Wavelet-based Contrast Computation and Application to Digital Image Watermarking
نویسندگان
چکیده
We introduce an isotropic measure of local contrast for natural images that is based on analytic filters and present the design of directional wavelet frames suitable for its computation. We show how this contrast measure can be used within a masking model to facilitate the insertion of a watermark in an image while minimizing visual distortion.
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