Proceedings Article | 22 March 2013
Proc. SPIE. 8665, Media Watermarking, Security, and Forensics 2013
KEYWORDS: Visualization, Calibration, Image segmentation, Scanners, Digital watermarking, Computer programming, Printing, Halftones, Performance modeling
Embedding data in hard copy is in widespread use for applications that include pointing the reader to on-line
content by means of a URL, tracing the source of a document, labeling, and packaging. Most solutions involve
placing overt marks on the page. The most common are 1D, 2D, and 3D (color) barcodes. However, while
barcodes are a popular means for encoding information for printed matter, they add unsightly overt content.
In order to avoid such overt content, Stegatones are clustered-dot halftones that encode a data payload by
single-pixel shifts of selected dot-clusters. In a Stegatone, we can embed information in images or graphics –
not in the image file, as is done in traditional watermarking, but in the halftone on the printed page. However,
the recovery performance of stegatones is not well understood across a wide variety of printing technologies,
models, and resolutions, along with variations of scanning resolution. It would thus be very useful to have a
tool to quantify stegatone performance under these variables. The results would then be used to better calibrate
the encoding system. We develop and conduct a test procedure to characterize Stegatone performance. The
experimental results characterize Stegatone performance for a number of printers, scanners, and resolutions.
