Abstract: An error correction system of digital data for use in a digital VTR or a digital TV constituted as parts of a digital processing system, which is provided with an ECC outer encoder, a shuffling means, an inner encoder, a tape, an ECC inner decoder, a de-shuffling means and an ECC outer decoder to perform the double encoding/decoding, comprises a memory address generating circuit for enabling the de-shuffling portion to generate addresses increasing toward the column from the first address of write addresses, a de-shuffling memory circuit for storing data and error flags and a path control circuit for controlling the input/output of data and error flag memories.

Abstract: The image signal band compressing method employs a three-dimensional motion compensating technique, an intraframe and an interframe processes which are alternatively executed. The transfer rate of the intraframe to the interframe is set to 4:1 in a unit of fixed length. The intraframe process is defined such that the present frame image data is compressed in a variable length compressing manner by way of two-dimensional discrete coding transform. The interframe process is defined such that motion data is estimated by comparing the present frame and the preceding frame, the present frame is expected on the basis of the motion data and the difference data between the motion compensated image data and the present frame data.