Reduction of temporal distortion in video coding based on detection of just-noticeable temporal pumping artifact

•A metric of just-noticeable temporal pumping artifact (JNTPA) is formulated.•The proposed metric predicts JNTPA values in correspondence with human perception.•An efficient algorithm based on the JNTPA has been devised for TPA reduction.•The proposed algorithm achieves a more smooth subjective video quality.•The proposed algorithm improves the viewing comfort for the human eye.

At low bit-rates, video coding under the hierarchical prediction structure induces a temporal distortion known as temporal pumping artifact (TPA) when the quantization parameter cascading strategy is used. TPA manifests itself as a pumping effect visually, due to severe quality fluctuations among adjacent pictures, which seriously affects the perceptual quality of a video. In this work, the causes and perception of the TPA is first analyzed. Then a metric of just-noticeable temporal pumping artifact (JNTPA) is formulated based on characteristics of the human visual system. Based on JNTPA, an efficient algorithm has been devised for TPA reduction (denoted as TRA-JNTPA for short). The experimental results have demonstrated that the proposed JNTPA measure is in line with human perception, and compared with JVT-P014, the proposed TRA-JNTPA achieves significant reduction of the TPA with superior subjective video quality at a given bit-rate.