Ping GallivanXiang Gao
Eric Heinen Akarsh Sakalaspur
Automated Coin Grader
Overview
• Introduction
• Technical report
-histograms
-edge Detection
-web Interface
• Conclusion
• Demo
Long Term Goal of Project
• Develop a system that will be used to grade, appraise and authenticate valuable collectibles items such as rare coins providing consistent and repeatable results.
The Need for anAutomated Coin Grader
• Unreliable results from manual grading • Value of the coins • Grading judgment changes from person to
person• Fakes are plentiful• Many different denominations of coins• The rare coin market is dynamic and with
significant changes occurring every week or so
Goals for our project
• Develop an Automated Coin Grading System
• Web based Coin Grading Quiz
Tools Used
• Java
• Java Script
• HTML
• C++
• Imaging Processing Packages
Architectural Designof System Overview
DB
Scanner Image Processor
Output System
Scans Extracts features
Display Grades
Creating Database
• Obtain a Coin Image (.gif)
• 36 Coins Histograms
• 36 Coin Edge Detection Images
•Distance Measurements
Image Processing
•Hue: the color reflected from or transmitted through an object.
•Saturation: Saturation- the strength or purity of a color
•Brightness: Brightness- the relative lightness or darkness of a color
Image Processing Measure Histogram
Obtain statistical data on the scanned pixels in the image in terms of the Hue, Saturation &
Brightness vectors
Distance MatrixThe statistical data collected in step 2 allows us to determine which coins are
similar to others in our database in terms of known grade.
Histrogram Analysis
Coin Grade Processing Results
Web Based Coin Grading Quiz Site
Benefits of the Quiz Site
• Educate and attract new collectors with a fun and interactive web interface
•Acclimate the public and the coin grading industry to the idea of electronic grading
Image Processing Edge Detection
Edge Detection allows us to look at a coin in a 3D view and pickup additional features.
Web Site Results Page
Analysis“..nothing can compare to examining a coin in person. “
Four distinct factors
• Surface Preservation
• Strike
• Lustre
• Eye-Appeal
•Surface Preservation - This includes the presence of bagmarks, hairlines from cleaning or mishandling, and other imperfections, whether mint caused or man made.
•Strike - Refers to the sharpness and completeness of detail, with the normal characteristics of that particular type, date and mint mark taken into account.
•Lustre - This encompasses the brilliance, sheen and contrast of the coin, again taking the normal characteristics of the particular issue into account
•Eye-Appeal - That certain aesthetic appeal that results from the combination of all of the coin's qualities.
Process
•Single image of the coin under defined lighting conditions should be captured in digital form using a high resolution camera.
•Various portions of the captured images are to be computer enhanced to bring out important features of the coin.
•The key regions of the coin need to be examined in great detail to identify, classify, measure, and score all flaws.
•A light flow and reflectance analysis should be used to precisely measure the mirror as well as the inherent lustre of the coin.
Future Work• Expand image processing to include
advanced feature recognition beyond HSB and Edge Detection.
• Increase the database to include a larger sample set and other denominations.
• Design an intuitive user interface for scanning and grading.
• Move closer towards automated grading• Secure funding to cover the costs of
equipment & software required
Future Work
•Key components of the coin including obverse and reverse marks, strike, lustre, eye appeal, mirror, toning, and exceptional conditions need to be considered to arrive at a set of ”expert rules”.
•Expert Rules – Final Grade
Conclusionwhat does the future have in store for the grading of coins?
•Aid the human graders in making a final determination of the grade of the coin
•Computer grading systems can be highly consistent, accuracy of about 90%
•Image archiving will store one or more images of the coin for future reference
•Reduces turn around time and cost
Questions???
&
Demonstration