Video retargeting using non-homogeneous scaling and cropping

To display a video sequence in different display devices with different resolutions and aspect ratios, the video frames should be resized (retargeted) adaptively, whereas the important content of the video sequence should be retained. This is called the video retargeting problem. The proposed video retargeting approach consists of three main stages: preprocessing, optimization, and transformation. In the preprocessing stage, the initial scaling factor map, the saliency measure, and the temporal coherence measure of each video frame will be computed. In the optimization stage, an iterative optimization procedure is used to find the scaling factor maps of individual video frames via an optimization function involving spatial benefit and temporal cost. In the transformation stage, the scaling factor maps of individual video frames are improved by cropping. Then, the retargeted video frames are generated by pixel fusion using the scaling factor maps. Based on the experimented results obtained in this study, the performance of the proposed approach is better than those of five comparison approaches.