| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a data compression apparatus performing new and preferable reversible compression processing applicable to compression of CT data. <P>SOLUTION: A data compression apparatus is provided with: a two-dimensional difference creating section for obtaining a two-dimensional difference based on a plurality of numerical values adjacent to, in a plurality of directions when seen on an image, numerical values constituting the data to be compressed so as to create new data to be compressed; an offset section for offsetting each of the numerical values constituting new data to be compressed generated by the two-dimensional difference creating section by a predetermined value; a divisional section for dividing every numerical value of the data to be compressed which is subjected to the offset into a high-order bit portion and a low-order bit portion; a high-order data compression section for applying reversible compression processing to the high-order data consisting of the high-order bit portion; and a low-order data compression section for applying reversible compression processing to the low-order data consisting of the low-order bit portion. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
