Image and Video Processing Libraries in Ptolemy II by ... - CiteSeerX

3.2.3 JAICrop
Operations will occasionally enlarge the dimensions of an image. When this is
undesirable, the JAICrop actor can be used to select a rectangular region of
interest that is useful. Other times, only a portion of the image is interesting
in which case, this actor may be used to restrict it to a smaller region.
3.2.4 JAIInvert
The JAIInvert actor inverts every band (subtracts each band from the maximum
value allowed by the internal data type) on the input image. This is often useful
for inverting images that are very dark and would waste toner if printed as is.
3.2.5 JAIPeriodicShift
The JAIPeriodicShift actor takes an image and extends it periodically in all
four directions (with the horizontal and vertical periods being the width and
height respectively). It then shifts the image. The xShift parameter indicates
the amount to shift in the horizontal direction. A positive integer corresponds
to a shift to the right. A negative integer corresponds to a shift to the left. A
value of zero corresponds to no shift at all in the horizontal direction.
The yShift parameter indicates the amount to shift in the vertical direction.
A positive integer corresponds to a shift downwards. A negative integer corre-
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