1. A method comprising: (a) sampling pixels within a first component region within a digital image using a processing unit, the first component region associated with a first tool impression in a digital image; (b) determining for the first component region a first distribution using the processing unit, the first distribution relating to a pixel property of the sampled pixels within the first component region; (c) computing an adjustment factor using the processing unit, the adjustment factor determined in dependence upon at least the first distribution of the pixel property; (d) receiving a predetermined parameter that is independent of the first distribution of the pixel property; (e) computing an assisted tolerance parameter in dependence upon at least the adjustment factor and the predetermined parameter using the processing unit; (f) sampling pixels within a second component region within the digital image using the processing unit, the second component region associated with a second tool impression in the digital image; (g) determining for the second component region a second distribution using the processing unit, the second distribution relating to the pixel property of the sampled pixels within the second component region; (h) specifying a first edit class of a plurality of edit classes based upon the predetermined parameter and the assisted tolerance parameter, wherein each edit class defines one or more respective subsets of the second distribution; (i) determining for each pixel within the first edit class of the plurality of edit classes a weighting using the processing unit; and (j) collectively editing using the processing unit the subset of sampled pixels within the second component region that correspond to one of the subsets of the distribution defined by the first edit class, the editing being achieved by applying a first edit operation to each pixel that is determined in dependence upon at least the determined weighting for that pixel, the predetermined parameter and the assisted tolerance parameter.