Method to measure cups when engraving printing form of electronic engraving machine, involves taking video image of engraved cup, smoothing image and measuring cup contour

摘要

The method involves engraving a cup (36) in a printing form with an engraving organ. The cup measurements represent actual tone values. A video image is obtained of at least one cup. The cup geometry is measured by measuring the cup contour (38',38''). To reduce errors, the cup contour in the video image is smoothed, by filtering or by applying at least one mathematical smoothing function, and the measurements are taken of the smoothed contour.