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Note: This API doc is automatically generated from the current development version that you can get via Subversion or as a daily snapshot from http://mpg123.org/snapshot. There may be differences (additions) compared to the latest stable release. See NEWS.libmpg123 and the overall NEWS file on libmpg123 versions and important changes between them.
Let me emphasize that the policy for libmpg123 is to always stay backwards compatible -- only additions are planned (and it's not yet planned to change the plans;-).

mpg123 advanced parameter API

Typedefs
typedef struct mpg123_pars_struct	mpg123_pars
Functions
mpg123_handle *	mpg123_parnew (mpg123_pars *mp, const char *decoder, int *error)
mpg123_pars *	mpg123_new_pars (int *error)
void	mpg123_delete_pars (mpg123_pars *mp)
int	mpg123_fmt_none (mpg123_pars *mp)
int	mpg123_fmt_all (mpg123_pars *mp)
int	mpg123_fmt (mpg123_pars *mh, long rate, int channels, int encodings)
int	mpg123_fmt_support (mpg123_pars *mh, long rate, int encoding)
int	mpg123_par (mpg123_pars *mp, enum mpg123_parms type, long value, double fvalue)
int	mpg123_getpar (mpg123_pars *mp, enum mpg123_parms type, long *val, double *fval)

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Detailed Description

Direct access to a parameter set without full handle around it. Possible uses:

• Influence behaviour of library _during_ initialization of handle (MPG123_VERBOSE).
• Use one set of parameters for multiple handles.

The functions for handling mpg123_pars (mpg123_par() and mpg123_fmt() family) directly return a fully qualified mpg123 error code, the ones operating on full handles normally MPG123_OK or MPG123_ERR, storing the specific error code itseld inside the handle.

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Typedef Documentation

typedef struct mpg123_pars_struct mpg123_pars

Opaque structure for the libmpg123 decoder parameters.

Definition at line 797 of file mpg123.h.

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Function Documentation

mpg123_handle* mpg123_parnew	(	mpg123_pars *	mp,
		const char *	decoder,
		int *	error
	)

Create a handle with preset parameters.

mpg123_pars* mpg123_new_pars

(

int *

error

)

Allocate memory for and return a pointer to a new mpg123_pars

void mpg123_delete_pars

(

mpg123_pars *

mp

)

Delete and free up memory used by a mpg123_pars data structure

int mpg123_fmt_none

(

mpg123_pars *

mp

)

Configure mpg123 parameters to accept no output format at all, use before specifying supported formats with mpg123_format

int mpg123_fmt_all

(

mpg123_pars *

mp

)

Configure mpg123 parameters to accept all formats (also any custom rate you may set) -- this is default.

int mpg123_fmt	(	mpg123_pars *	mh,
		long	rate,
		int	channels,
		int	encodings
	)

Set the audio format support of a mpg123_pars in detail:

Parameters:

	rate	The sample rate value (in Hertz).
	channels	A combination of MPG123_STEREO and MPG123_MONO.
	encodings	A combination of accepted encodings for rate and channels, p.ex MPG123_ENC_SIGNED16|MPG123_ENC_ULAW_8 (or 0 for no support).

Returns:

0 on success, -1 if there was an error. /

int mpg123_fmt_support	(	mpg123_pars *	mh,
		long	rate,
		int	encoding
	)

Check to see if a specific format at a specific rate is supported by mpg123_pars.

Returns:

0 for no support (that includes invalid parameters), MPG123_STEREO, MPG123_MONO or MPG123_STEREO|MPG123_MONO.

int mpg123_par	(	mpg123_pars *	mp,
		enum mpg123_parms	type,
		long	value,
		double	fvalue
	)

Set a specific parameter, for a specific mpg123_pars, using a parameter type key chosen from the mpg123_parms enumeration, to the specified value.

int mpg123_getpar	(	mpg123_pars *	mp,
		enum mpg123_parms	type,
		long *	val,
		double *	fval
	)

Get a specific parameter, for a specific mpg123_pars. See the mpg123_parms enumeration for a list of available parameters.

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