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Computer Enhancement

Occasionally, conventional techniques fall short of providing images on which significant conclusions may be based. In many of these cases, sophisticated computer enhancement techniques can extend the forensic reach of the examiner and reveal crucial detail that the photographic process and analog techniques fail to deliver. These may be achieved through the following:

: Noise Reduction
: Multi-frame Averaging (video)
: Edge Recognition
: Fast Fourier Transform
: Equalization
: Image Subtraction

Brian Dalrymple has provided investigative consultation and support in the area of computer image enhancement since 1990, and has tendered opinion evidence on his findings in court.

Here is an example:

The first image is the photograph of the currency as we see it. Notice the fingerprint on top of it. Now look at the second image; it is an image of the fingerprint alone. You can see in the background the eye of the picture on the currency.