For performing high-efficient coding, a coding system comprises: (a) input means for inputting an input signal (201) to be encoded; (b) a field memory (28,29) for storing the input signal by dividing said signal into a plurality of fields such as the odd field and even field; (c) predictive signal output means for outputting a plurality of predictive signals predicting the change of input signal corresponded to each signal stored in said field memory; (d) a selector (21) for selecting a predictive signal from the predictive signals provided by said predictive signal output means; and (e) coding means (24) for encoding the input signal using the relationship between said predictive signal selected by said selector and the input signal from said input means.