A method of processing input data using a computing system. The method comprises obtaining association data which relates a kernel in a convolutional neural network to one or more known data patterns; conducting analysis of input data for the convolutional neural network to identify whether a region of input data corresponds to at least one of the one or more known data patterns; and determining whether to process the region of input data with the kernel in the convolutional neural network based on the analysis and the association data.