Robust wavelet-based logo watermarking for colour images

Abstract

Colour image watermarking is usually achieved by modifying the image luminance or by processing each colour channel separately. This paper presents a watermarking approach by hiding logo duplicates in DWT domains of the achromatic component of the colour image, and then a proposed technique of saturation adjustment is used to distribute the marks into each colour channel. To improve the detection robustness, an adaptive weighting scheme is also proposed to combine the extracted watermark duplicates in the extraction stage. Experimental results demonstrate that the proposed methods successfully make the watermark perceptually invisible and robust to image processing operations such as low-pass filtering, JPEG, JPEG 2000, scaling and cropping.

Keywords:

• DIGITAL WATERMARK
• DISCRETE WAVELET TRANSFORM
• SATURATION ADJUSTMENT
• JPEG COMPRESSION
• JPEG 2000 COMPRESSION