Watermark Recovery from a Dual Layer Hologram with a Digital Camera

Abstract

Abstract. In this paper we present a method for reading a watermark from a dual layer hologram image with a digital camera. Here the base of the hologram out of which the hologram was designed is a binary image. The hologram obtained is placed on a planar surface and an image is captured from the hologram by setting up a light source and a digital camera on appropriate distances and angles relative to the hologram. The captured image is corrected from affine distortions and a saliency detector based segmentation is performed for the image. The watermark is read from the resulting reconstructed binary image. The obtained results show that the watermark can be recovered perfectly from a dual layer hologram with a proper setting of the camera and light sources.

Cam-Unet: Print-Cam Image Correction for Zero-Bit Fourier Image Watermarking

“…However, several challenges arise in this scenario, primarily stemming from perspective transformations and alignment issues when capturing images from different viewpoint angles. These challenges can affect the accuracy of watermark detection [5], as changes in perspective can distort the original watermark pattern, making it difficult to detect accurately. Figure 1 shows the print-cam watermarking process.…”