_SEARCH_FAKE_OBJ.
|
|
*
|
|
* @return A pointer to the option found, or NULL if no option
|
|
* was found.
|
|
*/
|
|
const AVOption *av_opt_find2(void *obj, const char *name, const char *unit,
|
|
int opt_flags, int search_flags, void **target_obj);
|
|
|
|
/**
|
|
* Iterate over all AVOptions belonging to obj.
|
|
*
|
|
* @param obj an AVOptions-enabled struct or a double pointer to an
|
|
* AVClass describing it.
|
|
* @param prev result of the previous call to av_opt_next() on this object
|
|
* or NULL
|
|
* @return next AVOption or NULL
|
|
*/
|
|
const AVOption *av_opt_next(FF_CONST_AVUTIL55 void *obj, const AVOption *prev);
|
|
|
|
/**
|
|
* Iterate over AVOptions-enabled children of obj.
|
|
*
|
|
* @param prev result of a previous call to this function or NULL
|
|
* @return next AVOptions-enabled child or NULL
|
|
*/
|
|
void *av_opt_child_next(void *obj, void *prev);
|
|
|
|
/**
|
|
* Iterate over potential AVOptions-enabled children of parent.
|
|
*
|
|
* @param prev result of a previous call to this function or NULL
|
|
* @return AVClass corresponding to next potential child or NULL
|
|
*/
|
|
const AVClass *av_opt_child_class_next(const AVClass *parent, const AVClass *prev);
|
|
|
|
/**
|
|
* @defgroup opt_set_funcs Option setting functions
|
|
* @{
|
|
* Those functions set 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. In case of av_opt_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.
|
|
* @param search_flags flags passed to av_opt_find2. I.e. if AV_OPT_SEARCH_CHILDREN
|
|
* is passed here, then the option may be set on a child of obj.
|
|
*
|
|
* @return 0 if the value has been set, or an AVERROR code in case of
|
|
* error:
|
|
* AVERROR_OPTION_NOT_FOUND if no matching option exists
|
|
* AVERROR(ERANGE) if the value is out of range
|
|
* AVERROR(EINVAL) if the value is not valid
|
|
*/
|
|
int av_opt_set (void *obj, const char *name, const char *val, int search_flags);
|
|
int av_opt_set_int (void *obj, const char *name, int64_t val, int search_flags);
|
|
int av_opt_set_double (void *obj, const char *name, double val, int search_flags);
|
|
int av_opt_set_q (void *obj, const char *name, AVRational val, int search_flags);
|
|
int av_opt_set_bin (void *obj, const char *name, const uint8_t *val, int size, int search_flags);
|
|
int av_opt_set_image_size(void *obj, const char *name, int w, int h, int search_flags);
|
|
int av_opt_set_pixel_fmt (void *obj, const char *name, enum AVPixelFormat fmt, int search_flags);
|
|
int av_opt_set_sample_fmt(void *obj, const char *name, enum AVSampleFormat fmt, int search_flags);
|
|
int av_opt_set_video_rate(void *obj, const char *name, AVRational val, int search_flags);
|
|
int av_opt_set_channel_layout(void *obj, const char *name, int64_t ch_layout, int search_flags);
|
|
/**
|
|
* @note Any old dictionary present is discarded and replaced with a copy of the new one. The
|
|
* caller still owns val is and responsible for freeing it.
|
|
*/
|
|
int av_opt_set_dict_val(void *obj, const char *name, const AVDictionary *val, int search_flags);
|
|
|
|
/**
|
|
* Set a binary option to an integer list.
