f the same ColorModel
 is used for every call to setPixels, otherwise the pixels are
 accumulated in the default RGB ColorModel.  If the forceRGB
 parameter is true, then the pixels will be accumulated in the
 default RGB ColorModel anywya.  A buffer is allocated by the
 PixelGrabber to hold the pixels in either case.  If (w < 0) or
 (h < 0), then they will default to the remaining width and
 height of the source data when that information is delivered.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>img</CODE> - 