- This paper presents the summary of the image processing of a vision-based three-axis attitude determination sensor, which observes a solar system oblate body such as a planet or a planet's moon. From the observed image it is possible to extract two independent directions and, consequently, to estimate the three-axis spacecraft attitude. By measuring two independent directions, the sensor can operate in a stand-alone configuration. In this paper, algorithms to determine the required parameters using the observed image are briefly described. Sensitivity is investigated by giving correlation results associated with image translation and rotation, two required process to derive the sensor attitude data.