tiffreadencodedtile(3)
NAME
TIFFReadEncodedTile - read and decode a tile of data from
an open TIFF file
SYNOPSIS
#include <tiffio.h> int TIFFReadEncodedTile(TIFF* tif, u_long tile, u_char* buf, u_long 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 dif
ferences between the image and the native machine by con
verting 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 automati
cally 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
All error messages are directed to the TIFFError(3) rou
tine.
SEE ALSO
- libtiff(3), TIFFOpen(3), TIFFReadRawTile(3), TIFFRead_
Tile(3)