Perceptual quality of video with quantization variation: A subjective study and analytical modeling

This work investigates the impact of temporal variation of quantization stepsize (QS) on perceptual video quality. Among many dimensions of QS variation, as a first step we focus on videos in which two QS´s, alternate over fixed intervals. We present subjective test results, and analyze the influence of several factors (including the QS difference, QS ratio, changing intervals, and video content). According the observation and data analysis, we propose analytical models that relate the perceived quality with the two QS´s. Such quality assessment and modeling are essential in making video adaptation decisions when delivering video over dynamically changing wireless links.