oggz_seek.h File Reference

Seeking within files. More...

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Typedefs
typedef ogg_int64_t(*	OggzMetric )(OGGZ *oggz, long serialno, ogg_int64_t granulepos, void *user_data)
	This is the signature of a function to correlate Ogg streams.
Functions
ogg_int64_t	oggz_tell_units (OGGZ *oggz)
	Query the current offset in milliseconds, or custom units as specified by a Metric function you have provided.
ogg_int64_t	oggz_seek_units (OGGZ *oggz, ogg_int64_t units, int whence)
	Seek to an offset in milliseconds, or custom units as specified by a Metric function you have provided.
ogg_int64_t	oggz_tell_granulepos (OGGZ *oggz)
	Provide the exact stored granulepos (from the page header) if relevant to the current packet, or a constructed granulepos if the stored granulepos does not belong to this packet, or -1 if this codec does not have support for granulepos interpolation.
oggz_off_t	oggz_tell (OGGZ *oggz)
	Query the file offset in bytes corresponding to the data read.
oggz_off_t	oggz_seek (OGGZ *oggz, oggz_off_t offset, int whence)
	Seek to a specific byte offset.
int	oggz_get_preroll (OGGZ *oggz, long serialno)
	Retrieve the preroll of a logical bitstream.
int	oggz_set_preroll (OGGZ *oggz, long serialno, int preroll)
	Specify the preroll of a logical bitstream.
int	oggz_get_granuleshift (OGGZ *oggz, long serialno)
	Retrieve the granuleshift of a logical bitstream.
int	oggz_set_granuleshift (OGGZ *oggz, long serialno, int granuleshift)
	Specify the granuleshift of a logical bitstream.
int	oggz_get_granulerate (OGGZ *oggz, long serialno, ogg_int64_t *granulerate_n, ogg_int64_t *granulerate_d)
	Retrieve the granulerate of a logical bitstream.
int	oggz_set_granulerate (OGGZ *oggz, long serialno, ogg_int64_t granule_rate_numerator, ogg_int64_t granule_rate_denominator)
	Specify the granulerate of a logical bitstream.
int	oggz_set_metric (OGGZ *oggz, long serialno, OggzMetric metric, void *user_data)
	Set the OggzMetric to use for an OGGZ handle.
int	oggz_set_data_start (OGGZ *oggz, oggz_off_t offset)
	Tell Oggz to remember the given offset as the start of data.
ogg_int64_t	oggz_bounded_seek_set (OGGZ *oggz, ogg_int64_t unit_target, ogg_int64_t offset_begin, ogg_int64_t offset_end)
	Seeks Oggz to time unit_target, but with the bounds of the offset range [offset_begin, offset_end].

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Detailed Description

Seeking within files.

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Function Documentation

ogg_int64_t oggz_bounded_seek_set	(	OGGZ *	oggz,
		ogg_int64_t	unit_target,
		ogg_int64_t	offset_begin,
		ogg_int64_t	offset_end
	)

Seeks Oggz to time unit_target, but with the bounds of the offset range [offset_begin, offset_end].

This is useful when seeking in network streams where only parts of a media are buffered, and retrieving unbuffered parts is expensive.

Parameters:

	oggz	An OGGZ handle previously opened for reading
	unit_target	The seek target, in milliseconds, or custom units
	offset_begin	Start of offset range to seek inside, in bytes
	offset_end	End of offset range to seek inside, in bytes, pass -1 for end of media

Returns:

The new position, in milliseconds or custom units

Return values:

-1

on failure (unit_target is not within range)