Tribblix: manual page: TIFFReadEncodedTile.3tiff

TIFFReadEncodedTile(3TIFF) TIFFReadEncodedTile(3TIFF)

NAME

TIFFReadEncodedTile - read and decode a tile of data from an open
TIFF file

SYNOPSIS

#include <tiffio.h>

int TIFFReadEncodedTile(TIFF *tif, ttile_t tile, tdata_t buf, tsize_t
size)

DESCRIPTION

Read the specified tile of data and place up to size bytes of
decompressed information in the (user supplied) data buffer.

NOTES

The value of tile is a ``raw tile number.'' That is, the caller must
take into account whether or not the data are organized in separate
planes (PlanarConfiguration=2). TIFFComputeTile automatically does
this when converting an (x,y,z,sample) coordinate quadruple to a tile
number. To read a full tile of data the data buffer should be at
least as large as the value returned by TIFFTileSize.

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

The actual number of bytes of data that were placed in buf is
returned; TIFFReadEncodedTile returns -1 if an error was encountered.

DIAGNOSTICS