NAME¶
TIFFReadTile - read and decode a tile of data from an open
TIFF
file
SYNOPSIS¶
#include <tiffio.h>
tsize_t TIFFReadTile(TIFF *tif, tdata_t buf,
uint32 x, uint32 y, uint32 z,
tsample_t sample)
DESCRIPTION¶
Return the data for the tile
containing the specified coordinates. The
data placed in
buf are returned decompressed and, typically, in the
native byte- and bit-ordering, but are otherwise packed (see further below).
The buffer must be large enough to hold an entire tile of data. Applications
should call the routine
TIFFTileSize to find out the size (in bytes) of
a tile buffer. The
x and
y parameters are always used by
TIFFReadTile. The
z parameter is used if the image is deeper
than 1 slice (
ImageDepth>1). The
sample parameter is used
only if data are organized in separate planes (
PlanarConfiguration=2).
NOTES¶
The library attempts to hide bit- and byte-ordering differences between the
image and the native machine by converting data to the native machine order.
Bit reversal is done if the
FillOrder tag is opposite to the native
machine bit order. 16- and 32-bit samples are automatically byte-swapped if
the file was written with a byte order opposite to the native machine byte
order,
RETURN VALUES¶
TIFFReadTile returns -1 if it detects an error; otherwise the number of
bytes in the decoded tile is returned.
DIAGNOSTICS¶
All error messages are directed to the
TIFFError(3TIFF) routine.
SEE ALSO¶
TIFFCheckTile(3TIFF),
TIFFComputeTile(3TIFF),
TIFFOpen(3TIFF),
TIFFReadEncodedTile(3TIFF),
TIFFReadRawTile(3TIFF),
libtiff(3TIFF)
Libtiff library home page:
http://www.remotesensing.org/libtiff/