Filter chains

Chains of A/V filters. More...

Typedefs
typedef struct bg_audio_filter_chain_s	bg_audio_filter_chain_t
	Audio filter chain.
typedef struct bg_video_filter_chain_s	bg_video_filter_chain_t
	Video filter chain.
Functions
bg_audio_filter_chain_t *	bg_audio_filter_chain_create (const bg_gavl_audio_options_t *opt, bg_plugin_registry_t *plugin_reg)
	Create an audio filter chain.
const bg_parameter_info_t *	bg_audio_filter_chain_get_parameters (bg_audio_filter_chain_t *ch)
	Return parameters.
void	bg_audio_filter_chain_set_parameter (void *data, const char *name, const bg_parameter_value_t *val)
	Set a parameter for an audio chain.
int	bg_audio_filter_chain_need_rebuild (bg_audio_filter_chain_t *ch)
	Check if an audio filter chain needs to be rebuilt.
int	bg_audio_filter_chain_need_restart (bg_audio_filter_chain_t *ch)
	Check if an audio filter chain needs to be restarted.
void	bg_audio_filter_chain_connect_input (bg_audio_filter_chain_t *ch, bg_read_audio_func_t func, void *priv, int stream)
	Set input callback of an audio filter chain.
int	bg_audio_filter_chain_init (bg_audio_filter_chain_t *ch, const gavl_audio_format_t *in_format, gavl_audio_format_t *out_format)
	Initialize an audio filter chain.
void	bg_audio_filter_chain_set_input_format (bg_audio_filter_chain_t *ch, const gavl_audio_format_t *in_format)
	Change the input format of an audio filter chain.
int	bg_audio_filter_chain_set_out_format (bg_audio_filter_chain_t *ch, const gavl_audio_format_t *out_format)
	Set output format of an audio filter chain.
int	bg_audio_filter_chain_read (void *priv, gavl_audio_frame_t *frame, int stream, int num_samples)
	Read a audio samples from an audio filter chain.
void	bg_audio_filter_chain_destroy (bg_audio_filter_chain_t *ch)
	Destroy an audio filter chain.
void	bg_audio_filter_chain_lock (bg_audio_filter_chain_t *ch)
	Lock an audio filter chain.
void	bg_audio_filter_chain_unlock (bg_audio_filter_chain_t *ch)
	Unlock an audio filter chain.
void	bg_audio_filter_chain_reset (bg_audio_filter_chain_t *ch)
	Reset an audio filter chain.
bg_video_filter_chain_t *	bg_video_filter_chain_create (const bg_gavl_video_options_t *opt, bg_plugin_registry_t *plugin_reg)
	Create a video filter chain.
const bg_parameter_info_t *	bg_video_filter_chain_get_parameters (bg_video_filter_chain_t *ch)
	Return parameters.
void	bg_video_filter_chain_set_parameter (void *data, const char *name, const bg_parameter_value_t *val)
	Set a parameter for a video chain.
int	bg_video_filter_chain_need_rebuild (bg_video_filter_chain_t *ch)
	Check if a video filter chain needs to be rebuilt.
int	bg_video_filter_chain_need_restart (bg_video_filter_chain_t *ch)
	Check if a video filter chain needs to be restarted.
void	bg_video_filter_chain_connect_input (bg_video_filter_chain_t *ch, bg_read_video_func_t func, void *priv, int stream)
	Set input callback of a video filter chain.
int	bg_video_filter_chain_init (bg_video_filter_chain_t *ch, const gavl_video_format_t *in_format, gavl_video_format_t *out_format)
	Initialize a video filter chain.
void	bg_video_filter_chain_set_input_format (bg_video_filter_chain_t *ch, const gavl_video_format_t *in_format)
	Change the input format of a video filter chain.
int	bg_video_filter_chain_set_out_format (bg_video_filter_chain_t *ch, const gavl_video_format_t *out_format)
	Set output format of a video filter chain.
int	bg_video_filter_chain_read (void *priv, gavl_video_frame_t *frame, int stream)
	Read a video frame from a video filter chain.
void	bg_video_filter_chain_destroy (bg_video_filter_chain_t *ch)
	Destroy a video filter chain.
void	bg_video_filter_chain_lock (bg_video_filter_chain_t *ch)
	Lock a video filter chain.
void	bg_video_filter_chain_unlock (bg_video_filter_chain_t *ch)
	Unlock a video filter chain.
void	bg_video_filter_chain_reset (bg_video_filter_chain_t *ch)
	Reset a video filter chain.

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Detailed Description

Chains of A/V filters.

---

Typedef Documentation

typedef struct bg_audio_filter_chain_s bg_audio_filter_chain_t

Audio filter chain.

