JNTD: Toward Just Noticeable Frame Rate-Based Temporal Difference for Perceptual Video Coding
Sanaz Nami, Farhad Pakdaman, Mahmoud Reza Hashemi, Shervin Shirmohammadi, Moncef Gabbouj · IEEE Transactions on Circuits and Systems for Video Technology · 2025
Just Noticeable Difference (JND) refers to the maximum level of distortion in an image or video sequence that remains imperceptible to the Human Visual System (HVS). Current JND-based studies predominantly rely on existing datasets, developing models predicting JND levels in terms of Quantization Parameter (QP) or Quality Factor (QF). However, these solutions primarily focus on spatial-based Perceptual Video Coding (PVC) and neglect temporal-based optimization, which highly affects the video bitrate. This paper addresses this limitation by introducing Just Noticeable frame rate-based Temporal Difference (JNTD) to determine the optimal Frame Rate (FR) based on human perception. A novel dataset comprising 50 high frame rate video sequences is collected through subjective assessments. Subsequently, an ensemble method is proposed to predict the JNTD, by leveraging deep and hand-crafted features, for robust prediction. Experimental evaluations include the integration of the proposed method into several codecs (H.264, H.265, H.266, and a new learned codec), showcasing its ability to reduce bitrate without compromising visual quality.