Patent ID: 6681051
Filing Date: 2004-01-20
Classification: G06T

Abstract:
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 the picture data, possibly in a plurality of planes, are segmented into sub-bands by means of filtering, characterized in 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; the data of a possible further sub-band to be segmented are stored in the picture memory (41) after every further transformation plane; 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 longer to be segmented in further transformation planes are stored, which data of said sub-band are stored adjacent to each other and in which sub-band data determined in previous transformation planes and possibly already stored in the sub-band memory (44) are not overwritten; in the transformation planes, the data of the picture or the sub-band data stored in the last transformation plane are read from the picture memory, which data are read in blocks (32) comprising a basic block (33) having a size corresponding to the picture section or sub-band to be transformed, and a frame (34) surrounding said picture section and having a width corresponding to half the maximum filter depth of the filters (12, 13, 16, 17, 20, 21) used for the transformation; all basic blocks (33) combined cover all pixels of the picture or sub-band data in the picture memory (41).