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Research on Subjective Quality Assessment of Light Field Images

Light field (LF) exerts a positive impact on many multimedia applications, due to its variety of the post-processing. For the sheer size of data volume and the huge difference compared to natural 2D images, many processing methods for such particular type of image have been proposed by researchers, for which the image quality assessment (IQA) research for such LF images (LFIs) is urgently needed. However, the development of the IQA of LFIs is restricted for lack of a database that fully reflects characteristics of LFIs. Therefore, in this paper, we build a perceptual quality assessment dataset including 240 distorted images from 8 source images by adding five distortion types with several distortion levels and obtain the mean opinion score (MOS) of each LF image by a developed subjective experiment. Further, we propose a subjective evaluation method to evaluate the perceptual quality of distorted LFIs. In the experiment, some classical full reference IQA metrics were used on the proposed dataset, and the results provide useful insights for the future development of compression solutions and objective IQA for LFIs.