A/V Converters

Typedefs
typedef struct bg_audio_converter_s	bg_audio_converter_t
	Audio converter.
typedef struct bg_video_converter_s	bg_video_converter_t
	Video converter.
Functions
bg_audio_converter_t *	bg_audio_converter_create (const gavl_audio_options_t *opt)
	Create an audio converter.
int	bg_audio_converter_init (bg_audio_converter_t *cnv, const gavl_audio_format_t *in_format, const gavl_audio_format_t *out_format)
	Initialize an audio converter.
void	bg_audio_converter_connect_input (bg_audio_converter_t *cnv, bg_read_audio_func_t func, void *priv, int stream)
	Set input callback of an audio converter.
int	bg_audio_converter_read (void *priv, gavl_audio_frame_t *frame, int stream, int num_samples)
	Read samples from an audio converter.
void	bg_audio_converter_destroy (bg_audio_converter_t *cnv)
	Destroy an audio converter and free all associated memory.
void	bg_audio_converter_reset (bg_audio_converter_t *cnv)
	Reset an audio converter as if no samples have been processed since initialization.
bg_video_converter_t *	bg_video_converter_create (const gavl_video_options_t *opt)
	Create a video converter.
int	bg_video_converter_init (bg_video_converter_t *cnv, const gavl_video_format_t *in_format, const gavl_video_format_t *out_format)
	Initialize a video converter.
void	bg_video_converter_connect_input (bg_video_converter_t *cnv, bg_read_video_func_t func, void *priv, int stream)
	Set input callback of a video converter.
int	bg_video_converter_read (void *priv, gavl_video_frame_t *frame, int stream)
	Read a video frame from a video converter.
void	bg_video_converter_destroy (bg_video_converter_t *cnv)
	Destroy a video converter and free all associated memory.
void	bg_video_converter_reset (bg_video_converter_t *cnv)
	Reset a video converter as if no samples have been processed since initialization.

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Detailed Description

A/V converters, which can be plugged together with filters and input plugins. These are basically wrappers around the gavl_audio_converter_t and the gavl_video_converter_t with the difference, that they work asynchronous with the advantage, that the video converter can do framerate conversion as well.

The functions for reading A/V frames are compatible with the read functions of input plugins and filters for easy generation of processing pipelines.

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Typedef Documentation

typedef struct bg_audio_converter_s bg_audio_converter_t

Audio converter.

Opaque audio converter structure. You don't want to know, what's inside.

typedef struct bg_video_converter_s bg_video_converter_t

Video converter.

Opaque video converter structure. You don't want to know, what's inside.

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Function Documentation

bg_audio_converter_t* bg_audio_converter_create

(

const gavl_audio_options_t *

opt

)

Create an audio converter.

Parameters:

opt

Audio options

The options should be valid for the whole lifetime of the converter.

int bg_audio_converter_init	(	bg_audio_converter_t *	cnv,
		const gavl_audio_format_t *	in_format,
		const gavl_audio_format_t *	out_format
	)

Initialize an audio converter.

Parameters:

	cnv	An audio converter
	in_format	Input format
	out_format	Output format

Returns:

The number of conversion steps

When this function returns 0 it means, that the converter can be bypassed. It should not be used then until the next initialization, which returns nonzero.

void bg_audio_converter_connect_input	(	bg_audio_converter_t *	cnv,
		bg_read_audio_func_t	func,
		void *	priv,
		int	stream
	)

Set input callback of an audio converter.

Parameters:

	cnv	An audio converter
	func	The function to call
	priv	The private handle to pass to func
	stream	The stream argument to pass to func

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

Read samples from an audio converter.

Parameters:

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

Returns:

The number of samples read. 0 means EOF.

This function can be used as an input callback for audio filters.

void bg_audio_converter_destroy

(

bg_audio_converter_t *

cnv

)

Destroy an audio converter and free all associated memory.

Parameters:

cnv

An audio converter

void bg_audio_converter_reset

(

bg_audio_converter_t *

cnv

)

Reset an audio converter as if no samples have been processed since initialization.

Parameters:

cnv

An audio converter

Reset an audio converter as if no samples have been processed since initialization.

bg_video_converter_t* bg_video_converter_create

(

const gavl_video_options_t *

opt

)

Create a video converter.

Parameters:

opt

Video options

The options should be valid for the whole lifetime of the converter.

int bg_video_converter_init	(	bg_video_converter_t *	cnv,
		const gavl_video_format_t *	in_format,
		const gavl_video_format_t *	out_format
	)

Initialize a video converter.

Parameters:

	cnv	A video converter
	in_format	Input format
	out_format	Output format

Returns:

The number of conversion steps

When this function returns 0 it means, that the converter can be bypassed. It should not be used then until the next initialization, which returns nonzero.

void bg_video_converter_connect_input	(	bg_video_converter_t *	cnv,
		bg_read_video_func_t	func,
		void *	priv,
		int	stream
	)

Set input callback of a video converter.

Parameters:

	cnv	A video converter
	func	The function to call
	priv	The private handle to pass to func
	stream	The stream argument to pass to func

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

Read a video frame from a video converter.

Parameters:

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

Returns:

1 if a frame was read, 0 means EOF.

This function can be used as an input callback for video filters.

void bg_video_converter_destroy

(

bg_video_converter_t *

cnv

)

Destroy a video converter and free all associated memory.

Parameters:

cnv

A video converter

void bg_video_converter_reset

(

bg_video_converter_t *

cnv

)

Reset a video converter as if no samples have been processed since initialization.

Parameters:

cnv

A video converter

Reset a video converter as if no frame has been processed since initialization.