Image change detecting apparatus and image change detecting method, image encoding apparatus and information recording medium with image change detecting program recorded readable by computer

摘要

An image change detecting apparatus comprises a differentiating device and a detecting device. The differentiating device differentiates twice a value of an image signal corresponding to a plurality of line-pixels on a single predetermined line, of pixels forming a single static image. The detecting device detects a part sequentially changing in concentration in a partial image including the plurality of line-pixels. The partial image is a part of the static image, when the twice differentiated result is zero.