Transformationskodierung beliebig geformter Bildsegmente

摘要

A transformation coding apparatus for a block including a boundary of an object having a certain shape is provided, which includes a transformer (31) for transforming an input block and outputting transformation coefficients, a transformation coefficient selector (32) for selecting and outputting transformation coefficients using the transformation coefficients and the input block, an inverse transformer (33) for inversely transforming the transformation coefficients selected by the transformation coefficient select means and outputting a restored block, an encoder (34) for variable-length-coding the select coefficients selected by the transformation coefficient select means (32) and a repetition controller (32) for calculating a mean square error of the input block and the restored block, comparing the calculated result with a predetermined reference value and determining whether or not coefficient selection is continued. The transformation coding apparatus for a block including a boundary of an object having a certain shape selects a select coefficient which maximizes a ratio of the mean square error DELTA MSE(k) which is decreased according to the added select coefficient (k-th coefficient), with respect to the amount DELTA MSE(k) of variation of the bit quantity which is increased according to the added coefficient (k-th coefficient) when selecting a transformation coefficient, to thereby enhance an original quality of picture and reduce the amount of the necessary bits. <IMAGE>