帧速率上转换主要是用来实现两个不同帧率视频扫描格式之间的转换。它可以应用于HDTV和低比特码率编码等应用场合。将场景检测引入到帧率上转换方法中,根据视频内容的变化来检测场景的变换,然后自适应地选择内插(Interpolation)/外推(Extrapolation)的方法,从而解决了传统运动补偿内插法针对序列剧烈运动或场景切换难以处理的问题。同时,结合残差能量的大小和运动矢量的相关性对运动矢量的可靠性进行分类,对不可靠运动矢量采用可变块大小运动估计进行重新搜索,不断更新运动矢量,逐步消除由于运动矢量的不准确带来的方块效应和边缘模糊现象。实验结果表明,算法较传统的插值算法对内插图像的主观质量和客观质量都有所提高。
Frame rate up conversion ( FRUC ) is a conversion process between any two display formats with different frame rates. It can be used in HDTV application and in low bandwidth video coding. In this paper, a scene change detection method is proposed to detect whether the scene has changed. If the scene change occurs, the extrapolation technique will be used, otherwise, the interpolation will be chosen. Second, a motion vector processing method is adopted to correct and refine the unreliable motion vectors with variable block sizes, so the visual artifacts due to incorrect motion vectors can be eliminated and the object boundaries and structure information can be preserved. Experimental results show that the proposed algorithm provides good subjective and objective quality.