Printing gray-tone image as pseudo half-tone image - comparing half-tone values with threshold matrix values to generate outputs to printer unit to vary intensity

摘要

The printing of a gray tone image as a pseudo half tone image is achieved using a matrix of elements, in which each element has at least two different values of intensity. A comparison is made of gray tone of the image at a specific point. Threshold values are determined for two different matrices describing the intensity. The hardware used consists of two comparators (10,20) receiving the digitised half tone data. Threshold values are provided from memories (12,22) coupled to an addressing unit (14). The comparators generate outputs to control the darkness of a specific point by varying the size. ADVANTAGE - Improved resolution of gray tone print images.