1 / 24

TREES: Computer vision based tree-ring analysis and measurement system.

A C OMPUTER -A SSISTED T REE -R ING C HRONOLOGY C OMPOSITION S YSTEM System Overview B y: James B. Engle Department of Electrical and Computer Engineering at The University of Arizona.

galena-hodges
Download Presentation

TREES: Computer vision based tree-ring analysis and measurement system.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. A COMPUTER-ASSISTEDTREE-RING CHRONOLOGYCOMPOSITION SYSTEMSystem OverviewBy: James B. EngleDepartment of Electrical and Computer EngineeringatThe University of Arizona J. Engle, University of Arizona, ECE-DIAL/LTRR

  2. Table of ContentsSection Slides1. Background - TREES program overview........................ 3-62. Introducing the CROSSDATE program........................... 7-103. Correlation Tool............................................................... 12-144. Composition Tool............................................................. 15-185. Check Tool....................................................................... 19-226. User Help......................................................................... 237. Contribution to Dendrochronology................................... 24 Reference: Engle, James B., A Computer-Assisted Tree-Ring Chronology Composition System, Master’s Thesis, University of Arizona, 2000. J. Engle, University of Arizona, ECE-DIAL/LTRR

  3. TREES: Computer vision based tree-ring analysis and measurement system. • Tree-ring Sample Image Acquisition • Tree-ring Detection and Measurement • Tree-ring Width Standardization • Focus is on a single tree-ring sample. J. Engle, University of Arizona, ECE-DIAL/LTRR

  4. TREESSystem Components J. Engle, University of Arizona, ECE-DIAL/LTRR

  5. A Computer-Assisted Tree-RingChronology Composition System • TREESGraphic UserInterface Tree-Ring Views Skeleton Plot SequentialProcess Steps:1.Capture Frames2. Create Mosaic3. Find Rings4. Measure Rings5. Create Skeleton Plot J. Engle, University of Arizona, ECE-DIAL/LTRR

  6. TREES Program Output:Index Value Time Series • Standardizationis the process of modeling and removing non-climatic variation to reduce absolute tree-ring width measurements to a common relative scale. • Raw tree-ring width measurements are detrended to produce index values. • Index values represent relativevariations in growth and are the basis of comparing one sample’s growth to another. J. Engle, University of Arizona, ECE-DIAL/LTRR

  7. CROSSDATE: A Computer-Assisted Tree-Ring Chronology Composition System • Separate application from TREES. • Output of TREES is input to CROSSDATE. • Works simultaneously with TREES. • Focus is on multiple tree-ring samples. • A tool, not an expert system. J. Engle, University of Arizona, ECE-DIAL/LTRR

  8. Objectives CROSSDATE is a software tool to assist dendrochronologists to: • Determine the dating of a tree-ring sample. • Compose a master chronology for a site from individual samples. • Perform a QC Check to ensure the validity of a master chronology. J. Engle, University of Arizona, ECE-DIAL/LTRR

  9. Requirements • Ability to determine, manually and with computer assistance, the point where two tree ring samples match in time. • Ability to compose master chronologies from individual samples and other master chronologies. • Ability to rigorously check a tentative chronology for correctness. • Ability to determine and review the specific samples from which a master chronology is composed for purposes of returning to the original wood sample. J. Engle, University of Arizona, ECE-DIAL/LTRR

  10. Requirements • Easy to use, intuitive graphic user interface (GUI) that mimics the steps a tree-ring scientist follows when performing manual crossdating. • Ability to exchange data (Import/Export) in common formats to other tree-ring application programs. • Ability to operate on PC and UNIXworkstation hardware platforms. • Ability to operateseamlessly with the TREES program. J. Engle, University of Arizona, ECE-DIAL/LTRR

  11. CROSSDATE Graphic User Interface J. Engle, University of Arizona, ECE-DIAL/LTRR

  12. Correlation ToolMatch two (2) standardized tree-ring samples in time based on relative patterns of variation in growth. Procedure:1. Calculate correlation coefficient (r) for each possible match point.2. Convert r to t-statistic for hypothesis tests.3. Evaluate the significance.4. Rank and display the results. J. Engle, University of Arizona, ECE-DIAL/LTRR

  13. Correlation CoefficientEfficiently computed using Fast Fourier Transform(FFT) and “One-Pass” statistical accumulation. Correlation Coefficient: Statistical Accumulation forStandard Deviation:(Sxx shown, Syy similar) Cross-Correlation via FFT: J. Engle, University of Arizona, ECE-DIAL/LTRR

  14. CROSSDATE Correlation Graph J. Engle, University of Arizona, ECE-DIAL/LTRR

  15. Composition ToolCreates a master chronology from individual samples and other master chronologies after performing pattern matching. • Definition: A master chronology is a composite of individual samples. Composite means the arithmetic average of component samples index values for each year of the entire time period range. J. Engle, University of Arizona, ECE-DIAL/LTRR

  16. Master Chronology • Useful for recording the growth pattern variation for a site over some time period. • Subsequently useful for dating new samples using correlation pattern matching. • International Tree Ring Data Bank (ITRDB) provides a simple format for data exchange. CROSSDATE imports and exports ITRDB format chronology files. • The annual average index value and number of component samples are exchanged with other programs. J. Engle, University of Arizona, ECE-DIAL/LTRR

  17. CROSSDATE Master Chronologies Composedhierarchicallyusingintermediatechronologies. J. Engle, University of Arizona, ECE-DIAL/LTRR

  18. CROSSDATE Master Chronology Display Screen Sample Depth Components J. Engle, University of Arizona, ECE-DIAL/LTRR

  19. Check ToolPerforms extensive checking on each sample component of a master chronology. • Checks performed:1. Date Alignment2. File Date Check3. Statistical Outliers4. Overall Fit5. Segment Fit • Results are available on Graphic Display and as a Text Report. J. Engle, University of Arizona, ECE-DIAL/LTRR

  20. Component QC Check Panel (Graphic Display) J. Engle, University of Arizona, ECE-DIAL/LTRR

  21. Component QC Check Report (Text Report) J. Engle, University of Arizona, ECE-DIAL/LTRR

  22. Component QC Check Report (Text Report) J. Engle, University of Arizona, ECE-DIAL/LTRR

  23. CROSSDATE User Help • HTML User Help Files are distributed with CROSSDATE. • Menu button invokes Netscapebrowser with CROSSDATE help index. • User Help Files may be viewed with any HTML viewer. J. Engle, University of Arizona, ECE-DIAL/LTRR

  24. Conclusion • Contributions to Dendrochronology • Graphic framework for performing tree-ring sample comparison activities. • Uses familiar methods. • Completes the TREES system. • May be extended as new methods are developed. J. Engle, University of Arizona, ECE-DIAL/LTRR

More Related