RenderedOp cc = JAI.create("bandselect", pb, JAIContext.noCacheHint);
RenderingHints extenderHints = new RenderingHints(JAI.KEY_BORDER_EXTENDER,
BorderExtender.createInstance(BorderExtender.BORDER_COPY));
pb = new ParameterBlock();
pb.addSource(LuminanceUSMProcessorInstance.process(back));
pb.addSource(Functions.gaussianBlur(back, rendering, op, LuminanceUSMProcessorInstance, radius * scale));
pb.add(amount/100.0);
pb.add((int) threshold);
RenderedOp usm = JAI.create("LCUnSharpMask", pb, extenderHints);
usm.setProperty(JAIContext.PERSISTENT_CACHE_TAG, Boolean.TRUE);