Invisible Print-Type Calibration Pattern Based on Human Visual Perception

In the print-type steganographic system and watermark, a calibration pattern is arranged around contents where invisible data is embedded, as plural feature points between an original image and the scanned image for normalization of the scanned image. In this paper, we propose an arrangement and detection method of an invisible calibration pattern based on the characteristics of human visual perception. The most important part of human visual perception in the proposed method is the spectral luminous efficiency characteristic and the chromatic spatial frequency characteristic. We embed the calibration pattern in an original image by adding high frequency component to blue intensity in a limited region. It is suggest that the proposed method protect page layout and artwork of original contents. In order for the detection of embedded calibration pattern to achieve high-speed and accurate processing the detection method composed from brief weak classifiers will be proposed.