 the core code.
    By overriding the code provided an application might add support
    for some esoteric flavor of TIFF that it needs, or it might
    substitute a packing routine that is able to do optimizations
    using application/environment-specific information.
  </p>
  <p>
    The TIFF image viewer found in <b>tools/sgigt.c</b> is an example
    of an application that makes use of the <tt>TIFFRGBAImage</tt>
    support.
  </p>
  <hr>
  <h2 id="scanlines">Scanline-based Image I/O</h2>
  <p>
    The