Audio converter
[Audio]

Audio format converter. More...


Typedefs

typedef struct
gavl_audio_converter_s 
gavl_audio_converter_t
 Opaque audio converter structure.

Functions

gavl_audio_converter_tgavl_audio_converter_create ()
 Creates an audio converter.
void gavl_audio_converter_destroy (gavl_audio_converter_t *cnv)
 Destroys an audio converter and frees all associated memory.
gavl_audio_options_tgavl_audio_converter_get_options (gavl_audio_converter_t *cnv)
 gets options of an audio converter
int gavl_audio_converter_init (gavl_audio_converter_t *cnv, const gavl_audio_format_t *input_format, const gavl_audio_format_t *output_format)
 Initialize an audio converter.
int gavl_audio_converter_reinit (gavl_audio_converter_t *cnv)
 Reinitialize an audio converter.
void gavl_audio_convert (gavl_audio_converter_t *cnv, const gavl_audio_frame_t *input_frame, gavl_audio_frame_t *output_frame)
 Convert audio.


Detailed Description

Audio format converter.

This is a generic converter, which converts audio frames from one arbitrary format to another. It does:

Quality levels below 3 mainly result if poor but fast resampling methods. Quality levels above 3 will enable high quality resampling methods, dithering and floating point mixing.

Create an audio converter with gavl_audio_converter_create. If you want to configure it, get the options pointer with gavl_audio_converter_get_options and change the options (See Audio conversion options). Call gavl_audio_converter_init to initialize the converter for the input and output formats. Audio frames are then converted with gavl_audio_convert.

When you are done, you can either reinitialize the converter or destroy it with gavl_audio_converter_destroy.


Typedef Documentation

typedef struct gavl_audio_converter_s gavl_audio_converter_t

Opaque audio converter structure.

You don't want to know what's inside.


Function Documentation

gavl_audio_converter_t* gavl_audio_converter_create (  ) 

Creates an audio converter.

Returns:
A newly allocated audio converter

void gavl_audio_converter_destroy ( gavl_audio_converter_t cnv  ) 

Destroys an audio converter and frees all associated memory.

Parameters:
cnv An audio converter

gavl_audio_options_t* gavl_audio_converter_get_options ( gavl_audio_converter_t cnv  ) 

gets options of an audio converter

Parameters:
cnv An audio converter
After you called this, you can use the gavl_audio_options_set_*() functions to change the options. Options will become valid with the next call to gavl_audio_converter_init or gavl_audio_converter_reinit

int gavl_audio_converter_init ( gavl_audio_converter_t cnv,
const gavl_audio_format_t input_format,
const gavl_audio_format_t output_format 
)

Initialize an audio converter.

Parameters:
cnv An audio converter
input_format Input format
output_format Output format
Returns:
The number of single conversion steps necessary to perform the conversion. It may be 0, in this case you don't need the converter and can pass the audio frames directly. If something goes wrong (should never happen), -1 is returned.
This function can be called multiple times with one instance

int gavl_audio_converter_reinit ( gavl_audio_converter_t cnv  ) 

Reinitialize an audio converter.

Parameters:
cnv An audio converter
Returns:
The number of single conversion steps necessary to perform the conversion. It may be 0, in this case you don't need the converter and can pass the audio frames directly. If something goes wrong (should never happen), -1 is returned.
This function can be called if the input and output formats didn't change but the options did.

void gavl_audio_convert ( gavl_audio_converter_t cnv,
const gavl_audio_frame_t input_frame,
gavl_audio_frame_t output_frame 
)

Convert audio.

Parameters:
cnv An audio converter
input_frame Input frame
output_frame Output frame
Be careful when resampling: gavl will assume, that your output frame is big enough. Minimum size is input_frame_size * output_samplerate / input_samplerate + 10


Generated on Thu Oct 16 13:03:17 2008 for gavl by  doxygen 1.5.7.1