1. An apparatus for converting discrete values into a transformed representation with integer values, wherein the discrete values have audio and/or image information, comprising: a processor for processing a first block of discrete values by using a first transformation rule to obtain a first block of transformed values; a rounder for rounding the first block of transformed values to obtain a first block of rounded transformed values; a summator for summing the first block of rounded transformed values to a second block of discrete values to obtain a second block of summed values; a processor for processing the second block of summed values by using a second transformation rule to obtain a second block of transformed values; a rounder for rounding the second block of transformed values to obtain a second block of rounded transformed values; and a subtractor for subtracting the second block of rounded transformed values of the first block of discrete values to obtain a block of integer output values of the transformed representation.