FFmpeg: Option getting functions

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Functions

Option getting functions

libavutil » Data Structures » AVOptions » Reading option values

Those functions get a value of the option with the given name from an object. More...

Functions

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_chlayout (void *obj, const char *name, int search_flags, AVChannelLayout *layout)

int av_opt_get_dict_val (void *obj, const char *name, int search_flags, AVDictionary **out_val)

int av_opt_get_array_size (void *obj, const char *name, int search_flags, unsigned int *out_val)

For an array-type option, get the number of elements in the array. More...

int av_opt_get_array (void *obj, const char *name, int search_flags, unsigned int start_elem, unsigned int nb_elems, enum AVOptionType out_type, void *out_val)

For an array-type option, retrieve the values of one or more array elements. More...

Detailed Description

Those functions get a value of the option with the given name from an object.

Parameters: [in] obj a struct whose first element is a pointer to an AVClass.

[in] name name of the option to get.

[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.

[out] out_val value of the option will be written here

Returns: >=0 on success, a negative error code otherwise

Function Documentation

◆ av_opt_get()

int av_opt_get ( void * obj,

const char * name,

int search_flags,

uint8_t ** out_val

)

Note: the returned string will be av_malloc()ed and must be av_free()ed by the caller; if AV_OPT_ALLOW_NULL is set in search_flags in av_opt_get, and the option is of type AV_OPT_TYPE_STRING, AV_OPT_TYPE_BINARY or AV_OPT_TYPE_DICT and is set to NULL, *out_val will be set to NULL instead of an allocated empty string.

Definition at line 1215 of file opt.c.

Referenced by av_probe_input_buffer2(), config_props(), ff_rtp_chain_mux_open(), ffio_copy_url_options(), main(), mpjpeg_get_boundary(), open_url(), opt_serialize(), parse_manifest(), parse_playlist(), pcm_read_header(), print_private_data(), process_client(), and read_data_continuous().

◆ av_opt_get_int()

int av_opt_get_int ( void * obj,

const char * name,

int search_flags,

int64_t * out_val

)

Definition at line 1273 of file opt.c.

Referenced by av_opt_flag_is_set(), config_output(), ff_frame_thread_encoder_init(), ff_rtp_get_payload_type(), ist_use(), opus_decode_subpacket(), ost_bind_filter(), and query_formats().

◆ av_opt_get_double()

int av_opt_get_double ( void * obj,

const char * name,

int search_flags,

double * out_val

)

Definition at line 1288 of file opt.c.

◆ av_opt_get_q()

int av_opt_get_q ( void * obj,

const char * name,

int search_flags,

AVRational * out_val

)

Definition at line 1300 of file opt.c.

Referenced by av_opt_get_video_rate().

◆ av_opt_get_image_size()

int av_opt_get_image_size ( void * obj,

const char * name,

int search_flags,

int * w_out,

int * h_out

)

Definition at line 1316 of file opt.c.

◆ av_opt_get_pixel_fmt()

int av_opt_get_pixel_fmt ( void * obj,

const char * name,

int search_flags,

enum AVPixelFormat * out_fmt

)

Definition at line 1357 of file opt.c.

◆ av_opt_get_sample_fmt()

int av_opt_get_sample_fmt ( void * obj,

const char * name,

int search_flags,

enum AVSampleFormat * out_fmt

)

Definition at line 1362 of file opt.c.

Referenced by config_output(), and query_formats().

◆ av_opt_get_video_rate()

int av_opt_get_video_rate ( void * obj,

const char * name,

int search_flags,

AVRational * out_val

)

Definition at line 1334 of file opt.c.

◆ av_opt_get_chlayout()

int av_opt_get_chlayout ( void * obj,

const char * name,

int search_flags,

AVChannelLayout * layout

)

Parameters: [out] layout The returned layout is a copy of the actual value and must be freed with av_channel_layout_uninit() by the caller

Definition at line 1367 of file opt.c.

Referenced by config_output(), and query_formats().

◆ av_opt_get_dict_val()

int av_opt_get_dict_val ( void * obj,

const char * name,

int search_flags,

AVDictionary ** out_val

)

Parameters: [out] out_val The returned dictionary is a copy of the actual value and must be freed with av_dict_free() by the caller

Definition at line 1383 of file opt.c.

Referenced by read_frame_internal().

◆ av_opt_get_array_size()

int av_opt_get_array_size ( void * obj,

const char * name,

int search_flags,

unsigned int * out_val

)

For an array-type option, get the number of elements in the array.

Definition at line 2177 of file opt.c.

Referenced by multiview_setup().

◆ av_opt_get_array()

int av_opt_get_array ( void * obj,

const char * name,

int search_flags,

unsigned int start_elem,

unsigned int nb_elems,

enum AVOptionType out_type,

void * out_val

)

For an array-type option, retrieve the values of one or more array elements.

Parameters

start_elem index of the first array element to retrieve

nb_elems number of array elements to retrieve; start_elem+nb_elems must not be larger than array size as returned by av_opt_get_array_size()

out_type Option type corresponding to the desired output.

 The array elements produced by this function will
 will be as if av_opt_getX() was called for each element,
 where X is specified by out_type. E.g. AV_OPT_TYPE_STRING
 corresponds to av_opt_get().
 Typically this should be the same as the scalarized type of
 the AVOption being retrieved, but certain conversions are
 also possible - the same as those done by the corresponding
 av_opt_get*() function. E.g. any option type can be retrieved
 as a string, numeric types can be retrieved as int64, double,
 or rational, etc.

out_val Array with nb_elems members into which the output will be written. The array type must match the underlying C type as documented for out_type, and be zeroed on entry to this function.

For dynamically allocated types (strings, binary, dicts, etc.), the result is owned and freed by the caller.

Definition at line 2195 of file opt.c.

Referenced by main(), and multiview_setup().

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