Image quality defect detection via sensor characterization and halftone dot classification

摘要

What is disclosed is a system and method for image quality (IQ) defect detection via classification of halftone dots present on customer prints. In one embodiment, spatially-varying thresholds are applied on the sensed image in order to classify the halftone dots for IQ defect detection. The resolving power of the sensor is characterized and the sensor responses to patches printed with the print device are characterized. A de-blurring filter is designed which is appropriate for compensating the characterized resolving power of the sensor. Image enhancement is applied to the image using the de-blurring filter. Halftone dots present on the prints are classified by analyzing the enhanced image with the results of the sensor response characterization. Once classified, single separation halftone dot images can be more readily analyzed for defects. The present method allows sensor resolution as low as the size of the halftone dots of the printer under test.