3D Data - What comes next?

Sebastian Schröder (MPIB) and Jörg Kantel (MPIWG),
November 12, 2009

• MPIWG: 3D data representing cuneiform tablets
• MPIB: 3D data produced from CRT-scans and the threedimensional presentation of brain activities

We want this in 3D!

• 3D data are given (in our case: PLY or VRML formats)
• 3D data are too big (more then 120 MB)
• Therefore it is nearly impossible to show them on the web
• Loading such data locally in a viewer also makes problems

• There are many different formats used by different applications
• this leads to isolated solution for presenting, archiving, and manipulating the data

• One open format for archiving
• One (open) format for presenting the data on the web as well as on the desktop
• One format for data processing and exchange

Fragebogen?

• Simple linking to metadata
• (integrated in the 3D dataset or stored separately?)

• Open archive format: PLY, VRML
• Format for presentation: PDF, Flash or QuickTime VR
• Format for processing and exchanging data: Cinema4D, an Autodesk format such as 3ds-Max (.3ds), or X3D (the W3C standard)

• Creating thumbnails for the web
• The possibility of downloading in full resolution
• Presentation using a desktop viewer

• OptoView (Fa. Breuckmann)
• Free as in free beer (not open source)
• Reads PLY
• The possibiliy of setting multiple lights easily
• Sufficiently fast
• Windows only

MeshLab is a open source viewer for Windwos, Linux, and MacOS X (Intel only)

• Not really usable for big Meshes (Thanks, Matteo!)
• Reads PLY
• Only one light

• There are problems reading the PLY format into Cinema 4D
• The computer crashes when reading PLY files

• Next approach:
• Converting PLY to VRML using Cinema 4D
• Program hangs during the convertion process (possibly due to the file size)

• Next approach:
• Converting PLY to PDF using Acrobat Professional Extended 9
• Computer crashes (out of memory)

• Next approach:
• The Breuckmann software converts PLY to VRML extremely fast and without problems

• Next approach:
• Converting VRML to PDF using Acrobat Professional Extended 9
• Again »out of memory« using a computer with 6 GB of main memory
• Only a computer with a 64 Bit system and 20 GB main memory could be used successfully

• The problem still exists that textures seem to be systematicelly ignored (we are elaborating the problem)

• Next approach:
• Importing VRML into Cinema 4D
• Cinema 4D reads VRML files without any problems
• Our guess: Since Cinema4D has been developed for movies and animations it is better prepared for reading big files than other tools

• Cinema 4D offers many import, export, and conversation facilities
• But: Cinema 4D looses the textures (colours)

• If we could manage Cinema 4D to import the VRML files with textures, then we would have a good starting point for the export in various other formats (we are working to fix that problem)

• Next approach: Converting files from Cinema 4D to QuickTime VR
• Needs a lot of computing power but Cinema 4D is able to use all existing cores

• Advantage: Very small files: 160 MB VRML is compressed to 4 MB PDF
• Therefore, PDF provides a good basis for the representation on the web
• There are free viewers and free plug-ins for all common browsers
• Offers the possibility to set one light only, but it can be coloured

• Very slow on older Macintosh computers (PPC architecture)
• PDF has the possibility to attach metadata to every 3D point
• nearly lossless compression due to the real-time rendering engine

(with coloured light)

• average file size: 160 MB VRML is compressed to a 20 MB QuickTime VR Movie
• QuickTime VR looses information due to pre-rendering the images and also due to the codecs
• QuickTime plug-in available for all Windows and MacOS X browsers
• No possibility to set any lights. But there is a standard light source with pre-rendered light and shadow sequences
• QuickTime Panorama provides the possibility for 360°-movies (not relevant for cuneiform tablets)

• FreeWRL is a free (as free as in freedom) desktop viewer for VRML/X3D. It runs under Linux and MacOS X. A port for Windows is since a long time »in preparation«.
• FreeWRL is at the moment the only VRML viewer that displays the textures.

• As far as we know there are currently only VRML browser plug-ins for Windows
• But our VRML files are in any cas to big for the web
• Therefore our approach for using VRML files (as for PLY files) is to offer the possibility to download them in order to use a desktop viewer

• Google SketchUp
• 3D Studio Max
• AutoCAD products (DXF)
• Flash-3D-Engine for 3D-web-»thumbnails«

• Presenting the two-dimensional 6-side view on the web
• Simultaneously presenting a 3D-»thumbnail«
• Offering downloads as PLY and VRML files
• Providing metadaten separately as XML file

• Do you have any further ideas or suggestions?

• Thanks for your attention
• Back to wiki view