SPStudio Chris Johnston

What? SPStudio Tool to gather 3D data from digital photographs. Stereo Photogrammetry Give a computer depth perception. Stereo Correspondence The use of 2D image data to determine a point’s location in 3D space. Volumetric Reverse Multiple Correspondence Algorithm Finds corresponding volume. Takes a point in 3D space and determines its location within the images.

Functions Save progress at any time Fully graphical View finalized data set Estimated time of algorithm completion Change image file associations any time before the algorithm is run Change camera information at any time before the algorithm is run Produce a 3D data set that is a reasonable representation of the object captured in the photos Provide a multiple document interface environment

Specifications Development Environment Visual Studio.NET 2003 C# Minimum System Requirements.NET Runtime Environment 256 MB RAM 1.2 GHz processor 32 MB accelerated graphics card with OpenGL support

Why? Current Modeling Methods Require a degree in themselves Vertex by vertex data entry Geometric primitive data entry SPStudio User-friendly Quick No artistic ability required Inexpensive

Who? Students Weekend programmers New companies The artistically or financially challenged

How? Current Algorithms Object Specific Large amount of user input High risk of bad data entry Volumetric Reverse Multiple Correspondence Algorithm Given a volume in 3D space, does this volume correspond to the volume of the object photographed? Small and simple data input Lower chance of bad data entry

Algorithm Data Input User takes photographs of object Must be same distance from object First photo is the reference photo and is treated as taken from 0 degrees Each photo after that must be assigned a degree with regard to the reference photo (clockwise rotation of object)

Example Photos

Silhouette Data Input Method

Algorithm Simplified

Shift Phase

Post Shift

Voxel Representation

Where’s the “any” key? I am a user. You are and application. I shall destroy you! I will enter a word when you ask for a number. I will enter a document when you ask for an image. I will do everything you do not want me to do.

Protecting the User from themselves

More Protection

Even MORE Protection

Are we there yet? Current Issues Refresh fault due to C#’s component threading system.

System Layout

Finalizing Record the intersection data from the 4 shift voxel data sets in a simple format

Issues During Development Having a working prototype doesn’t mean you are almost done! It is hard to be a developer and think like a user. Pass by reference decreases memory usage and increases aspirin usage.