DATA TRANSFORMATION OF THE INVERSE-FOURIER TYPE

In a method of transforming an input data block (IDB) comprising frequency coefficients (CF) into an output data block (ODB) comprising spatial coefficients, the following steps are carried out. For each frequency coefficient (CF) which is not zero, an individual block of spatial coefficients (IB) is established on the basis of pre-stored data (PSD). The pre-stored data (PSD) pertains to a spatial pattern associated to the frequency coefficient (CF). The thus obtained individual blocks of spatial coefficients (IB) are accumulated to obtain the output data block (ODB). The method allows a transformation of the inverse-fourier type, such as an inverse discrete-cosine transformation for example, to be carried out with relatively little computational effort. The method is particularly suitable for use in video decoding applications.