结合人眼视觉感知特性的光场图像编码方法

Light field image coding combined with human visual system

光场图像可同时记录场景中光线强度与方向信息,但要求更多的存储、传输资源,因而需要高效的编码方案。提出了一种结合人眼视觉感知特性的光场图像编码方法,实现了端到端的感知光场编码。考虑到在光场编码相同的失真等级情况下,显著性区域的失真更易被察觉,提出光场图像感知编码方法。针对子孔径图像感知冗余,考虑到像素域恰可察觉失真(Just Noticeable Distortion,JND)模型没有关注显著区域特性,构建了结合显著性的JND掩蔽模型;其后,针对每一帧子孔径图像进行考虑人眼感知的自适应码率分配。实验结果表明,在低延时模式下,与高效视频编码(High Efficiency Video Coding,HEVC)方法相比,所提方法在相同的显著性加权峰值信噪比SW-PSNR质量指标下平均节省16.01%的码率,在与人眼主观感受契合度更高的情况下,实现了光场图像编码效率的提升。

Light field image can simultaneously record light intensity and direction information in the scene,but it requires more storage and transmission resources,so that efficient encoding schemes are required.This paper proposes a light field image coding method based on human visual system,achieving end-to-end perceptual light field coding.Considering that under the same distortion level of light field encoding,the distortion in salient region is more easily perceived,a light field image perception coding method is proposed.Aiming at the perception redundancy of sub aper-ture images,considering that the Just Noticeable Distortion(JND)model in pixel domain does not pay attention to the salient region characteristics,a JND masking model combining saliency is constructed;and then,adaptive rate alloca-tion considering human perception is performed for each sub aperture image frame.The experimental results show that in the low latency mode,compared with the High Efficiency Video Coding(HEVC)encoder,the proposed method saved an average bit rate of 16.01%under the same quality index of Significance Weighted Peak Signal-to-Noise Ra-tio(SW-PSNR),it improves the efficiency of light field image encoding while achieving a higher degree of fit with the subjective perception of the human eye.