Retina based biometric authentication using phase congruency

In the evolving paradigm of biometric security concepts, retinal fundus image based authentication systems is regarded as one of the most precise and secure procedures. Although previously only high security buildings could afford to utilize this technology to control access, presently due to easier availability and affordability of high-tech equipment, building and establishments with lesser security significance are also employing and relishing the benefits of this technology. This paper presents a novel biometric authentication method using retinal fundus image which uses an extremely fast optical disc detection procedure, a new and fast vessel segmentation method based on Phase congruency and some proposed new features. Most relevant literatures reveal sole usage of green channel from RGB image. To investigate suitability of other color spaces, images of luminance (Y) and green (G) channel of RGB and YCbCr color space respectively are experimented with. Phase congruency is used for vessel segmentation which uses Fourier components to detect edges and by applying pair threshold values binary image of retinal blood vessel tree is acquired. Three different features are extracted for classification purpose. Two separate experiments are performed, EXP-1 using 18 images from 6 individuals and EXP-2 using 18 (authorized) plus 547 (intruder) images, each from a separate individual. For similarity matching, 2-D Correlation Coefficient measure is used. In EXP-1 and EXP-2, maximum accuracy of 94.44 and 93.4 % were achieved in 12.81 and 12.92 s respectively with YCbCr images.