Dark current elimination in security imaging systems

This paper deals with advanced method for elimination of the dark current in security images acquired by simple camera with charged coupled device (CCD) sensor. There will be discussed the correction method based on the modeling of the useful security image data and dark current in the wavelet domain. As the model for the dark frame (mapped dark current) image and for the light image the generalized Laplacian was chosen. The models parameters were estimated using moment method, whereas an extensive measurement on camera were proposed and done. This measurement simplifies estimation of the dark frame model parameters. Finally a set of the security image data were corrected and then the objective criteria for an image quality evaluation were applied.