Filtering to Ensure Monotonicity Pavel Mrazek Motivated by processing of the rainbow range finder data which should be increasing monotonically in one direction but are not, we try to develop a filter to ensure monotonicity of the data. The procedure is based on the observation that by convolution with a Gaussian kernel some of the local extrema are removed. The principle of the filter will be presented in illustrative terms of scale-space theory from Lindeberg's book, some experimental results will be shown at the seminar as well.