In a signal processor, a sampling arrangement samples at least a first signal and a second signal so as to obtain sampled first signal and a sampled second signal, respectively. The transmitter includes a high-efficiency FM laser connected to a FM discriminator. In addition, the method may include merging other regions of the plurality of regions without considering the scoring matrix when the other regions are smaller than a threshold number of pixels and automatically removing artifacts and noise from the raster image based on the threshold number of pixels.