1 / 23

Recover the tampered image based on VQ indexing

Recover the tampered image based on VQ indexing . Source: Signal Processing, Volume 90, Issue 1, Jan. 2010, pp. 331-343 Authors: Chun-Wei Yang and Jau-Ji Shen Reporter: Te-Yu Chen( 陳德祐 ). Outline. Introduction The Proposed Scheme VQ Index Embedding and Watermark Embedding

jafari
Télécharger la présentation

Recover the tampered image based on VQ indexing

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Recover the tampered image based on VQ indexing Source: Signal Processing, Volume 90, Issue 1, Jan. 2010, pp. 331-343 Authors: Chun-Wei Yang and Jau-JiShen Reporter: Te-Yu Chen(陳德祐)

  2. Outline • Introduction • The Proposed Scheme • VQ Index Embedding and Watermark Embedding • Wong et al.’s Watermarking Schemes for Authentication and Ownership Verification • Watermark Extraction and Image recovery • Experimental Results • Conclusions&Comments

  3. Public channel Embedding Received image Watermarking Data Tamper recovery OK Original image Recovered image Watermarked image Image Authentication with Tamper Detection and Recovery No Authenticate? Yes

  4. Requirements • Ability of tamper detection • Ability of tamper recovery • Image quality • Resistant to known attacks • Tamper watermarked image without being detected • Counterfeit attack • Collage attack • VQ attack • Blind attack • Cropping • Trace out the mapping correlation of blocks • The four-scanning attack(brute-force/dictionary attack)

  5. Literature • A Hierarchical Digital Watermarking Method for Image Tamper Detection and Recovery • Phen-Lan Lin, Chung-Kai Hsieh, and Po-Whei Huang, Pattern Recognition, Vol. 38, Issue 11, 2005 • A Majority-voting Based Watermarking Scheme for Color Image Tamper Detection and Recovery • Ming-Shi Wang and Wei-Che Chen, Computer Standards & Interfaces, 29, pp.561- 570, 2007 • Dual Watermark for Tamper Detection and Recovery • Tien-You Lee and Shinfeng D. Lin, Pattern Recognition, 41(11), pp.3497-3506, 2008 • Four-scanning attack on hierarchical digital watermarking method for image tamper detection and recovery • Chin-Chen Chang,Yi-Hsuan Fan, and Wei-Liang Tai, Pattern Recognition, Vol. 41, Issue 2, Feb. 2008, pp. 654-661 • Watermarking for tamper detection and recovery • Youngran Park, Hyunho Kang, Kazuhiko Yamahuchi, and Kingo Kobayashi, IEICE Electronics Express, 5(17), pp. 689-696, 2008 • Recover the tampered image based on VQ indexing • Chun-Wei Yang and Jau-JiShen, Signal Processing, 90(1), 2010, pp. 331-343

  6. Comparisons

  7. 1 1 2 2 3 3 n n Watermarking

  8. The Proposed Scheme~ Embedding Recovery Information Verification Information

  9. Recovery information ~VQ Encoding (120,155,…,80) 0 1 2 3 4 5 6 ‧ ‧ ‧ 168 ‧ ‧ ‧ 255 (90,135,…,120) (100,125,…,150) … (150,135,…,128) … (49,117,…,25) (50,42,…,98) (20,65,…,110) Original Image Index Table Codebook

  10. 10 10

  11. Verification information ~ Wong’s watermarking scheme(Embedding)

  12. Wong’s watermarking scheme~ Embedding Watermarked block Image block Original Image Watermarked Image Mo: the imagewidth (256) No: the imageheight(256) Io: the image ID(1015) r: the block index(1) the r-thimage block after setting LSB1 to 0(130, 50, 120, 80) NCHUNCHU NCHUNCHU NCHUNCHU NCHUNCHU Hr = H(256, 256, 1016, 1, 130, 50, 120, 80) = 11010110… Fr = Hr ⊕ Br = 1101 ⊕ 0100 = 1001 Pr = Ek’(Fr) = Ek’(1001) = 0011

  13. The Proposed Scheme~ Tamper detection and recovery Recovery Detection

  14. Wong’s watermarking scheme~ Detection

  15. 10 10

  16. Recovery information ~VQ Recovery (120,155,…,80) 0 1 2 3 4 5 6 ‧ ‧ ‧ 168 ‧ ‧ ‧ 255 (90,135,…,120) (100,125,…,150) … (150,135,…,128) … (49,117,…,25) (50,42,…,98) (20,65,…,110) Recovered Image Codebook

  17. Experimental Results Tampered (56% cropped) Original Lee and Lin’s scheme PSNR=26.75dB CB size: 256×4×4×256 bits The proposed scheme PSNR=29.33dB Imagesize: 256×256 pixels CB size: 256 code words Code word:4×4 pixels ITcanbeembedded into O four times

  18. Tampered Recovered PSNR=31.70dB 31.72dB 30.91dB 31.69dB Tampered Recovered PSNR=31.28dB 31.99dB 30.33dB 31.72dB

  19. Tamped Image Tamper detected images The recovered images 35.24 dB 36.53 dB 31.11 dB

  20. 49% 61% 65% 70% 29.83dB 29.16dB 28.62dB 27.66dB 75% 80% 85% 90% 26.30dB 24.41dB 22.59dB 20.12dB

  21. Conclusions An image tamper detection and recovery scheme integrating Wong’s watermarking scheme and VQ is proposed. The number of times of embedding the recovery info. into the image is adjustable. The quality of the recovered image is high. Resistant against the known attacks. (Wong et al.’s scheme is adopted)

  22. Comments Owing to the use of a public key cryptographic system, the block size should be large enough for the security concern(1024bits). However, the larger the block size is, the less precision of error detection will be. Owing to the use of a public key cryptographic system, the computational cost is high. Additional cost: code book(4×4 ×256×256 bits)

More Related