Additive spread-spectrum watermark detection in demosaicked images

Abstract

In this paper we investigate watermarking of digital camera raw images and blind detection of spread-spectrum watermarks in demosaicked images. We propose straightforward watermark embedding in sensor data combined with a novel detector. To this end, we extend a detection approach which adaptively combines the components of the demosaicked image to take advantage of the interpolated and correlated image structure within and between color channels. Experimental results confirm the benefits of the novel detection approach. Further, we experimentally assess the impact of several demosaicking methods on the detection performance.