The scheme of the experiment is shown in Fig. 1. Transparent conductive layer 3 is evaporated onto the bottom surface of the glass plate 2. A train of duration 0.1 s of triangular 10 mks electrical impulses of amplitude 3 kV, steep rate 106 V/s and repetition frequency 103 Hz is applied to this grid. This generates electromagnetic field around the subject 1 positioned on the glass surface. Under the influence of the field the subject produces a burst of electron-ion emission and optical radiation light quanta in the visual and ultraviolet range. These particles and photons initiate electron-ion avalanches, giving rise to a sliding gas discharge 5 along dielectric surface. The spatial distribution of discharge channels is recorded through the glass plate by the optical system 7 with charge coupled device TV camera, analog-digital processor and digitized in the computer 8. In short, this technique is called the BIO GDV technique and images after processing are called BIO grams.

The common image processing application packages cannot be used for processing BIO-grams, because the tasks are specific. Diagnostic hypotheses must be taken into account, and processing should be done on the level of decision-making systems. Therefore, a software environment was developed for processing and analyzing BIO-grams, oriented towards the work in different problem domains. Adaptation for particular assessment is performed through a combination of optimal operations from the library for the given problem domain, selection of corresponding procedures, and (or) selection of optimal threshold values.

imgFig. a typical gas discharge image around human finger. This image is a set of pixels with a certain luminosity assigned to every pixel. The central oval shape of the image represents fingerprint, typically luminosity monotonically decreases along any radial direction.

imgFig.1 The scheme of the experiment. 1 - - biological object under study; 2 – glass electrode; 3 – conductive transparent layer; 4 - generator of electric pulses; 5 – gas discharge; 6 – light radiation; 7 – optical system and CCD TV camera; 8 – computer.

The following main algorithms are included in the library [3,6]:

  • Luminescence Area. Amount of light quanta generated by the subject in computer units - pixels (the number of pixels in the image having brightness above the threshold).
  • Normalized Luminescence area. The ratio of image area to the area of the inner oval (representing fingerprint). Internal noise. Amount of light in the inner oval (fingerprint).
  • Isoline radius. Average radius measured from the center of an image to the external contour (isoline).
  • Intensity. Relative brightness of image pixels measured in computer units from 0 to 255.
  • Inner circle radius. Radius of the circle inscribed in the inner oval (fingerprint).
  • Isoline length. The length of the external contour of an image.
  • Isoline fractality. Fractal dimension of the external contour represented as quasi-infinite line.
  • Isoline Entropy. The ratio of an image’s external contour to its internal contour.
  • Form Coefficient. Calculated according to the formula: FC = Q = k*L2/S, where L is the length of an image’s external contour and S is the image area.