Image signal processor with adaptive noise reduction and an image signal processing method therefor

摘要

An image signal processing device includes a signal processing circuit for executing signal processing for correction and recording on image data representative of an input image. Also, the signal processing circuit executes noise reduction on the individual image data in accordance with image inputting conditions and/or a pixel level. In the signal processing circuit, a threshold generating circuit generates a threshold by taking account of the image inputting conditions and/or a pixel level. During noise reduction, a noise reducing circuit produces a difference in level between the subject pixel data whose noise is to be detected and the mean value of the subject pixel data and pixel data around the subject pixel. The noise reducing circuit then selects either one of the subject pixel data and mean value in accordance with the difference and threshold.