Invisible calibration pattern based on human visual perception

In this paper, we propose an arrangement and detection method of an invisible calibration pattern based on characteristics of human visual perception. A calibration pattern is arranged around contents where invisible data is embedded, as some feature points between an original image and the scanned image for normalization of the scanned image. However, it is clear that conventional methods interfere with page layout and artwork of contents. Moreover, conventional visible patterns show a third person the position of embedded data. Therefore, visible calibration patterns are not suitable for security service. The most important part of human visual perception in the proposed method is the spectral luminous efficiency characteristic and the chromatic spatial frequency characteristic. In addition, a back ground color in surrounding of contents is not restricted to uniform color by using the proposed calibration pattern. It is suggest that the proposed method protect page layout and artwork.