|
|
*
|
|
* @param obj AVClass object to set options on
|
|
* @param name name of the binary option
|
|
* @param val pointer to an integer list (must have the correct type with
|
|
* regard to the contents of the list)
|
|
* @param term list terminator (usually 0 or -1)
|
|
* @param flags search flags
|
|
*/
|
|
#define av_opt_set_int_list(obj, name, val, term, flags) \
|
|
(av_int_list_length(val, term) > INT_MAX / sizeof(*(val)) ? \
|
|
AVERROR(EINVAL) : \
|
|
av_opt_set_bin(obj, name, (const uint8_t *)(val), \
|
|
av_int_list_length(val, term) * sizeof(*(val)), flags))
|
|
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
/**
|
|
* @defgroup opt_get_funcs Option getting functions
|
|
* @{
|
|
* Those functions get a value of the option with the given name from an object.
|
|
*
|
|
* @param[in] obj a struct whose first element is a pointer to an AVClass.
|
|
* @param[in] name name of the option to get.
|
|
* @param[in] search_flags flags passed to av_opt_find2. I.e. if AV_OPT_SEARCH_CHILDREN
|
|
* is passed here, then the option may be found in a child of obj.
|
|
* @param[out] out_val value of the option will be written here
|
|
* @return >=0 on success, a negative error code otherwise
|
|
*/
|
|
/**
|
|
* @note the returned string will be av_malloc()ed and must be av_free()ed by the caller
|
|
*/
|
|
int av_opt_get (void *obj, const char *name, int search_flags, uint8_t **out_val);
|
|
int av_opt_get_int (void *obj, const char *name, int search_flags, int64_t *out_val);
|
|
int av_opt_get_double (void *obj, const char *name, int search_flags, double *out_val);
|
|
int av_opt_get_q (void *obj, const char *name, int search_flags, AVRational *out_val);
|
|
int av_opt_get_image_size(void *obj, const char *name, int search_flags, int *w_out, int *h_out);
|
|
int av_opt_get_pixel_fmt (void *obj, const char *name, int search_flags, enum AVPixelFormat *out_fmt);
|
|
int av_opt_get_sample_fmt(void *obj, const char *name, int search_flags, enum AVSampleFormat *out_fmt);
|
|
int av_opt_get_video_rate(void *obj, const char *name, int search_flags, AVRational *out_val);
|
|
int av_opt_get_channel_layout(void *obj, const char *name, int search_flags, int64_t *ch_layout);
|
|
/**
|
|
* @param[out] out_val The returned dictionary is a copy of the actual value and must
|
|
* be freed with av_dict_free() by the caller
|
|
*/
|
|
int av_opt_get_dict_val(void *obj, const char *name, int search_flags, AVDictionary **out_val);
|
|
/**
|
|
* @}
|
|
*/
|
|
/**
|
|
* Gets a pointer to the requested field in a struct.
|
|
* This function allows accessing a struct even when its fields are moved or
|
|
* renamed since the application making the access has been compiled,
|
|
*
|
|
* @returns a pointer to the field, it can be cast to the correct type and read
|
|
* or written to.
|
|
*/
|
|
void *av_opt_ptr(const AVClass *avclass, void *obj, const char *name);
|
|
|
|
/**
|
|
* Free an AVOptionRanges struct and set it to NULL.
|
|
*/
|
|
void av_opt_freep_ranges(AVOptionRanges **ranges);
|
|
|
|
/**
|
|
* Get a list of allowed ranges for the given option.
|
|
*
|
|
* The returned list may depend on other fields in obj like for example profile.
|
|
*
|
|
* @param flags is a bitmask of flags, undefined flags should not be set and should be ignored
|
|
* AV_OPT_SEARCH_FAKE_OBJ indicates that the obj is a double pointer to a AVClass instead of a full instance
|
|
* AV_OPT_MULTI_COMPONENT_RANGE indicates that function may return more than one component, @see AVOptionRanges
|
|
*
|
|
* The result must be freed with av_opt_freep_ranges.
|
|
*
|
|
* @return number of compontents returned on success, a negative errro code otherwise
|
|
*/
|
|
int av_opt_query_ranges(AVOptionRanges **, void *obj, const char *key, int flags);
|
|
|
|
/**
|
|
* Copy options from src object into dest object.
