The invention provides a method of preparing a chemical-mechanical polishing composition for polishing a substrate with at least a first layer and a second layer. The system includes a tunnel source, router and modulator for dividing a transmit data stream having a first bit rate into multiple data streams with each of the multiple data streams having a bit rate which is lower than the first bit rate, transmitting each of the multiple data streams over a plurality of RF channels. When a plurality of point light sources 231 to 239 located behind the hologram 14 are viewed through the hologram 14, a plurality of images are simultaneously and parallel reconstructed in correspondence to the array positions of the plurality of Fourier transform images. For each given image a Probabilistic Boosting Tree is used to detect short line segments of constant length in the image.