Image processing apparatus with back porch period sampling and clamping

摘要

An image processing apparatus adds a plurality of input digital chroma image data and input digital luminance image data during a back porch of the input image data and outputs average value data. A subtractor subtracts the average value data, from the input digital chroma image data and input digital luminance image data and outputs data, using a first subtracting method for the chroma image data and a second subtracting method, different from the first subtracting method, for the luminance image data. A memory stores the data output by the subtractor. The input digital chroma image data and the input digital luminance image data are sampled at a frequency an integral number of times as great as a frequency of a subcarrier, and are added.