HW10 - watermark should be detectable even after the watermarked image is modified somewhat(saved with a different compression ratio printed copied

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EE4414 Multimedia Communication System II, Fall 2005, Yao Wang Homework 10 (Data Hiding, Watermarking, Steganography) ___________________________________________________________________________________ Review questions 1. Describe the differences between data hiding, watermarking, and steganography. What are their respective applications and requirements? Is one a special case of another? 2. The following are some possible applications of watermarking. Describe what they are and their requirements. a. Ownership assertion b. Fingerprinting c. Copy prevention and control d. Detection of unauthorized alteration (authenticate integrity of the data) 3. What is the difference between robust and fragile watermarks? Which technique you will use for the above applications (a-e in Prob. 2)? 4. Propose one possible technique, for embedding a watermark (invisible) in an image for ownership assertion. Also describe the corresponding watermark detection scheme. Remember that the watermarked image should look almost identical to the original image, and that the
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Unformatted text preview: watermark should be detectable even after the watermarked image is modified somewhat (saved with a different compression ratio; printed, copied and then scanned; etc.) 5. What is steganography? What are the design objectives for a steganography system? 6. Propose one possible technique, to embed a secret message in an image or a song or a video, and a corresponding algorithm for deciphering the message. Remember that the image (or song or video) after embedding (the stegoed media) should look indistinguishable from the original one, and the intended recipient of the stegoed media should be able to decipher the secret message (with the knowledge of a secret key and stego algorithm) exactly, and that it should be difficult for a steganalysis system (the Warden Wendy) to detect the presence of the secret message. 7. What is steganalysis? What are the design objectives for a steganalysis system? What are the two types of staganalysis techniques?...
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This note was uploaded on 01/22/2012 for the course EE 4414 taught by Professor Wang during the Fall '07 term at NYU Poly.

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