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


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

SYNOPSIS
      #include <tiffio.h>
      int TIFFReadEncodedTile(TIFF* tif, uint tile, uchar* buf, uint size)

DESCRIPTION
      Read the specified tile of data and place size bytes of decompressed
      information in the (user supplied) data buffer.  The actual number of
      bytes of data that were placed in buf is returned; TIFFReadEncodedTile()
      returns -1 if an error was encountered.

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 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), TIFFOpen(3T), TIFFReadRawTile(3T), TIFFReadTile(3T)




















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