Algorithm In Iris Recognition Systems And Driver Design

Iris recognition is an emerging biometrics technology. Compared with the other biometrics technologies (fingerprint recognition, facial recognition voice recognition, etc.), iris recognition has the following characteristics: stability, high reliability, non-contact. Therefore, it will be widely used in the future.This thesis made research and improvement of the iris recognition algorithm. The main tasks of this thesis include:First, at the iris image preprocessing stage, a new localization method is proposed. To localize the interior edge, the thesis first converts the iris image into bi-value image. Then, with boundary tracing technology, the interior edge of the iris will be found. Finally, the precise interior edge will be localized with circle fitting. At the image enhancing stage, we use CLAHE to overcome the non-uniform illumination problem.Second, at the feature extraction stage, we propose a novel multi-resolution approach based on wavelet packets transform (WPT) for iris texture analysis and recognition. The development of this approach is motivated by the observation that dominant frequencies of iris texture are located in the low and middle frequency channels. With an adaptive threshold, we quantize WPT subimages coefficients into 1, 0 or -1 as iris signature. This signature presents the local information of different irises. Manhattan Distance is used to measure the degree of dissimilarity between two iris sets.Third, introduce the embedded iris recognition system based on DSP. Design the USB driver for the embedded system, which including firmware, the WDM dirver, and the Win32 application program. The USB interface connects PC and our embedded system.The identification experiments are done in the CASIA iris database (version 2.0), and good recognition results are achieved.