NCJ Number
140923
Journal
Journal of Forensic Sciences Volume: 38 Issue: 1 Dated: (January 1993) Pages: 143-146
Date Published
1993
Length
4 pages
Annotation
An IBM-compatible personal computer, a hand scanner, and commonly available software were used in a recent criminal case involving the restoration of an obliterated message.
Abstract
The laboratory received a 1-page letter written in pencil by a jail inmate who had subsequently erased his message. Attempts at restoration by traditional photographic methods, including infrared, ultraviolet, and oblique lighting, were only partially successful. It was then suggested that computer image enhancement techniques be employed. The document was scanned and digitized, and the text was restored to readability by performing such image manipulations as gray-scale equalization and contrast enhancement. Finished images were viewed on a monitor screen and then sent to a print shop for high resolution output. Results showed that a rudimentary image enhancement program can easily be set up in many laboratories and offices using inexpensive hardware. 3 references and 3 figures