Evaluation of halftone techniques using psychovisual testing and quantitative quality measures

The quality of an image can be evaluated by performing a psychovisual test or by using quantitative quality measures. In order to assess the performance of different halftone techniques, gray scale images are halftoned in various ways and then presented to human viewers for quality evaluation. Quantitative quality criteria, such as edge correlation, mean square error and local error measures are also used for quality evaluation of the halftone images. Since the ultimate judges of image quality are human viewers, the success of these quantitative criteria as quality measures for halftones is assessed by comparing their results with the results of the psychovisual test.