METHOD AND DEVICE FOR RECOGNIZING PATTERN IN FIELD HAVING MULTIVALUE INTENSITY

摘要

PURPOSE: To speed up pattern recognition by recognizing a pattern unless the difference between the relative minimum and maximum values of intensity in areas of fields in corresponding windows of 1st and 2nd submasks having logic high and low units is negative. CONSTITUTION: A reference mask has the 1st and 2nd submasks specifying at which position in the pattern corresponding units having the logic high and low values are generated. Pattern detection includes neither a threshold value process nor a subsequent comparison with the reference mark, but after values at ends of intensity are measured, the sign of the difference between the values at those ends is decided. The decisions on the values at the ends are regarded as decisions on the limit levels of criteria by which the respective submasks are continuously recognized at the time of threshold value processing for the fields. For example, the condition that the difference between the least value among all values in the corresponding window of the 1st submask and the largest value among all values in the corresponding window of the 2nd submask is not negative is imposed on the recognition. Consequently, the pattern recognition can be speeded up.