Welcome Guest, you are in: Login

MUST Creative Engineering Laboratory

RSS RSS

Navigation



Technical Doc



Search the wiki
»

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

Page History: Watermarking

Compare Page Revisions



« Older Revision - Back to Page History - Newer Revision »


Page Revision: 2010/12/20 13:26


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

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.