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Subject: Guestion need Implement and answer?
Date: Thu, 25 Sep 2008 05:38:02 +0000 (UTC)
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Implement the spread-spectrum watermarking.
 Your program should embed 16 bits of &#8216;intelligence information&#8217; in an image of arbitrary size.
 The detector should be able to detect 100% of the embedded bits.
 The report should address the following questions
a. How does the spreading of message bits occur?
b. What is the difference between the blind embedding and non-blind embedding?
c. Why do you need the prefiltering step in blind detection?
d. Why do you think the whole process work?

2. For the above code, 
tweak the gain/strength parameters to come up with a graphical relation 
between perceptibility and detectability of the watermarked image.
 You may use PSNR metric for perceptability and bit error rate for the detectability.