Types Of Minutiae Research Articles

Cancelable fingerprint templates using minutiae-based bit-strings

It has become critical to protect biometric templates in the current biometric community. One way for doing this is using a cancelable biometric method, which transforms original biometric templates in a non-invertible way and uses those transformed templates to verify a person's identity. In this paper, we propose a new method to generate cancelable bit-strings (templates) from fingerprint minutiae. Our method is to provide a simple mean to generate cancelable templates without requiring for pre-alignment of fingerprints. The main idea is to map the minutiae into a predefined 3 dimensional array which consist of small cells and find out which cells include minutiae. To do this, we choose one of minutiae as a reference minutia and other minutiae are translated and rotated in order to map the minutiae into the cells based on the position and orientation of the reference minutia. After mapping, we set the cells in the 3D array to 1 if they include more than one minutia otherwise the cells are set to 0. A 1D bit-string is generated by sequentially visiting the cells in the 3D array. The order of the 1D bit-string is permuted according to the type of reference minutiae and user's PIN so that we can regenerate new templates when we need them. Finally, cancelable bit-strings are generated by changing the reference minutia into another minutia in turn. In the experiments, we evaluate our method using the FVC2004 database and show that the performance is better than that of a previous method.

Computation of Likelihood Ratios in Fingerprint Identification for Configurations of Any Number of Minutiæ

Recent court challenges have highlighted the need for statistical research on fingerprint identification. This paper proposes a model for computing likelihood ratios (LRs) to assess the evidential value of comparisons with any number of minutiae. The model considers minutiae type, direction and relative spatial relationships. It expands on previous work on three minutiae by adopting a spatial modeling using radial triangulation and a probabilistic distortion model for assessing the numerator of the LR. The model has been tested on a sample of 686 ulnar loops and 204 arches. Features vectors used for statistical analysis have been obtained following a preprocessing step based on Gabor filtering and image processing to extract minutiae data. The metric used to assess similarity between two feature vectors is based on an Euclidean distance measure. Tippett plots and rates of misleading evidence have been used as performance indicators of the model. The model has shown encouraging behavior with low rates of misleading evidence and a LR power of the model increasing significantly with the number of minutiae. The LRs that it provides are highly indicative of identity of source on a significant proportion of cases, even when considering configurations with few minutiae. In contrast with previous research, the model, in addition to minutia type and direction, incorporates spatial relationships of minutiae without introducing probabilistic independence assumptions. The model also accounts for finger distortion.

Preprocessing and postprocessing for skeleton-based fingerprint minutiae extraction

In this paper, we propose to use the fingerprint valley instead of ridge for the binarization-thinning process to extract fingerprint minutiae. We first use several preprocessing steps on the binary image in order to eliminate the spurious lakes and dots, and to reduce the spurious islands, bridges, and spurs in the skeleton image. By removing all the bug pixels introduced at the thinning stage, our algorithm can detect a maximum number of minutiae from the fingerprint skeleton using the Rutovitz Crossing Number. This allows the true minutiae preserved and false minutiae removed in later postprocessing stages. Finally, using the intrinsic duality property of fingerprint image we develop several postprocessing techniques to efficiently remove spurious minutiae. Especially, we define an H-point structure to remove several types of spurious minutiae including bridge, triangle, ladder, and wrinkle all together. Experimental results clearly demonstrate the effectiveness of the new algorithms.

Genetics of epidermal ridge minutiae

Epidermal ridge minutiae have been utilized widely in Forensic Sciences for personal identification for a long time; but genetical significance of minutiae is yet to be understood thoroughly. In the present communication an attempt has been made to study the genetical aspects of finger ridge minutiae on the basis of family material. Data for the present study were collected from 76 families belonging to the Namasudras, a Scheduled Caste residing in Nadia district, West Bengal, India. An eight-fold classification of minutiae was followed in the present study. Out of eight minutiae types ridge end and connecting ridge have shown the maximum and minimum occurrences, respectively. Bilateral difference in minutia types was not evident but the sex difference was found to be significant. The genetics of minutia types was studied by familial correlation (r) and heritability (h 2) estimates. Statistically significant familial correlation values and high heritability estimates for some of the minutia types such as fork, ridge end and total minutiae are suggestive of hereditary control of minutiae. The results of the present study suggest that minutiae showing significant correlation values and high heritability estimates (more than 60%) are useful in genetical studies and perhaps diagnosis of some genetical disorders in addition to their regular application in personal identification.

A Systematic Study of Epidermal Ridge Minutiae

Abstract To permit the testing of a number of basic hypotheses regarding the relationship between neighboring minutiae, epidermal ridge minutiae on the distal portions of 412 thumbprints have been surveyed. For each thumbprint a centrally located focal minutia was chosen; neighboring minutiae were then sampled. Minutiae were considered to be neighbors if there were no other minutiae in a rectangular region defined by the two minutiae and the ridge system. For each minutia the following data were recorded: minutia type, orientation, ridge count from the focal minutia, and the intervening distance along the ridge flow. The number of neighbor minutiae was found to be normally distributed. Minutia orientation frequencies on the right and left hands were found to be unequal and to show a mirror image relationship. The incidence of particular minutia orientations and types were found to vary with ridge count from the focal minutia. Linear descriptions of these relationships were found to be adequate after adjustments were made for geometrical restrictions present for ridge counts of one, zero, and negative one. Predicted frequencies of minutia types and orientations for each ridge count were found to be in acceptable agreement with the observed frequencies.

A Method for the Description of Minutia Pairs in Epidermal Ridge Patterns

Abstract A descriptive method is presented that allows documentation of minutia configurations in epidermal ridge patterns. The method incorporates the basic features relevant to fingerprint comparison: minutia types, orientations, and relative positions. Provision is also made for the ambiguities in minutia type which are an inevitable feature of any fingerprint comparison process. A descriptive method incorporating these features is needed to study systematically the variation of epidermal ridge minutiae and to test the existing hypotheses regarding the frequencies of occurrence of specific minutia configurations.

Fingerprint Comparison. II: On the Development of a Single Fingerprint Filing and Searching System

A FORTRAN program has been written to compare the minutiae coded in an"unknown" fingerprint with the minutiae of fingerprints stored in a data base. The criteria for matching are scores based on the type and number of minutiae matched. Minutiae of low relative frequency have higher scoring weights than those that are more common. The matching mechanism is tested by using a fingerprint coded several times, first by a single individual and then by six other individuals who have no previous knowledge about fingerprints. These tests yield satisfactory results.