MobiUP: An Upsampling-Based System Architecture for High-Quality Video Streaming on Mobile Devices
Nowadays, mobile video streaming enables people to access digital content, such as online TV shows, music videos, sports reports, and news programs, anytime, anywhere. However, current streaming services in mobile networks are subject to the available wireless bandwidth shared among many users and can only provide videos with limited resolutions. Moreover, on recently developed high-resolution mobile devices, such as iPhone, Google Nexus One, Nokia N97, and SonyEricsson X10, the resolution of video streaming is much lower than the devices can actually support. As a result, existing video upsampling schemes usually introduce visual artifacts. In response to the above problem, we bridge the resolution gap between streaming videos and client screens, and propose a novel upsampling-based system architecture, called MobiUP, to enable high-quality video streaming onto mobile devices. To avoid modifying existing codecs for video streaming, MobiUP upsamples videos with decoded frames and appends a limited amount of metadata to the streaming videos for facilitating high-quality and real-time conversion from low resolution to high fullscreen resolution on the client side. In other words, the proposed upsampling architecture complements current systems. Therefore, MobiUP is generic and flexible, and it can be implemented easily on mobile devices for practical use. The implementation results demonstrate that, although the appended metadata is less than 8% of the total transmitted data, it improves the quality of the upsampled video significantly. Meanwhile, the computation time of MobiUP Client is close to that of bilinear upsampling algorithms implemented on mobile devices.