1 / 14

Writer Identification

Writer Identification. Lewis Griffin & Andrew Newell Computer Science, CoMPLEX University College London. L.Griffin@cs.ucl.ac.uk. Example 1: same language, different text. B. A. B. C. Example 0: same language, same text. Example 1: same language, different text.

saddam
Télécharger la présentation

Writer Identification

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. Writer Identification Lewis Griffin & Andrew NewellComputer Science, CoMPLEXUniversity College London L.Griffin@cs.ucl.ac.uk

  2. Example 1: same language, different text B A B C

  3. Example 0: same language, same text Example 1: same language, different text Example 2: different language, different text C A B C

  4. Macro Features Micro Features http://www.moralesforensics.com/identification.htm

  5. Definitive, highly-cited publication. • Basis of the CedarFox document analysis software package. • Analyzed the uniqueness of the macro and micro features used by experts.

  6. Task: pick out the sample by the same writer from a set of 200 writers(same language, same text). Srihari et al. (CedarFox?) Using expert-style macro features, 40% correct. Using expert-style micro features, 86% correct. With macro & micro features,91% correct. Newell & Griffin Using our macro features,95% correct (on same language, different text).

  7. Our Primary Research Area… Basic Image Features (BIFs)A computational modelof Human Vision +2 +1 +2 +1 +1 +1

  8. …looked sufficiently promising when used to characterize the texture of sand grain images, that… Sand grain appearance under electron microscopy reveals distinctive, geographically specific textures Basic Image Features make the texture differences obvious to a computer

  9. …the Atomic Weapons Establishment funded a project to investigate the forensic potential of our texture analysis method for particulate identification Electron Microscopy of Sand Grains weathered at different wind speeds Newell, A. J., Morgan, R. M., Griffin, L. D., Bull, P. A., Marshall, J. R., & Graham, G. (2012). Automated Texture Recognition of Quartz Sand Grains for Forensic Applications.Journal of Forensic Sciences.

  10. Then, by chance, we came across the problem ofwriter identification…

  11. Not knowing the importance experts attach to comparing individual letters we tried our texture approach…

  12. We got a perfect score, crashed the website, and won the competition.

  13. And retained our title last year in a harder competition with more entrants.

  14. Summary • Computers can be more accurate than experts… • …by using methods that do not mimic those experts. • The Newell-Griffin method is currently world-leading. • It is based on a method of texture analysis. • That also works for quartz grains, biomedical image analysis,general-purpose object recognition,… • That derives from a model of how human vision works. • We are keen to take advice on this handwriting work… • …and to find other forensic applications of our image analysis/recognition expertise.

More Related