Patent ID: 7106346

Claim:
A signal processing apparatus for adjusting levels of signals arranged consecutively, the apparatus comprising: first designating means for sequentially designating each of said signals as a target signal; second designating means for designating a plurality of neighboring signals from among said signals on the basis of the target signal designated by the first designating means; calculating means for calculating differences between the target signal and the plurality of neighboring signals and for calculating a smoothing signal by obtaining a weighted average of the target signal and the plurality of neighboring signals in accordance with results of comparison between the differences and a first threshold; determining means for calculating the differences between the target signal and the plurality of neighboring signals and for determining whether or not a fine edge exists near the target signal in accordance with results of comparison between the differences and a second threshold, which is smaller than the first threshold; and selecting means for selecting one of the smoothing signal and the target signal in accordance with a result determined by the determining means.