1. A method of processing a mammogram, comprising: obtaining a lower image quality input mammogram from a system; acquiring plural image patches from the input mammogram where each patch comprises a respective group of pixels; entering the image patches into a computer-implemented, trainable regression model as input and obtaining from the model output pixel values corresponding to respective image patches using a process that derives an output pixel from each respective input patch; wherein the trainable regression model has been trained through computer processing to convert known lower image quality mammograms to known higher image quality mammograms; and arranging the output pixel values from the regression model into a desired output mammogram of higher image quality than the input mammogram; wherein the output pixels of the desired output mammogram are spatially arranged in relation to the spatial arrangement of the image patches of the input mammogram.