Tribblix: manual page: TIFFReadTile.3tiff

TIFFReadTile(3TIFF) TIFFReadTile(3TIFF)

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_t x, uint32_t y,
uint32_t 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