Geographic Information Systems and Spatial Analysis – Part 1: Quantifying Fingerprint Patterns and Minutiae Distributions Ryan J. Stanley*1, Emma K. Dutton1,2, Stephen B. Taylor1, Patrick R. Aldrich1 and Bryan E. Dutton1 1Division 2Oregon of Natural Sciences and Mathematics Western Oregon University State Police, Forensic Services Division Outline • Background • Methodology • Preliminary Results • Summary Background: Impetus for the study • Feb. 2009 NAS report, “Strengthening Forensic Science in the United States: A Path Forward” – Recommendation 3: Indicated need to improve the scientific accuracy and reliability of forensic science evidence. • Sept. 2009 Awarded NIJ Grant: Fundamental Research to Improve Understanding of the Accuracy, Reliability, and Measurement Validity of Forensic Science Disciplines (emphasis on impression based evidence) Applications of GIS GIS: Cartography + Statistical Analysis + Database Technology A. Example GIS Application B. GIS Applied to Fingerprints Customers V e c t o r Core to Minutiae Distances and Ridge Counts Streets Parcels Minutiae Elevation R a s t e r Source: ESRI Land Usage Fingerprint Skeleton Real World Fingerprint Image Geographic Information Systems and Spatial Analysis • GIS is commonly deployed for crime pattern analysis and emergency management • Use as an analytical tool for fingerprint analysis is sparse to absent in the literature • GIS widely applied in the Geosciences for spatial analysis including data modeling, image processing, grid algebra, surface analysis, network analysis and visualization • GIS extensively used in Geography as a tool for performing statistical analysis and probability modeling • GIS application to fingerprint analysis, identification and pattern characterization represents an untapped resource Methodology • Fingerprint image acquisition and minutiae detection • Georeferencing and verification • GIS data conversion and management • Spatial analysis of ridge line and minutiae distributions • Statistical analysis and probability modeling 125 75 100 100 mm 0 25 50 100 mm Y Coordinate (mm) 150 Georeferencing: Standardized Coordinate System 0 25 50 75 100 X Coordinate (mm) 125 150 GIS Data Conversion Fingerprint Image 100 Fingerprint Minutiae 100 100 Vectorized Ridge Lines 100 100 100 Minutiae Attribute Table X_COORD Y_COORD MIN_DIR PT_ID MIN_TYP PRNT_TYP File_Id 100.00 100.00 180 1000 C RS 1_87_ri 96.42 95.12 -1 2001 D RS 1_87_ri 88.49 92.79 45 1 A RS 1_87_ri 88.87 92.36 225 2 B RS 1_87_ri 89.15 100.05 214 3 B RS 1_87_ri 89.61 88.81 68 4 A RS 1_87_ri 90.50 90.48 56 5 A RS 1_87_ri 90.83 89.18 236 6 B RS 1_87_ri 91.20 88.75 68 7 A RS 1_87_ri 91.35 93.97 45 8 B RS 1_87_ri 91.77 107.65 225 9 B RS 1_87_ri 92.25 100.28 202 10 A RS 1_87_ri 92.72 104.05 34 11 A RS 1_87_ri Oregon Fingerprint Database Table 1. Frequency of Pattern Type by Finger and Hand Left Loop Right Loop Double Loop Whorl Whorl Arch Tented Arch TOTAL Left Index 