TIFFReadTile

TIFFReadTile(3T)                                              TIFFReadTile(3T)



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 automati-
       cally 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(3T) routine.

SEE ALSO
       libtiff(3T),  TIFFCheckTile(3T),   TIFFComputeTile(3T),   TIFFOpen(3T),
       TIFFReadEncodedTile(3T), TIFFReadRawTile(3T)



                               December 16, 1991              TIFFReadTile(3T)