DPCM CODER AND DPCM DECODER

摘要

PURPOSE:To reduce distortion due to DPCM by revising data used by a prediction means in a decoder and a DPCM coder so as to apply optimum prediction depending on the content of the multiplexed control signal for the vertical blanking period of a video signal. CONSTITUTION:A coder uses a detector 7 so as to detect the content of a control signal multiplexed during the vertical blanking period of a MUSE system video signal and a data used for a prediction means 6 of the DPCM coder 8 is revised by the result of detection to apply optimum prediction and DPCM coding. A decoder uses the DPCM coder to detect a control signal corresponding to the MUSE system video signal subject to DPCM coding and revises the data used by the prediction means of the DPCM decoder depending on the result of detection to apply optimum prediction and decoding into the original signal. Thus, the prediction error is minimized, the high efficient coding is applied to the MUSE signal to apply decoding.