08601538 is referenced by 8 patents and cites 10 patents.

An automated test to tell computers and humans apart is disclosed, comprising displaying on a computer screen an animation comprising of a foreground and a background, one of the foreground comprising a plurality of typographical characters and the other comprising partial obstruction of the typographical characters, and wherein the animation comprises relative motion between the background and foreground. The automated test may comprise displaying on a computer screen an image, and requiring the user to perform operation on the image to resolve an encoded solution. The test may also comprise displaying on a computer screen a video clip, and requiring a user to provide an input corresponding to subject matter presented in the video clip.

Title
Motion and interaction based CAPTCHA
Application Number
11/508423
Publication Number
8601538 (B2)
Application Date
August 22, 2006
Publication Date
December 3, 2013
Inventor
David M Hilbert
Palo Alto
CA, US
Eleanor G Rieffel
Mountain View
CA, US
Pernilla Qvarfordt
Los Altos
CA, US
Agent
Sughrue Mion PLLC
Assignee
Fuji Xerox
JP
IPC
H04L 29/06
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