Data transition enhancement

摘要

A data enhancement circuit for a facsimile receiver is provided. The circuit includes positive and negative slope detectors as well as a signal threshold detector. Incoming signals above the signal threshold and having a positive slope are considered black. Incoming signals above the signal threshold but with a negative slope are considered white. Incoming signals below the threshold are always considered white. Incoming signals above the signal threshold and with a negative slope having a slope magnitude less than a predetermined slope magnitude are considered gray. The circuit of the present invention reacts to high speed data and provides enhancement for images in a gray scale.