A low cost 3D shape measurement method based on a strip shifting pattern

Abstract

We present a simple, low cost but fast 3D shape measurement method. There is no limitation on the object’s material and texture. We use a projector to project a strip shifting pattern on the object, and a digital camera to record videos of the scene. The distortion of the strip shadow on the object is used to get the object’s 3D information. A novel space–time edge finding method is introduced to position the shadow edge accurately. This edge finding method overcomes the effect of inter-reflection and high light. Using this space–time information, we can calculate the pixels’ 3D coordinates. To get the 3D shape of an object with black texture, we improve the black strip pattern to a 3-color strip pattern. The bad data are filtered by a post-processing 3D filter, which makes full use of the neighborhoods’ geometric constraints and the view point constraint. Meanwhile, our measurement method is fast, regardless of the complexity of the shape.