A Comparative Study of Three Methods for Identifying Individual Tree Crowns in Aerial Images Covering Different Types of Forests

Timber volume is an important parameter in forestry and with the position of each individual tree together with its size this parameter can be estimated with higher accuracy than from estimations made at stand level. In this paper, three existing methods for individual tree crown extraction are compared for different types of forests. The types of forests range from planted forests to dense forests. None of the three methods can alone handle all types of forests with satisfactory result. The most obvious remark is that there is a separation between the methods that can handle dense forests and those which can handle sparse forests. None of the three methods compared in this paper can handle both categories in a satisfactory manner.