Video frame transmission delay is critical in real-time applications such as online video gaming, live show, etc. The receiving deadline of a new frame must catch up with the frame rendering time. Otherwise, the system will buffer a while, and the user will encounter a frozen screen, resulting in unsatisfactory user experiences. An effective approach is to transmit frames in lower-quality under poor bandwidth conditions, such as using scalable video coding. In this paper, we propose to enhance video quality using lossy frames in two situations. First, when current frames are too late to receive before rendering deadline (i.e., lost), we propose to use previously received high-resolution images to predict the future frames. Second, when the quality of the currently received frames is low~(i.e., lossy), we propose to use previously received high-resolution frames to enhance the low-quality current ones. For the first case, we propose a small yet effective video frame prediction network. For the second case, we improve the video prediction network to a video enhancement network to associate current frames as well as previous frames to restore high-quality images. Extensive experimental results demonstrate that our method performs favorably against state-of-the-art algorithms in the lossy video streaming environment.
翻译:视频框架传输延迟对于在线视频游戏、现场直播等实时应用来说至关重要。 新框架的接收期限必须赶上框架的设定时间。 否则, 系统将缓缓一段时间, 用户将遇到冷冻的屏幕, 导致用户体验不尽人意。 一个有效的办法是在低带宽条件下以低质量传输框架, 例如使用可缩放的视频编码。 在本文中, 我们提议在两种情况下使用丢失框架来提高视频质量。 首先, 当当前框架太晚, 无法在设定最后期限之前( 即丢失) 接收到高分辨率图像, 我们提议使用先前收到的高清晰度图像来预测未来框架。 第二, 当当前收到的框架质量低时, 我们提议使用先前收到的高清晰度框架来增强低质量的当前框架。 对于第一个案例, 我们提议使用一个小型但有效的视频框架预测网络。 在第二个案例中, 我们改进视频预测网络, 将当前框架与前一个框架连接起来, 以恢复高品质图像。 广泛的实验结果显示, 我们的方法会根据低质的图像环境进行流动。