Aircraft Recognition in High-Resolution Satellite Images Using Coarse-to-Fine Shape Prior

Automatic aircraft recognition in high-resolution satellite images has many important applications. Due to the diversity and complexity of fore-/background, recognition using pixel-based methods usually does not perform well. In this letter, we propose a new method integrating the high-level information of a shape prior, which is considered as a coarse-to-fine process. In the coarse stage, the pose of an aircraft is roughly estimated by a single template matching with a defined score criterion. In the fine stage, we derive a parametric shape model by applying principal component analysis and kernel density function, which have good effects on both dimension reduction and sample space description; then, a new variational formulation combining region information and a shape prior is proposed to segment the object using a level set method. Finally, the parameters of the segmentation result are directly applied to verify aircraft type with two <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">k</tex></formula> -nearest neighbor steps. Experiments on QuickBird images demonstrate the robustness and accuracy of the proposed method.