Low-cost garment-based 3D body scanner

While in the last decade Laser-based technologies became the reference for 3D body scanning, vision-based technologies became more and more important for motion capture. We are now proposing a mixed approach, based on passive vision technology and able to scan 3D human bodies, as well as capturing motion. In this paper we will present a low-cost multi-camera body scanning system based on a special wearable garment. The garment is a black suit with colored markers, about 3000, uniformly distributed on a square grid all over the body of the subject. Each colored marker is uniquely identified by an ID based on the color of the marker itself and its 8 neighbors. The sequence of 9 color was studied to be unique (no repetitions), independent to rotation (unique starting marker from which to read the color sequence) and non symmetrical (color sequence is unique read either in clockwise and anti-clockwise direction). This allows to deal with thousands of points with no matching outliers. System is composed by 2 up to 12 RGB cameras in order to perform single limb or full body scanning. System calibration is performed in a single step semi-automatic procedure. Synchronous images acquisition is guaranteed by a triggering device, avoiding problems of subject moving during acquisition. Uniform illumination is assured by 6 neon lamps with high frequency electrical ballast. With this system is possible to achieve an accuracy of 1mm on a planar surface.