Abstract: Embodiments of the invention include a method and apparatus for downscaling a digital matrix image by selected ratios. According to embodiments, the value of each output pixel of the output matrix is calculated from the values of the input pixels. The output pixels (k,l) are processed in such a way that the weighted sum of the values of the pixels (i,j) of the matrix image in the area of each output pixel (k,l) is formed, the weighting coefficient being the dimension share of the pixel (i,j) in the area of the output pixel (k,l) and each weighted sum is corrected by a scaling factor (f×M2/M1×N2/N1).

Abstract: The invention relates to an electronic device, which includes data-processing means and a memory, for performing processing on image data on the basis of blocks. The image data is arranged to be coded into unit blocks (B, MB) arranged in a preset manner, from which a processing area (PA) according to the settings can be formed from the data of one or more blocks (B, MB). For processing, data on the processing area (PA) is arranged in the memory, as well as, in a preset manner, data on the surroundings areas (EA1, EA2, EA4) of the processing area (PA), for processing the edge areas of the processing area (PA). Part of the processing area (PA1, PA2) is arranged to be formed from one or more unit blocks (MBP1-MBP3, BP1-BP5) that has been previously coded and of an area that has possibly already been at least partly processed. In addition, the invention also relates to a method and program product.