sndfile.h.in

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#define SF_COUNT_MAX		@SF_COUNT_MAX@

/* A pointer to a SF_INFO structure is passed to sf_open_read () and filled in.
** On write, the SF_INFO structure is filled in by the user and passed into
** sf_open_write ().
*/

struct SF_INFO
{	sf_count_t	frames ;		/* Used to be called samples.  Changed to avoid confusion. */
	int			samplerate ;
	int			channels ;
	int			format ;
	int			sections ;
	int			seekable ;
} ;

typedef	struct SF_INFO SF_INFO ;

/* The SF_FORMAT_INFO struct is used to retrieve information about the sound
** file formats libsndfile supports using the sf_command () interface.
**
** Using this interface will allow applications to support new file formats
** and encoding types when libsndfile is upgraded, without requiring
** re-compilation of the application.
**
** Please consult the libsndfile documentation (particularly the information
** on the sf_command () interface) for examples of its use.
*/

typedef struct
{	int			format ;
	const char	*name ;
	const char	*extension ;
} SF_FORMAT_INFO ;

/*
** Enums and typedefs for adding dither on read and write.
** See the html documentation for sf_command(), SFC_SET_DITHER_ON_WRITE
** and SFC_SET_DITHER_ON_READ.
*/

enum
{	SFD_DEFAULT_LEVEL	= 0,
	SFD_CUSTOM_LEVEL	= 0x40000000,

	SFD_NO_DITHER		= 500,
	SFD_WHITE			= 501,
	SFD_TRIANGULAR_PDF	= 502
} ;

typedef struct
{	int			type ;
	double		level ;
	const char	*name ;
} SF_DITHER_INFO ;

/* Struct used to retrieve information about a file embedded within a
** larger file. See SFC_GET_EMBED_FILE_INFO.
*/

typedef struct
{	sf_count_t	offset ;
	sf_count_t	length ;
} SF_EMBED_FILE_INFO ;

/* Struct used to retrieve music sample information from a file.
*/

typedef struct
{	int basenote ;
	int gain ;
	int	sustain_mode ;
	int sustain_start, sustain_end ;
	int release_mode ;
	int release_start, reslease_end ;
} SF_INSTRUMENT ;

/* sustain_mode and release_mode will be one of the following. */

enum
{	SF_LOOP_NONE = 800,
	SF_LOOP_FORWARD,
	SF_LOOP_BACKWARD
} ;

/* Struct used to retrieve loop information from a file.*/
typedef struct
{
	short	time_sig_num ;	/* any positive integer    >0  */
	short	time_sig_den ;	/* any positive power of 2 >0  */
	int		loop_mode ;		/* see SF_LOOP enum            */

	int		num_beats ;		/* this is NOT the amount of quarter notes !!!*/
							/* a full bar of 4/4 is 4 beats */
							/* a full bar of 7/8 is 7 beats */

	float	bpm ;			/* suggestion, as it can be calculated using other fields:*/
							/* file's lenght, file's sampleRate and our time_sig_den*/
							/* -> bpms are always the amount of _quarter notes_ per minute */

	int	root_key ;			/* MIDI note, or -1 for None */
	int future [6] ;
} SF_LOOP_INFO ;

/* Open the specified file for read, write or both. On error, this will
** return a NULL pointer. To find the error number, pass a NULL SNDFILE
** to sf_perror () or sf_error_str ().
** All calls to sf_open() should be matched with a call to sf_close().
*/

SNDFILE* 	sf_open		(const char *path, int mode, SF_INFO *sfinfo) ;

/* Use the existing file descriptor to create a SNDFILE object. If close_desc
** is TRUE, the file descriptor will be closed when sf_close() is called. If
** it is FALSE, the descritor will not be closed.
** When passed a descriptor like this, the library will assume that the start
** of file header is at the current file offset. This allows sound files within
** larger container files to be read and/or written.
** On error, this will return a NULL pointer. To find the error number, pass a
** NULL SNDFILE to sf_perror () or sf_error_str ().
** All calls to sf_open_fd() should be matched with a call to sf_close().

