TIFFReadTile(3T)         UNIX System V(June 18, 1991)          TIFFReadTile(3T)


NAME
      TIFFReadTile - read and decode a tile from an open TIFF file

SYNOPSIS
      #include <tiffio.h>
      int TIFFReadTile(TIFF* tif, uchar* buf, ulong x, ulong y, ulong z,
      uint 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 TIFFTileeSize() 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).  TIFFReadTile
      returns -1 if it detects an error; otherwise 1 is returned.

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 always done if the FillOrder tag is opposite to
      the native machine bit order.  Byte swapping of 16- and 32-bit samples is
      automatically done when Compression=1 (``no compression''), but otherwise
      is left to the decompression algorithms (which should generate
      decompressed data in the native byte ordering of the machine).

DIAGNOSTICS
      All error messages are directed to the TIFFError(3T) routine.

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



















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