MASTER THESIS Video Watermarking - Computer Graphics Group ...
MASTER THESIS Video Watermarking - Computer Graphics Group ...
MASTER THESIS Video Watermarking - Computer Graphics Group ...
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5.4.7 Sharpening<br />
Sharpening is a kind of high-pass filter mentioned in Section 4.3.1, thus<br />
high probabilities are expected in case of noise method. The test uses MPlayer<br />
“unsharp” filter with opposite coefficient than in the blurring test. Again, three<br />
convolution sharpening masks are applied (see column in Table 10 named SM).<br />
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Table 10: Sharpening test results<br />
The sharpening filter works pretty well not only when using noise method<br />
but also when using both block and coefficient methods. The test results show<br />
that it does not matter which size of the convolution mask is used.<br />
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