Abstract: A coding of a block of transformation coefficients wherein a precoder traverses the magnitude bits of a predetermined one of magnitude bit planes in tuples of a plurality of adjacent magnitude bits, and codes predetermined ones of the magnitude bits of the tuples into data words such that a predetermined magnitude bit is coded along with an associated sign bit into one of the data words, or that a predetermined magnitude bit is coded along with any other predetermined magnitude bit of the same tuple, into one of the data words. A data word buffer temporarily stores the data words and an entropy coder codes the data words from the data word buffer into a coded data stream. Alternative coding aspects are also presented. According to one alternative aspect, a running window buffer is filled with status bits while traversing the coefficients.