Hannu Saarelma

Development of a balanced test image for visual print quality evaluation

A test image for color still image processes was developed. The image is based on general requirements on the content and specific requirements arising from the quality attributes of interest. The quality attributes addressed in the study include sharpness, noise, contrast, colorfulness and gloss. These were chosen based on visual relevance in studies of the influence of paper in digital printing. Further requirements such as arising from the use cases of the image are discussed based on eye tracking data and self-report of the usefulness of different objects for quality evaluation. From the standpoint of being sufficiently sensitive to quality variations of the imaging systems to be measured the reference test image needs to represent quality maxima in terms of the relevant quality parameters. As for different viewing times, no object should be exceedingly salient. The paper presents the procedure of developing the test image and discusses its merits and shortcomings from the standpoint of future development.

Image rendering in low-end color printing

The development of networked, distributed, digital color printing gives rise to new requirements of managing color. In the paper, platform for automatic, source and device independent color correction is defined and its implementation outlined. Moreover, a model for capacity in distributed digital printing is presented.