125 45 28 58 18 30 304 Right Index 48 110 15 78 21 36 308 Left Thumb 173 2 66 41 9 0 291 2 152 63 74 6 0 297 348 309 172 251 54 66 1200 Left Loop Right Loop Double Loop Whorl Whorl Arch Tented Arch TOTAL Left Hand 298 47 94 99 27 30 595 Right Hand 50 262 78 152 27 36 605 FINGER Right Thumb TOTAL HAND Fingerprint Skeletonization and Vectorization Core Coded to Ridgeline Delta Ridge Attributes Count RidgesRidge Ending 16 - Ridge Ending Ridge Ending - Bifurcation Distance 11.11 mm Line Ridge Ending - Ridge Ending Bifurcation - Bifurcation Ridge Ending - Hull Density ridges/mm Bifurcation 1.53 - Bifurcation Bifurcation - Hull Hull - Hull TIN (Delaunay) Triangles 2 20 2 8 5 7 1. Vectorized fingerprint 5 4 3. TIN polygons 2 11 2 4 3 4 4 1 03 1 1 2 3 4 2 0 11 1 0 2 0 1 0 001 0 3 1 1 12 0 3 3 0 2 2 20 1 3 4 1 1 9 0 2 8 8 1 5 3 2 2 2 1 3 2 4 2 4 2 3 2 5 34 9 3 4 1 2 4 2 0 1 5 0 12 1 2 0 0 0 1 1 0 01 1 6 2 1 0 22 4 2 2 1 1 2 2 1 1 4 3 0 3 4 0 1 3 1 2 0 2 1 3 4 4 3 0 1 8 0 2 2 1 1 2 2 0 0 3 3 2 2 3 0 1 2 1 7 2 0 4 13 5 11 1 5 11 13 2 7 2 1 1 1 11 2 1 4 1 1 1 1 3 0 2 3 33 0 1 1 4 0 3 3 2 1 3 8 3 2 0 5 2 4 7 4 5 43 1 7 3 6 2 9 2 0 0 1 6 0 21 1 6 2 1 0 2 7 3 2 1 6 0 53 11 2 4 3 2 3 1 0 2 1 3 0 44 2 5. TIN ridge counts 2 4 3 7 2 4. TIN polylines 8 64 7 3 4 7 6 1 4 5 7 7 1 1 1 5 4 4 7 4 0 2. Minutiae 2 3 1 2 4 0 13 3 2 PRELIMINARY RESULTS: Spatial Analysis of Minutiae Distributions Spatial Distribution of Minutiae 340 C. Whorls n = 348 A. Left Slant Loops Azimuth (deg.) Azimuth (deg.) 0 0 350 10 20 330 340 30 320 310 300 290 70 80 % Freq. 260 2% 90 3% 250 100 110 240 290 80 % Freq. 230 190 180 170 160 B. Right Slant Loops 340 0 10 340 20 320 310 260 300 290 70 280 80 % Freq. 1% 2% 90 3% 250 100 110 240 120 230 130 220 140 210 150 160 0 10 120 230 130 220 140 150 160 n = 66 Azimuth (deg.) 20 340 80 % Freq. 2% 90 3% 250 100 110 240 120 230 130 140 210 150 160 20 30 40 50 300 280 220 10 310 70 1% 0 320 290 270 350 330 60 190 180 170 190 180 170 F. Tented Arches 50 200 100 110 40 0% 90 3% 250 30 260 2% 240 n = 172 300 60 270 350 1% 210 310 50 190 180 170 0% 200 320 40 200 270 160 330 30 0% 80 % Freq. Azimuth (deg.) 330 260 190 180 170 D. Double Loop Whorls Azimuth (deg.) 350 60 150 200 n = 309 50 70 140 210 40 290 130 220 30 280 120 150 200 100 110 140 210 90 3% 240 130 220 2% 250 120 230 70 280 260 20 300 60 1% 10 310 50 0% 0 320 40 270 350 330 30 300 280 1% 340 20 310 60 0% 10 320 50 270 350 n = 54 Azimuth (deg.) 330 40 E. Arches n = 251 60 290 70 280 80 % Freq. 270 0% 260 1% 2% 90 3% 250 100 110 240 120 230 130 220 140 210 150 200 190 180 170 160 B. Right Slant Loops 120 4 -0 .4 .1 -0 .0 76 -0 0. 14 1 0. 07 6 1 03 6 1 1 110 120 n = 66 80 90 100 110 120 110 100 F. Tented Arches n = 172 110 100 0. 120 100 90 01 0 120 110 90 80 90 n = 54 100 100 80 80 90 100 110 120 90 D. Double Loop Whorls n = 309 80 0.436 80 80 120 0. 110 0.14 120 100 E. Arches 0.076 90 100 90 80 90 0.036 110 120 n = 251 110 120 110 100 90 80 80 0. 