A Method of Guaranteeing Image-Quality for Quantization-Based Watermarking Using a Nonorthogonal Transformation

This paper proposes a quantization-based image-quality guaranteed watermarking (IQGW) method using a nonorthogonal discrete wavelet transformation. An IQGW method generates watermarked images of a desired image quality for any image, neither with trial and error nor with image-dependent parameters. To guarantee the image-quality, the proposed method adjusts the energy of the watermark sequence to be embedded based on the relationship between a nonorthogonally transformed domain and the spatial domain for the signal energy. This proposed method extracts the embedded watermark by quantization of watermarked coefficients, no reference image, thus, is required. In addition, it is capable of controlling the objective and subjective image-quality of a watermarked image independently. With features mentioned above, the proposed method is suitable for real-time embedding of Motion JPEG 2000 videos. Moreover, it is able to fuse quantizationand correlation-based watermarking. key words: data hiding, information embedding, image-quality, quality guaranteed, watermarking