05155343 is referenced by 146 patents and cites 17 patents.

A bar code reader includes an optical system for storing a two dimensional image in memory, which stored two dimensional image contains a bar code symbol. A method and apparatus is disclosed for detecting the location of said bar code image by computing the accumulated sum of the products of the derivatives of respective first and second scan lines as a location score for the image under consideration. The higher the location score, the higher the probability that the area under consideration contains a bar code image. Also, a method and apparatus is disclosed for determining the fine orientation of a located bar code image by the cross-correlation of interpolated scan line data. The bar code image is filtered by shifting interpolated scan line data in accordance with the detected peak of the cross-correlation and combining the shifted scan line data.

Title
Omnidirectional bar code reader with method and apparatus for detecting and scanning a bar code symbol
Application Number
7/501259
Publication Number
5155343
Application Date
March 28, 1990
Publication Date
October 13, 1992
Inventor
Eric P Batterman
207-11 Salem Ct., Princeton, 08540
NJ, US
Donald G Chandler
43 Springwood Ct., Princeton, 08540
NJ, US
Agent
Allan J Jacobson
IPC
G06K 9/18
G06K 7/10
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