Appraisal of 3 D Data Conversions and Visualization

Appraisal of 3 D Data Conversions and Visualization Software Packages Peter Bajcsy, Ph. D - Research Scientist, NCSA - Adjunct Assistant Professor ECE & CS at UIUC - Senior Associate Director Center for Humanities, Social Sciences and Arts (CHASS), Illinois Informatics Institute (I 3), UIUC National Center for Supercomputing Applications University of Illinois at Urbana-Champaign Date: January 21 st, 2009

Acknowledgement • This research was partially supported by a National Archive and Records Administration (NARA) supplement to NSF PACI cooperative agreement CA #SCI-9619019. • The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the National Archive and Records Administration, or the U. S. government. • Contributions by: Peter Bajcsy, Kenton Mc. Henry, Rob Kooper, Michal Ondrejcek, William Mc. Fadden, Sang. Chul Lee, David Clutter and Alex Yahja Imaginations unbound

Outline • Introduction • Problem Formulation • Approach • Prototype Solution -Polyglot • Conclusions

Why Appraisal of 3 D Digital Data? • Preservation of cultural heritage • Museums, Libraries • Preservation of engineering drawings • Companies: Boeing, John Deere, GM • Government agencies: NASA, Do. D • Preservation of architectural designs • Construction and architecture firms • Preservation of simulation results • Companies: Caterpillar, Ford • Government agencies: EPA, FEMA, Do. D • Preservation of medical data • Companies: GM • Government agencies: Do. D Imaginations unbound

How To Share 3 D Data? • Many File Formats • Complex & Proprietary • Standards (adoption & implementation) • Packaging • One file • Many files • Embedded in a container(e. g. , PDF, HDF) Imaginations unbound

How to Manage 3 D File Formats?

How to Compare and Relate 3 D Data? • Example Data: Torpedo Weapon Retriever 841 • 784 existing 2 D image drawings and 73 3 D CAD models • How to establish relationships among the 3 D CAD models and 2 D image drawings during a product lifecycle? Hypothetical Distribution of 3 D CAD models for TWR 841 Imaginations unbound

How to Design Scalable Appraisal Approaches? • Scalability of appraisals with increasing heterogeneity of information, dimensionality of data and volume of electronic records • How should appraisal process change as 3 D data is added to file containers? • How should appraisal process change as 3 D+time, 2 D+spectrum, 3 D+time+spectrum, n. D, … • How should appraisal operations be designed to accommodate growing volume of electronic records? Imaginations unbound

Problem Formulation Imaginations unbound

Basic Archival Appraisal Questions • Are the 3 D formats well formed? • Can we identify a minimal set of information to preserve? • Is there an optimal format to convert to? • Can we quantify 3 D noise introduced during conversions? • Can we quantify differences in renderings?

Current Focus on 3 D Data Conversions 3 D file format conversions are inevitable since • (a) various software packages support importing and exporting different file formats, • (b) many file formats are retired or deprecated over time, • (c) the cost of preserving the existing large number of file formats is too high. There is a need to understand the impact of 3 D data conversions and the quality of the used conversion and visualization software with respect to information preservation. Imaginations unbound

A Subset of Conversion Related Problems • Problem #1: Appraisal of conversion paths for a given pair of source and target file formats • Problem #2: Appraisal of conversion software • Problem #3: Decision support for a target file format selection • Problem #4: Decision support for information preservation metrics Imaginations unbound

Approach Imaginations unbound

Methodology • Design a graph model of the conversion space • Assign characteristics to nodes and edges of the graph • Find all paths that connect source and target nodes of the graph • Evaluate dissimilarity metrics and computational costs • Analyze and appraise accordingly • Optimally process for preservation Imaginations unbound

Graph Model of Conversion Space Imaginations unbound

Graph Nodes: 3 D File Format Survey From www. turbosquid. com ~ 3 D market place

Graph Oriented Edges: 3 D Software Survey Adobe 3 D Reviewer

Dissimilarity Metrics (Work in Progress) • 2 D histograms, e. g. , spin images, • 3 D light fields, e. g. , visual hull, • metadata, e. g. , header information and material properties, • appearance, e. g. , Spin Images [Johnson, PAMI ‘ 99] screen snapshots, …. . - Construct 2 D histograms for each vertex: - a: distance to plane represented by vertex • . normal • . - b: distance to vertex on this plane - Cluster histograms for each model • . - Compare using Euclidean distance Imaginations unbound

Observations: Conversion of X 3 D to STEP to X 3 D Software: X 3 d. To. Vrml 97 X 3 D WRL Software: A 3 D Reviewer Software: A 3 D Reviewer STEP Nothing! Vrml 97 To. X 3 d WRL X 3 D

Observations: STP to X 3 D to STP A 3 D Reviewer STP Vrml 97 To. X 3 d. To. Vrml 97 X 3 D WRL A 3 D Reviewer WRL STP

Prototype System: Polyglot Imaginations unbound

Current Components of Polyglot • Input/Output Graph • Around 140 file formats (graph nodes) • Seven open source software packages (Blender 2. 46, Cyberware Ply. Tool (iplytool-071024), K 3 D 0. 6. 7, VTK 5. 2. 1, Wings 3 D 0. 99. 02, NIST's Vrm 97 To. X 3 d v 1. 0, NIST's x 3 dv 2) • One commercial package (Adobe 3 D Reviewer) • Conversion Service • Scripted execution • Visualization Service Imaginations unbound

Input/Output Graphs Adobe 3 D Reviewer

Input/Output Graphs Several converters

Shortest Path From Input/Output Graphs Shortest Path

Conversion Service • Challenges with conversion software: • No application programming interfaces (API) for import and export functionality in software packages • Software packages are closed source • Software packages are user interface driven • Approach: The conversion is automated by using the Windows Auto. Hot. Key scripting language • http: //www. autohotkey. com/ • Limitations: Only one conversion can be executed at the same time with one software package due to license issues Imaginations unbound

Polyglot as a Web Service: Upload/Convert/Download View after downloading using a Desktop Tool Imaginations unbound

Polyglot as a Web Service: Find Mapping • Specify Source and Target File Format Imaginations unbound

Polyglot as a Web Service: Display/Interact/Visually Compare Imaginations unbound

Conclusions Imaginations unbound

Current Status • For us, Polyglot is a research prototype that serves as a foundation for addressing basic archival appraisal questions • Noise introduced by conversions • Quality control • Appraisal scalability • There is a value in our better understanding of computational and storage costs associated with preserving 3 D data • Our current work also enables addressing the questions introduced at the beginning, for example, discovering relationships and 3 D comparisons (work in progress) Imaginations unbound

Collaboration Areas with PRONOM/DROID/JHOVE Teams • 2 D Image (JPEG) • 3 D Data (IGS) Imaginations unbound

Questions • Project URL: http: //isda. ncsa. uiuc. edu/NARA/index. html and http: //isda. ncsa. uiuc. edu/Comp. Tradeoffs/ • Publications – see our URL at http: //isda. ncsa. uiuc. edu/publications • Peter Bajcsy; email: pbajcsy@ncsa. uiuc. edu