0 C. Whorls n = 348 A. Left Slant Loops .0 36 0.01 -0 -0 .0 1 0.001 01 0 36 Average Minutiae Density (Avg. Number Minutiae / Sq. mm) 0 2-mm Grid Cell Minutiae Density All Minutiae 80 90 100 110 120 80 90 100 110 120 B. Right Slant Loops 110 D. Double Loop Whorls 120 120 4 -0 .4 .1 -0 .0 76 -0 0. 14 1 0. 07 6 1 03 6 1 1 110 120 n = 66 80 90 100 110 120 100 110 100 F. Tented Arches n = 172 90 100 01 0 120 100 80 90 90 n = 54 100 90 110 120 110 100 90 80 80 80 0.436 80 80 n = 309 0. 120 0. 110 0.14 120 100 E. Arches 0.076 90 100 90 80 90 0.036 110 120 n = 251 110 120 110 100 90 80 80 0. 0 C. Whorls n = 348 A. Left Slant Loops .0 36 0.01 -0 -0 .0 1 0.001 01 0 36 Average Minutiae Density (Avg. Number Minutiae / Sq. mm) 0 2-mm Grid Cell Minutiae Density Ridge Endings 80 90 100 110 120 80 90 100 110 120 110 B. Right Slant Loops 120 D. Double Loop Whorls 120 4 -0 .4 .1 -0 .0 76 -0 0. 14 1 0. 07 6 1 03 6 1 1 110 120 n = 66 80 90 100 110 120 120 100 F. Tented Arches n = 172 100 110 01 0 110 110 90 100 n = 54 100 100 80 90 90 0.436 90 90 110 120 110 100 90 80 80 80 0.14 80 80 n = 309 0. 100 0.076 120 90 E. Arches 0. 120 100 90 80 80 0.036 120 n = 251 110 120 110 100 80 90 0. 0 C. Whorls n = 348 A. Left Slant Loops .0 36 0.01 -0 -0 .0 1 0.001 01 0 36 Average Minutiae Density (Avg. Number Minutiae / Sq. mm) 0 2-mm Grid Cell Minutiae Density Bifurcations 80 90 100 110 120 80 90 100 110 120 Minutiae / Ridge Frequency Ratio • Compared minutiae / ridge count ratios above and below the core for 188 vectorized fingerprints (all pattern types) Above Core - Minutiae: 33 - Ridge Lines: 81 - Minutiae/Ridge Ratio: 0.41 • Paired t-test: – t = -24.525, df = 187 – mean difference = -0.19 – p-value < 2.2e-16 • Difference in minutiae / ridge ratios above and below core is significant with a p < 2.2e-16 Below Core - Minutiae: 63 - Ridge Lines: 100 - Minutiae/Ridge Ratio: 0.63 Summary • Fingerprint analysis is based on spatial associations between minutiae and ridge lines, so GIS-based tools for spatial analysis are a natural extension. • The project-related GIS tools and preliminary results offer promising contributions to the advancement of fingerprint analysis and forensic science in the near future. • Other fingerprint characterization methods not presented: – Thiessen polygons – Ridge Density Maps – Dart Board Minutiae Density Maps – Fingerprint Geometry – Monte Carlo Minutiae Simulation Acknowledgments • National Institute of Justice (Grant Award # 2009-DN-BX-K228) • Western Oregon University • Oregon State Police, Forensic Services Division and ID Services Division This project was supported by Award No. 2009-DN-BX-K228 awarded by the National Institute of Justice, Office of Justice programs, U.S. Department of Justice. The opinions, findings, and conclusions or recommendations expressed in this publication/program/exhibition are those of the author(s) and do not necessarily reflect those of the Department of Justice.