scanlines from the beginning
			   of a strip (row will always be &gt;0 and &lt;rows/strip */
fooCleanup(tif)		/* called when compression scheme is replaced by user */
</PRE>

<P>
Note that the encoding and decoding variants are only needed when
a compression algorithm is dependent on the structure of the data.
For example, Group 3 2D encoding and decoding maintains a reference
scanline.  The sample parameter identifies which sample is to be
encoded or decoded if the image is organized with <TT>PlanarConfig