Extended Visual Secret Sharing Schemes with High-Quality Shadow Images Using Gray Sub Pixels
نویسندگان
چکیده
An extended visual secret sharing (EVSS) scheme with innocent looking (unsuspicious) cover images was firstly proposed by Naor and Shamir. Most recent papers about EVSS schemes are dedicated to get a higher contrast of the concealed secret or a less size of shadow image. The conventional EVSS scheme uses the whiteness of black and white sub pixels to represent the gray level of the covered image while we use the gray sub pixels instead to achieve the high-quality shadow image. The term “high-quality” means that the shadow has high-quality image such as a photo picture.
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