Opaque handle for an audio filter chain. You don't want to know, what's inside.

typedef struct bg_video_filter_chain_s bg_video_filter_chain_t

Video filter chain.

Opaque handle for a video filter chain. You don't want to know, what's inside.

---

Function Documentation

bg_audio_filter_chain_t* bg_audio_filter_chain_create	(	const bg_gavl_audio_options_t *	opt,
		bg_plugin_registry_t *	plugin_reg
	)

Create an audio filter chain.

Parameters:

opt	Conversion options
plugin_reg	A plugin registry

The conversion options should be valid for the whole lifetime of the filter chain.

const bg_parameter_info_t* bg_audio_filter_chain_get_parameters

(

bg_audio_filter_chain_t *

ch

)

Return parameters.

Parameters:

ch	An audio filter chain

Returns:

A NULL terminated array of parameter descriptions

Usually, there will be a parameter of type BG_PARAMETER_MULTI_CHAIN, which includes all installed filters and their respective parameters.

void bg_audio_filter_chain_set_parameter	(	void *	data,
		const char *	name,
		const bg_parameter_value_t *	val
	)

Set a parameter for an audio chain.

Parameters:

data	An audio converter as void*
name	Name
val	Value

In some cases the filter chain must be rebuilt after setting a parameter. The application should therefore call bg_audio_filter_chain_need_rebuild and call bg_audio_filter_chain_init if necessary.

int bg_audio_filter_chain_need_rebuild

(

bg_audio_filter_chain_t *

ch

)

Check if an audio filter chain needs to be rebuilt.

Parameters:

ch	An audio filter chain

Returns:

1 if the chain must be rebuilt, 0 else

If this returns true, you should call bg_audio_filter_chain_rebuild or bg_audio_filter_chain_init. It's usually used after bg_audio_filter_chain_set_parameter.

int bg_audio_filter_chain_need_restart

(

bg_audio_filter_chain_t *

ch

)

Check if an audio filter chain needs to be restarted.

Parameters:

ch	An audio filter chain

Returns:

1 if the chain must be restarted, 0 else

If this returns true, you should call bg_audio_filter_chain_init. It's usually used after bg_audio_filter_chain_set_parameter.

void bg_audio_filter_chain_connect_input	(	bg_audio_filter_chain_t *	ch,
		bg_read_audio_func_t	func,
		void *	priv,
		int	stream
	)

Set input callback of an audio filter chain.

Parameters:

ch	An audio filter chain
func	The function to call
priv	The private handle to pass to func
stream	The stream argument to pass to func

This function must be called *before* bg_audio_filter_chain_init.

int bg_audio_filter_chain_init	(	bg_audio_filter_chain_t *	ch,
		const gavl_audio_format_t *	in_format,
		gavl_audio_format_t *	out_format
	)

Initialize an audio filter chain.

Parameters:

ch	An audio filter chain
in_format	Input format
out_format	Returns the output format

void bg_audio_filter_chain_set_input_format	(	bg_audio_filter_chain_t *	ch,
		const gavl_audio_format_t *	in_format
	)

Change the input format of an audio filter chain.

Parameters:

ch	An audio filter chain
in_format	New input format

int bg_audio_filter_chain_set_out_format	(	bg_audio_filter_chain_t *	ch,
		const gavl_audio_format_t *	out_format
	)

Set output format of an audio filter chain.

Parameters:

ch	An audio filter chain
out_format	Output format

Returns:

The number of conversion steps

This function initializes a final audio converter at the output for delivering the desired format.

int bg_audio_filter_chain_read	(	void *	priv,
		gavl_audio_frame_t *	frame,
		int	stream,
		int	num_samples
	)

Read a audio samples from an audio filter chain.

Parameters:

priv	An audio filter chain
frame	An audio frame
stream	Stream number (must be 0)
num_samples	Number of samples to read

Returns:

Number of samples read, 0 means EOF.

void bg_audio_filter_chain_destroy

(

bg_audio_filter_chain_t *

ch

)

Destroy an audio filter chain.

Parameters:

ch	An audio filter chain

void bg_audio_filter_chain_lock

(

bg_audio_filter_chain_t *

ch

)

Lock an audio filter chain.

Parameters:

ch	An audio filter chain

In multithreaded enviroments, you must lock the chain for calls to bg_audio_filter_chain_set_parameter and bg_audio_filter_chain_read.

void bg_audio_filter_chain_unlock

(

bg_audio_filter_chain_t *

ch

)

Unlock an audio filter chain.

