Abstract: In an arrangement for transforming picture data while using a method of two-dimensional hierarchic sub-band segmentation, particularly a two-dimensional Discrete Wavelet Transformation (2-D DWT), in which pictures, possibly in a plurality of planes, are segmented into sub-bands by means of filtering, a minimal storage space, a minimal bus load and an optimal 2-D DWT transformation ensure that a picture memory (41) is provided in which the data of a picture are stored prior to the start of the first transformation plane and in which the data of a further sub-band to be transformed are stored after the first transformation plane, in which process the data of the picture are partially overwritten, in that the data of a possible further sub-band to be segmented are stored in the picture memory (41) after every further transformation plane, in that a sub-band memory (44) is provided in which, after a transformation process of a plane, the data gained during this transformation of those sub-bands which are no longe

Abstract: A memory-efficient trellis coded quantizer divides consecutive trellis columns into groups or windows each containing the maximum number of columns for which each pair of columns in a window still retains statistical dependence with respect to the states of the column and in relation to any trellis path connecting the two columns. Back searching for code words operates on each individual window, rather than on the overall trellis. Windows are sequentially processed in pairs to derive the code words for the input that has been trellis coded. Required storage is reduced, since trellis and code word storage is required only for the windows currently being processed.

Abstract: In a method of data reduction of a luminance and/or chrominance signal of a digital picture signal by means of fractal image coding, in which method each image of the luminance/chrominance signal is divided into range blocks of n.times.n pixels each, in which a domain block is searched for each range block, which domain block is imageable on the range block with a minimal deviation while using a transformation function, which domain blocks have a larger size than the range blocks, and in which information on the transformation functions is transmitted, from which information the image data are regained at the receiver end in an iterative process, the search is facilitated in that a digital search tree strategy is employed in the search for that domain block which is imageable on a range block with a minimal deviation while using a transformation function.

Abstract: In a method of data reduction of a luminance and/or chrominance signal of a digital picture signal by means of fractal image coding, in which method each image of the luminance/chrominance signal is divided into range blocks of n.times.

Abstract: To achieve an enhanced data reduction, a method of fractal image coding, in which method an image to be encoded is divided into range blocks which do not overlap and jointly cover the image contents completely, in which domain blocks comprising areas of the image contents in their original form or in a transformed form are generated from the image contents, and all areas of the image contents are covered by at least one domain block, for each range block the domain block most similar to the range block being searched, and the addresses of the domain blocks found as the most similar and possibly the transform functions used for their generation being transmitted instead of the data of the range blocks, is characterized in that, in a sequence of images, the fractal image coding performed exclusively within the images is only performed with basic images comprised in the image sequence at selectable time intervals, in that, for intermediate images provided between the basic images, the same range and domain block