*/

SNDFILE* 	sf_open_fd	(int fd, int mode, SF_INFO *sfinfo, int close_desc) ;

/* sf_error () returns a error number which can be translated to a text
** string using sf_error_number().
*/

int		sf_error		(SNDFILE *sndfile) ;

/* sf_strerror () returns to the caller a pointer to the current error message for
** the given SNDFILE.
*/

const char* sf_strerror (SNDFILE *sndfile) ;

/* sf_error_number () allows the retrieval of the error string for each internal
** error number.
**
*/

const char*	sf_error_number	(int errnum) ;

/* The following three error functions are deprecated but they will remain in the
** library for the forseeable future. The function sf_strerror() should be used
** in their place.
*/

int		sf_perror		(SNDFILE *sndfile) ;
int		sf_error_str	(SNDFILE *sndfile, char* str, size_t len) ;


/* Return TRUE if fields of the SF_INFO struct are a valid combination of values. */

int		sf_command	(SNDFILE *sndfile, int command, void *data, int datasize) ;

/* Return TRUE if fields of the SF_INFO struct are a valid combination of values. */

int		sf_format_check	(const SF_INFO *info) ;

/* Seek within the waveform data chunk of the SNDFILE. sf_seek () uses
** the same values for whence (SEEK_SET, SEEK_CUR and SEEK_END) as
** stdio.h function fseek ().
** An offset of zero with whence set to SEEK_SET will position the
** read / write pointer to the first data sample.
** On success sf_seek returns the current position in (multi-channel)
** samples from the start of the file.
** Please see the libsndfile documentation for moving the read pointer
** separately from the write pointer on files open in mode SFM_RDWR.
** On error all of these functions return -1.
*/

sf_count_t	sf_seek 		(SNDFILE *sndfile, sf_count_t frames, int whence) ;

/* Functions for retrieving and setting string data within sound files.
** Not all file types support this features; AIFF and WAV do. For both
** functions, the str_type parameter must be one of the SF_STR_* values
** defined above.
** On error, sf_set_string() returns non-zero while sf_get_string()
** returns NULL.
*/

int sf_set_string (SNDFILE *sndfile, int str_type, const char* str) ;

const char* sf_get_string (SNDFILE *sndfile, int str_type) ;

/* Functions for reading/writing the waveform data of a sound file.
*/

sf_count_t	sf_read_raw		(SNDFILE *sndfile, void *ptr, sf_count_t bytes) ;
sf_count_t	sf_write_raw 	(SNDFILE *sndfile, void *ptr, sf_count_t bytes) ;

/* Functions for reading and writing the data chunk in terms of frames.
** The number of items actually read/written = frames * number of channels.
**     sf_xxxx_raw		read/writes the raw data bytes from/to the file
**     sf_xxxx_short	passes data in the native short format
**     sf_xxxx_int		passes data in the native int format
**     sf_xxxx_float	passes data in the native float format
**     sf_xxxx_double	passes data in the native double format
** All of these read/write function return number of frames read/written.
*/

sf_count_t	sf_readf_short	(SNDFILE *sndfile, short *ptr, sf_count_t frames) ;
sf_count_t	sf_writef_short	(SNDFILE *sndfile, short *ptr, sf_count_t frames) ;

sf_count_t	sf_readf_int	(SNDFILE *sndfile, int *ptr, sf_count_t frames) ;
sf_count_t	sf_writef_int 	(SNDFILE *sndfile, int *ptr, sf_count_t frames) ;

sf_count_t	sf_readf_float	(SNDFILE *sndfile, float *ptr, sf_count_t frames) ;
sf_count_t	sf_writef_float	(SNDFILE *sndfile, float *ptr, sf_count_t frames) ;

sf_count_t	sf_readf_double		(SNDFILE *sndfile, double *ptr, sf_count_t frames) ;
sf_count_t	sf_writef_double	(SNDFILE *sndfile, double *ptr, sf_count_t frames) ;

/* Functions for reading and writing the data chunk in terms of items.
** Otherwise similar to above.
** All of these read/write function return number of items read/written.
*/

sf_count_t	sf_read_short	(SNDFILE *sndfile, short *ptr, sf_count_t items) ;
sf_count_t	sf_write_short	(SNDFILE *sndfile, short *ptr, sf_count_t items) ;

sf_count_t	sf_read_int		(SNDFILE *sndfile, int *ptr, sf_count_t items) ;
sf_count_t	sf_write_int 	(SNDFILE *sndfile, int *ptr, sf_count_t items) ;

sf_count_t	sf_read_float	(SNDFILE *sndfile, float *ptr, sf_count_t items) ;
sf_count_t	sf_write_float	(SNDFILE *sndfile, float *ptr, sf_count_t items) ;

sf_count_t	sf_read_double	(SNDFILE *sndfile, double *ptr, sf_count_t items) ;
sf_count_t	sf_write_double	(SNDFILE *sndfile, double *ptr, sf_count_t items) ;

/* Close the SNDFILE and clean up all memory allocations associated with this
** file.
** Returns 0 on success, or an error number.
*/

int		sf_close		(SNDFILE *sndfile) ;

#ifdef __cplusplus
}		/* extern "C" */
#endif	/* __cplusplus */

#endif	/* SNDFILE_H */