A rendering unit (300) for rendering an output image (102) comprising output pixels, on basis of an input image (100) comprising input pixels and on basis of depth related data elements corresponding to the respective input pixels is disclosed. The rendering unit (300) comprises: a shift computing unit (302) for computing shift values to be applied to the input pixels, on basis of the respective depth related data elements; and an interpolation unit (304) for computing the output pixels on basis of shifting the input pixels with the respective shift values. The shift computing unit (302) is configured to provide an output value as the first one of the shift values, which is substantially equal to zero if the corresponding first one of the input pixels corresponds to overlay, independent of the corresponding depth related data element.