Object Extraction from Colour Cadastral Maps

摘要

In this paper, an object extraction method from ancient colour maps is proposed. It consists on the localization of quarters inside a given cadastral map. The colour aspect is exploited thanks to a colour restoration algorithm and the selection of a relevant hybrid colour model. Objects composing the map are located using a multi-components gradient. To identify quarters, a peeling the onion method is adopted. This selective method starts by separated text and graphics. On the graphic layer, a connected component analysis is carried out through the use of a neighbourhood graph. This graph is smartly pruned to consider only significant areas. Consequently, the quarter boundaries are found using a snake which is a computer-generated curve that moves within an image to fit a given object. The performance of our method is measured up in two steps: Firstly, the colour space selection is assessed according to the colour distinction capacity while being robust to variationsoise then the automatic extraction approach is compared to the user ground truth. Results show the good behaviour of the whole system.