IMAGE ENCRYPTION/DECODING DEVICE, METHOD, AND PROGRAM

摘要

Upon marker addition (encryption), for example, pixels overwritten by a marker are selectively thinned and an image conversion is performed so that the thinning position is moved to the marker addition position. The marker is added to the marker addition position obtained as a result of this. Upon marker deletion (decryption), for example, an image inverse conversion is performed so that respective pixels of the marker are moved to the previous positions before the marker addition. Thus, the respective marker pixels which have been moved are restored and the marker is deleted.