|
|
*
|
|
* Options that require memory allocation (e.g. string or binary) are malloc'ed in dest object.
|
|
* Original memory allocated for such options is freed unless both src and dest options points to the same memory.
|
|
*
|
|
* @param dest Object to copy from
|
|
* @param src Object to copy into
|
|
* @return 0 on success, negative on error
|
|
*/
|
|
int av_opt_copy(void *dest, FF_CONST_AVUTIL55 void *src);
|
|
|
|
/**
|
|
* Get a default list of allowed ranges for the given option.
|
|
*
|
|
* This list is constructed without using the AVClass.query_ranges() callback
|
|
* and can be used as fallback from within the callback.
|
|
*
|
|
* @param flags is a bitmask of flags, undefined flags should not be set and should be ignored
|
|
* AV_OPT_SEARCH_FAKE_OBJ indicates that the obj is a double pointer to a AVClass instead of a full instance
|
|
* AV_OPT_MULTI_COMPONENT_RANGE indicates that function may return more than one component, @see AVOptionRanges
|
|
*
|
|
* The result must be freed with av_opt_free_ranges.
|
|
*
|
|
* @return number of compontents returned on success, a negative errro code otherwise
|
|
*/
|
|
int av_opt_query_ranges_default(AVOptionRanges **, void *obj, const char *key, int flags);
|
|
|
|
/**
|
|
* Check if given option is set to its default value.
|
|
*
|
|
* Options o must belong to the obj. This function must not be called to check child's options state.
|
|
* @see av_opt_is_set_to_default_by_name().
|
|
*
|
|
* @param obj AVClass object to check option on
|
|
* @param o option to be checked
|
|
* @return >0 when option is set to its default,
|
|
* 0 when option is not set its default,
|
|
* <0 on error
|
|
*/
|
|
int av_opt_is_set_to_default(void *obj, const AVOption *o);
|
|
|
|
/**
|
|
* Check if given option is set to its default value.
|
|
*
|
|
* @param obj AVClass object to check option on
|
|
* @param name option name
|
|
* @param search_flags combination of AV_OPT_SEARCH_*
|
|
* @return >0 when option is set to its default,
|
|
* 0 when option is not set its default,
|
|
* <0 on error
|
|
*/
|
|
int av_opt_is_set_to_default_by_name(void *obj, const char *name, int search_flags);
|
|
|
|
|
|
#define AV_OPT_SERIALIZE_SKIP_DEFAULTS 0x00000001 ///< Serialize options that are not set to default values only.
|
|
#define AV_OPT_SERIALIZE_OPT_FLAGS_EXACT 0x00000002 ///< Serialize options that exactly match opt_flags only.
|
|
|
|
/**
|
|
* Serialize object's options.
|
|
*
|
|
* Create a string containing object's serialized options.
|
|
* Such string may be passed back to av_opt_set_from_string() in order to restore option values.
|
|
* A key/value or pairs separator occurring in the serialized value or
|
|
* name string are escaped through the av_escape() function.
|
|
*
|
|
* @param[in] obj AVClass object to serialize
|
|
* @param[in] opt_flags serialize options with all the specified flags set (AV_OPT_FLAG)
|
|
* @param[in] flags combination of AV_OPT_SERIALIZE_* flags
|
|
* @param[out] buffer Pointer to buffer that will be allocated with string containg serialized options.
|
|
* Buffer must be freed by the caller when is no longer needed.
|
|
* @param[in] key_val_sep character used to separate key from value
|
|
* @param[in] pairs_sep character used to separate two pairs from each other
|
|
* @return >= 0 on success, negative on error
|
|
* @warning Separators cannot be neither '\\' nor '\0'. They also cannot be the same.
|
|
*/
|
|
int av_opt_serialize(void *obj, int opt_flags, int flags, char **buffer,
|
|
const char key_val_sep, const char pairs_sep);
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
#endif /* AVUTIL_OPT_H */
|