Thumbnail extraction for HEVC using prediction modes

The existing thumbnail extraction method generates a thumbnail by reducing the reconstructed frame after a full decoding process. This method is complex and requires considerable time, particularly for higher resolution video. To alleviate these issues, a fast thumbnail extraction method which utilises an intra-prediction mode for high-efficiency video coding (HEVC) is presented. The proposed method reconstructs only the 4×4 boundary pixels needed for a thumbnail image based on the intra-prediction mode. Experimental results indicate that the proposed method significantly reduces the computational complexity and extraction time for a thumbnail image. The visual quality of thumbnail images obtained with this method does not differ significantly from that of images extracted after a full decoding process.