Method for measuring stereo camera depth （方法测量立体相机的深度）.pdfVIP

Method for measuring stereo camera depth accuracy based on stereoscopic vision Mikko Kytö*, Mikko Nuutinen, Pirkko Oittinen Aalto University School of Science and Technology, Department of Media Technology, Otaniementie 17, Espoo, Finland ABSTRACT We present a method to evaluate stereo camera depth accuracy in human centered applications. It enables the comparison between stereo camera depth resolution and human depth resolution. Our method uses a multilevel test target which can be easily assembled and used in various studies. Binocular disparity enables humans to perceive relative depths accurately, making a multilevel test target applicable for evaluating the stereo camera depth accuracy when the accuracy requirements come from stereoscopic vision. The method for measuring stereo camera depth accuracy was validated with a stereo camera built of two SLRs (single- lens reflex). The depth resolution of the SLRs was better than normal stereo acuity at all measured distances ranging from 0.7 m to 5.8 m. The method was used to evaluate the accuracy of a lower quality stereo camera. Two parameters, focal length and baseline, were varied. Focal length had a larger effect on stereo cameras depth accuracy than baseline. The tests showed that normal stereo acuity was achieved only using a tele lens. However, a users depth resolution in a video see-through system differs from direct naked eye viewing. The same test target was used to evaluate this by mixing the levels of the test target randomly and asking users to sort the levels according to their depth. The comparison between stereo camera depth resolution and perceived depth resolution was done by calculating maximum er