A method for improving the interpretation of the surroundings of a UAV, and to a UAV system is presented herein. The method comprises the steps of acquiring an image comprising depth data, and determining a boundary between a first image portion and a second image portion. The second image portion surrounds the first image portion, and the boundary is defined by an interface between first periphery sub-portions and second periphery sub-portions. A difference in depth data between adjacent first periphery sub-portions and second periphery sub-portions is above a first predetermined threshold and/or second periphery sub-portions comprises undefined depth data. The method further comprises determining the area of the first image portion, and if the area of the first image portion is below a second predetermined threshold, determining that the first image portion contains incorrect depth data and deleting and/or adjusting the incorrect depth data contained by the first image portion.