Improved seam carving for semantic video coding

Traditional video codecs like H.264/AVC encode video sequences to minimize the Mean Squared Error (MSE) at a given bitrate. Seam carving is a content-aware resizing method. In this paper, we propose a semantic video compression scheme based on seam carving. Its principle is to suppress non salient parts of the video by seam carving. The reduced sequence is then encoded with H.264/AVC and the seams are represented and encoded with our proposed approach. The main idea is to encode the seams by regrouping them. Compared to our earlier work, the main contributions of this paper are: a new energy map with better temporal robustness, a new way to define groups of seams using k-median clustering, and an improved background synthesis. Experiments show that, compared to a traditional H.264/AVC encoding, we reach a bitrate saving between 10% and 24% % with the same quality of the salient objects.