Parameters:

ch	An audio filter chain

In multithreaded enviroments, you must lock the chain for calls to bg_audio_filter_chain_set_parameter and bg_audio_filter_chain_read.

void bg_audio_filter_chain_reset

(

bg_audio_filter_chain_t *

ch

)

Reset an audio filter chain.

Parameters:

ch	An audio filter chain

Set the internal state as if no sample has been processed since last init

bg_video_filter_chain_t* bg_video_filter_chain_create	(	const bg_gavl_video_options_t *	opt,
		bg_plugin_registry_t *	plugin_reg
	)

Create a video filter chain.

Parameters:

opt	Conversion options
plugin_reg	A plugin registry

The conversion options should be valid for the whole lifetime of the filter chain.

const bg_parameter_info_t* bg_video_filter_chain_get_parameters

(

bg_video_filter_chain_t *

ch

)

Return parameters.

Parameters:

ch	A video filter chain

Returns:

A NULL terminated array of parameter descriptions

Usually, there will be a parameter of type BG_PARAMETER_MULTI_CHAIN, which includes all installed filters and their respective parameters.

void bg_video_filter_chain_set_parameter	(	void *	data,
		const char *	name,
		const bg_parameter_value_t *	val
	)

Set a parameter for a video chain.

Parameters:

data	A video converter as void*
name	Name
val	Value

In some cases the filter chain must be rebuilt after setting a parameter. The application should therefore call bg_video_filter_chain_need_rebuild and call bg_video_filter_chain_init if necessary.

int bg_video_filter_chain_need_rebuild

(

bg_video_filter_chain_t *

ch

)

Check if a video filter chain needs to be rebuilt.

Parameters:

ch	A video filter chain

Returns:

1 if the chain must be rebuilt, 0 else

If this returns true, you should call bg_video_filter_chain_init. It's usually used after bg_video_filter_chain_set_parameter.

int bg_video_filter_chain_need_restart

(

bg_video_filter_chain_t *

ch

)

Check if a video filter chain needs to be restarted.

Parameters:

ch	A video filter chain

Returns:

1 if the chain must be restarted, 0 else

If this returns true, you should call bg_video_filter_chain_init. It's usually used after bg_video_filter_chain_set_parameter.

void bg_video_filter_chain_connect_input	(	bg_video_filter_chain_t *	ch,
		bg_read_video_func_t	func,
		void *	priv,
		int	stream
	)

Set input callback of a video filter chain.

Parameters:

ch	A video filter chain
func	The function to call
priv	The private handle to pass to func
stream	The stream argument to pass to func

This function must be called *before* bg_video_filter_chain_init.

int bg_video_filter_chain_init	(	bg_video_filter_chain_t *	ch,
		const gavl_video_format_t *	in_format,
		gavl_video_format_t *	out_format
	)

Initialize a video filter chain.

Parameters:

ch	A video filter chain
in_format	Input format
out_format	Returns the output format

void bg_video_filter_chain_set_input_format	(	bg_video_filter_chain_t *	ch,
		const gavl_video_format_t *	in_format
	)

Change the input format of a video filter chain.

Parameters:

ch	An video filter chain
in_format	New input format

int bg_video_filter_chain_set_out_format	(	bg_video_filter_chain_t *	ch,
		const gavl_video_format_t *	out_format
	)

Set output format of a video filter chain.

Parameters:

ch	A video filter chain
out_format	Output format

This function initializes a final video converter at the output for delivering the desired format.

int bg_video_filter_chain_read	(	void *	priv,
		gavl_video_frame_t *	frame,
		int	stream
	)

Read a video frame from a video filter chain.

Parameters:

priv	A video filter chain
frame	A video frame
stream	Stream number (must be 0)

Returns:

1 if a frame was read, 0 means EOF.

void bg_video_filter_chain_destroy

(

bg_video_filter_chain_t *

ch

)

Destroy a video filter chain.

Parameters:

ch	A video filter chain

void bg_video_filter_chain_lock

(

bg_video_filter_chain_t *

ch

)

Lock a video filter chain.

Parameters:

ch	A video filter chain

In multithreaded enviroments, you must lock the chain for calls to bg_video_filter_chain_set_parameter and bg_video_filter_chain_read.

void bg_video_filter_chain_unlock

(

bg_video_filter_chain_t *

ch

)

Unlock a video filter chain.

Parameters:

ch	A video filter chain

In multithreaded enviroments, you must lock the chain for calls to bg_video_filter_chain_set_parameter and bg_video_filter_chain_read.

void bg_video_filter_chain_reset

(

bg_video_filter_chain_t *

ch

)

Reset a video filter chain.

Parameters:

ch	A video filter chain

Set the internal state as if no sample has been processed since last init