PURPOSE: To reduce generating frequency of signal errors due to a pttern peak shift, etc., by converting a pattern into such a pattern that the prescribed number or more of "1" or "0" will not continue in terms of 8-8 mapping table for decreasing a DC component at the time of magnetic recording.
CONSTITUTION: First, a pattern of n max=6 (nr=3; ns=3) is preferentially used as a 8-8 mapping table for a Y signal, and a number of quantized levels 196 are secured. For a pattern of remaining four levels, a pattern having six numbers of "1" among n max=7 or 8 bits is selectively used and storedin tables 8, 9 and 10. Since the necessary number of quantized levels is 224 for a mapping table for signals C1 and C2, n max=8 (nr=ns≤4) is adopted and stored in the tables 8, 9 and 10. Thus the Y signal table is satisfied with n max=6 at approximately a quantized level.
MITA SEIICHI
MICHIKAWA YUUICHI
IZUMIDA MORIJI
KATAYAMA HITOSHI
ROKUTA MORIHITO
KANEDA HIDEHIRO
HITACHI ELECTRONICS
| JPS58195349A | 1983-11-14 | |||
| JPS5831644A | 1983-02-24 | |||
| JPS59218068A | 1984-12-08 |