Abstract: An apparatus is arranged to perform an equalizing process for equalizing an input signal including a video signal, to obtain a reproduced video signal by performing reproducing processes on the signal equalized and to vary the equalizing characteristic of the equalizing process during a period other than a period during which the reproduced video signal is in process of being obtained. The arrangement enables the apparatus to prevent the reproduced video signal from being affected by changes of the equalizing characteristic and to optimize the equalizing characteristic without impairing the quality of reproduced images.

Abstract: A signal processing apparatus for performing maximum likelihood decoding using one of a partial response PR(1,1) scheme and a partial response PR(1,0,1) scheme, has a maximum likelihood decoding device which includes a comparison circuit for comparing a branch metric difference supplied from an external circuit and a held past metric difference, a holding circuit for holding, as a new metric difference, one of the branch metric difference supplied from the external circuit and the held past metric difference on the basis of a comparison output from the comparison circuit, and a deciding circuit for deciding decoded data on the basis of the comparison output from the comparison circuit.