bg_input_callbacks_s Struct Reference
[Media input]

Callbacks for input plugins. More...

#include <plugin.h>

Data Fields
void(*	track_changed )(void *data, int track)
	Track changed.
void(*	time_changed )(void *data, gavl_time_t time)
	Time changed.
void(*	duration_changed )(void *data, gavl_time_t duration)
	Duration changed.
void(*	name_changed )(void *data, const char *name)
	Name changed.
void(*	metadata_changed )(void *data, const bg_metadata_t *m)
	Metadata changed.
void(*	buffer_notify )(void *data, float percentage)
	Buffer callback.
int(*	user_pass )(void *data, const char *resource, char **username, char **password)
	Authentication callback.
void(*	aspect_changed )(void *data, int stream, int pixel_width, int pixel_height)
	Aspect ratio change callback.
void *	data
	Application specific data passed as the first argument to all callbacks.

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Detailed Description

Callbacks for input plugins.

Passing the callback structure to the plugin is optional. Futhermore, any of the callback functions is optional (i.e. can be NULL). The plugin might use the callbacks for propagating events.

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Field Documentation

void(* bg_input_callbacks_s::track_changed)(void *data, int track)

Track changed.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	track	The track number starting with 0

This is called by plugins, which support multiple tracks and can switch to a new track without closing/reopening (e.g. the audio-cd player)

void(* bg_input_callbacks_s::time_changed)(void *data, gavl_time_t time)

Time changed.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	time	The current time

This is used only by plugins, which do playback without the player engine (currently only the audio-cd player) to update the displayed time. Normal plugins never call this.

void(* bg_input_callbacks_s::duration_changed)(void *data, gavl_time_t duration)

Duration changed.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	time	The new duration

void(* bg_input_callbacks_s::name_changed)(void *data, const char *name)

Name changed.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	time	The new name

This is for web-radio stations, which send song-names.

void(* bg_input_callbacks_s::metadata_changed)(void *data, const bg_metadata_t *m)

Metadata changed.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	m	The new metadata

This is for web-radio stations, which send metadata for each song.

void(* bg_input_callbacks_s::buffer_notify)(void *data, float percentage)

Buffer callback.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	percentage	The buffer fullness (0.0..1.0)

For network connections, plugins might buffer data. This takes some time, so they notify the API about the progress with this callback.

int(* bg_input_callbacks_s::user_pass)(void *data, const char *resource, char **username, char **password)

Authentication callback.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	resource	Name of the resource (e.g. server name)
	username	Returns the username
	password	Returns the password

Returns:

1 if username and password are available, 0 else.

For sources, which require authentication (like FTP servers), this function is called by the plugin to get username and password. Username and password must be returned in newly allocated strings, which will be freed by the plugin.

void(* bg_input_callbacks_s::aspect_changed)(void *data, int stream, int pixel_width, int pixel_height)

Aspect ratio change callback.

Parameters:

	data	The data member of this bg_input_callbacks_s struct
	stream	Video stream index (starts with 0)
	pixel_width	New pixel width
	pixel_height	New pixel height

Some streams (e.g. DVB) change the pixel aspect ratio on the fly. If the input plugin detects such a change, it should call this callback.

void* bg_input_callbacks_s::data

Application specific data passed as the first argument to all callbacks.

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The documentation for this struct was generated from the following file:

• /tmp/buildd/gmerlin-0.4.0/include/gmerlin/plugin.h