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MUST Corp.

MUST Corp.

www.must.or.kr

 Microsoft CERTIFIED Partner Software Development, Web Development, Data Platform

 Microsoft Small Business Specialist

MCSD

Microsoft Certified IT Professional

Microsoft Certified Professional Developer

Watermarking

RSS
Modified on 2010/12/20 13:31 by Administrator Categorized as Digital Image Processing

protect the rights of their owners

  • Copyright identification
  • User identification or fingerprinting
  • Authenticity determination
  • Automated monitoring
  • Copy protection

조건

  • 추가된 워터마크는 눈에 보이지 않아야 함
  • 어떤 경우에서던지 제거할수 없이 강력하여야 함
  • 저작자의 정보를 내장
  • 내장된 디지털워터마크는 복잡해야 한다.

visible watermark

Image

Image

Invisible Watermark

깨지기 쉬운 워터마크

Image

강력한 워터 마크

  • compression, filtering cropping, rotation, resampling, additional watermark or noise
  • A typical image watermarking system

Image

DCT-based watermarking

Mark insertion

Setp1 : 2-D DCT of the image

Setp2 : Locate its K largest coefficients,Image, by magnitude

Setp3 : Create a watermark by generating a K-element pseudo-random sequence of numbers,Image, taken from a Gaussian distribution.

Setp4

: Image

Setp5 : Inverse DCT of the result from step 4

Mark extraction

Setp1 : 2-D DCT of the image

Setp2 : Extract the K DCT coefficients Image

Image

otherwise : unmarked or different watermark

Setp3 : Image

Setp4

: Measure the similarity

Image

Setp5

Image

MUST Creative Engineering Laboratory

ImageImage Image Image

Image Image Image Image Image Image Image

Copyright © 2010 MUST Corp. All rights reserved. must@must.or.kr
This Program is released under the GNU General Public License v2. View the GNU General Public License v2 or visit the GNU website.