Method for locating the transitions between the elements of a bar code

摘要

For reading bar and stacked codes, it is proposed to determine the transitions between the code elements as the crossing points between a sampled video signal, representative of the intensity of light diffused by a code along a scan line thereof, and a low-pass filtered version thereof, or between two low-pass filtered versions thereof. The method is suitable to be implemented through analog or digital hardware, and via software. <IMAGE>