PICTURE CODER AND PICTURE DECODER

摘要

PURPOSE:To reduce the transmission cost by reducing a transmission data quantity for recording or transmission of a picture signal and to prevent picture quality deterioration at pattern changeover. CONSTITUTION:A coder 1 applying in-pattern/inter-pattern adaptive coding to a coded picture signal (a) is provided. A counter 2 measures number of patterns in time series. Based on the count, a refresh signal generator 11 outputs a refresh command signal (i) switching periodically a pattern into an in-pattern coding. At the input of a refresh command signal (i), the coder 1 applies in- pattern coding to the entire pattern and applies in-pattern/inter-pattern adaptive coding in other cases and gives a coded signal (b) to a transmitter 3. Then the transmitter 3 adds an error correction code to an input signal to execute modulation processing and sends it to a picture decoder. On the other hand, the transmitter 12 sends simultaneously an edit point command signal (h).