| 摘要 |
A PDL or other type of line drawing program mathematically generates an edge between white and black regions. For curved edges, the edge is transformed into a plurality of piecewise linear edge segments (20). Pixels (u,v) in the vicinity of the edge are identified (12). Each pixel is assigned a magnitude value in accordance with its distance from the mathematically defined edge relative to a width or gray span (22) of the selected vicinity. The magnitudes in each of a plurality of subregions of the selected vicinity define a sloping plane (42). The threshold (t), such as a value mid-way between the extremes of the selected vicinity, defines a plane (44) which intersects the sloping plane. The line (46) of intersection defines the edge. A hyperacuity printer receives slope of the plane relative to a scan and orthogonal directions of the printer, and a magnitude for each pixel. Based on the slope and magnitude information, the printer determines (16) intensity and fast scan direction offset of a corresponding exposure value and prints (17) a corresponding dot.
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