A practical comparison between Zhang's and Tsai's calibration approaches

With the rise of affordable processing power and off-the-shelf apparatus supporting 3D imaging, there is a growing need for reliable and fast calibration tools, enabling timely accurate data gathering. When confronted with a choice of camera calibration tools, Zhang's and Tsai's are not only the most cited, but also the most widely available solutions. Zhang's calibration is often chosen by default, based on the assumption that it is more accurate. However, it typically involves extensive manual data gathering when compared to the Tsai approach. Here, we demonstrate that there is no significant accuracy gain between Tsai's or Zhang's approach in terms of stereo matching, given the variety of readily available 3D devices tested. Further to this, the trade-off between measurement accuracy compared to setup and data acquisition time is decisively in favour of Tsai. This paper also covers a new algorithm for the extraction of points from images of checkboards attached to calibration objects.