Active 3D shape acquisition using smartphones

In this paper, we propose an active 3D shape acquisition method based on photometric stereo using smartphone's camera and flash. A pair of smartphones collaborates as the master and slave, in which the slave projects illumination from different locations while the master captures the images and processes photometric stereo algorithm to reconstruct 3D shape. In order to reduce the error, the smart-phone's camera is calibrated to overcome the effect of lens distortion and nonlinear camera sensor response. We apply SURF feature matching and five-point algorithm to estimate the relative pose between the master and slave smart-phones. Then the lighting direction is estimated to run photometric stereo algorithm. All procedures are implemented on an off-the-shelf smartphone. Experimental result shows that the proposed system enables us to use smartphone as a 3D shape capturing device with low cost and reasonable quality.