Abstract: An apparatus for storing high definition image signals capable of processing high definition image signals and low definition image signals using the same apparatus. A storage medium is provided with an interface of low definition image signals. High definition image signals are compressed, transformed into a format according to the specifications of the interface of low definition image signals and are then stored in the storage medium. The compressed image signals taken out from the storage medium are subjected to the format reverse transform for expansion to restore the original high definition image signals. The format-transformed compressed high definition image signals and the compressed high definition image signals taken out from the storage medium are transmitted over a transmission medium via low definition image interface and are, as required, stored in the storage medium or put to other processings, and are then expanded to restore the original high definition image signals.

Abstract: An interpolation circuit, in which a digital signal produced by sampling and quantizing an analog information sequentially is encoded so that, in case a certain one of the encoded sample data is erroneous, a correct data in place of the erroneous sample data is prepared as an interpolation data by interpolating other correct sample data. The interpolation circuit includes: a first extrapolation circuit for generating a first extrapolation data by extrapolating two sample data preceding the erroneous sample data to the position of said erroneous sample data, a second extrapolation circuit for generating a second extrapolation data by extrapolating the two sample data succeeding the erroneous sample data to the position of the erroneous sample data, and an averaging circuit for generating the interpolation data by arithmetically averaging the first and second extrapolation data.