In this paper a system and method of automated analysis of electrophoresis
gels by image digitalization and processing are reported. The image digital
ization system is formed by a non-intensified colour charge-coupled device
camera interfaced to a microcomputer through a frame grabber that allows im
age acquisition to be performed in real time. The illumination and image ac
quisition conditions will be discussed. A few different macro routines for
image processing and data analysis were built. They were designed to cope s
pecifically with the different requirements of the analysis of the differen
t types of electrophoresis gel employed. After selection of the appropriate
routine the automated evaluation process begins with digitalization and pr
ocessing of the images in order to enhance the contrast of the images and t
o detect relevant features. The image-processing techniques employed includ
e histogram equalization and contrast enhancement, noise reduction by low-p
ass Fourier filtering, edge enhancement and location by the application of
differential operators, posterization or binarization, and blob analysis, m
atching and feature extraction. The obtained images are also compressed and
stored on the patient's files for future reference.