New technique for embedding depth information in captured images using light containing invisible high-frequency patterns

We present a new technique for capturing images where depth information on an object is invisibly and simultaneously embedded in its 2-D image when its image is taken with a camera. An object is illuminated by light that contains invisible patterns whose characteristics change depending on depth; therefore, the images of objects captured with the camera also invisibly contain their depth information. This invisible information on depth can be extracted by appropriate image processing from the captured images. Images taken with this technique can be treated as conventional 2-D images because the image format is for conventional 2-D images. 3-D images can be constructed by abstracting depth information embedded in the images. We carried out experiments using periodical patterns whose pattern pitch were under the revolving power of human vision and whose spatial frequency changed depending on depth. We demonstrated that the depth map on a captured image could be produced by obtaining the frequency of the periodical pattern in the image using a discreet Fourier transform.