Attention information based spatial adaptation framework for browsing videos via mobile devices

The limited display size of the mobile devices has been imposing significant barriers for mobile device users to enjoy browsing high-resolution videos. In this paper, we present a novel video adaptation scheme based on attention area detection for users to enrich browsing experience on mobile devices. During video compression, the attention information which refers to as attention objects in frames will be detected and embedded into bitstreams using the supplement enhanced information (SEI) tool. In this research, we design a special SEI structure for embedding the attention information. Furthermore, we also develop a scheme to adjust adaptive quantization parameters in order to improve the quality on encoding the attention areas. When the high-resolution bitstream is transmitted to mobile users, a fast transcoding algorithm we developed earlier will be applied to generate a new bitstream for attention areas in frames. The new low-resolution bitstream containing mostly attention information, instead of the high-resolution one, will be sent to users for display on the mobile devices. Experimental results show that the proposed spatial adaptation scheme is able to improve both subjective and objective video qualities.