Subjective quality assessment of numerically reconstructed compressed holograms

Abstract

Recently several papers reported efficient techniques to compress digital holograms. Typically, the rate-distortion performance of these solutions was evaluated by means of objective metrics such as Peak Signal-to-Noise Ratio (PSNR) or the Structural Similarity Index Measure (SSIM) by either evaluating the quality of the decoded hologram or the reconstructed compressed hologram. Seen the specific nature of holograms, it is relevant to question to what extend these metrics provide information on the effective visual quality of the reconstructed hologram. Given that today no holographic display technology is available that would allow for a proper subjective evaluation experiment, we propose in this paper a methodology that is based on assessing the quality of a reconstructed compressed hologram on a regular 2D display. In parallel, we also evaluate several coding engines, namely JPEG configured with the default perceptual quantization tables and with uniform quantization tables, JPEG 2000, JPEG 2000 extended with arbitrary packet decompositions and direction-adaptive filters and H.265/HEVC configured in intra-frame mode. The experimental results indicate that the perceived visual quality and the objective measures are well correlated. Moreover, also the superiority of the HEVC and the extended JPEG 2000 coding engines was confirmed, particularly at lower bitrates.

Compression of digital holographic data: an overview

“…A comparison with H.264/AVC [25] is also made, demonstrating the superiority of H.265/HEVC in this context. Similarly in [32], it is reported that H.265/HEVC provides competitive subjective quality when configured in intra-frame coding mode for holographic images.…”

“…However, given the different nature and characteristics of holograms when compared to images, the use of these measures is not validated and justified. Moreover, subjective experiments are also needed to better understand the perceptual aspects related to the viewing of holograms [32]. This, in turn, would enable the development and validation of objective measures suitable for this type of content.…”

Performance Evaluation of Sparseness Significance Ranking Measure (SSRM) on Holographic Content

“…In the latter, the core similarity formula of SSRM was replaced with the tested VSM instance. All methods were tested on the complex wavefield of 96 holograms from the INTERFERE-I database [6]. The Mean Opinion Scores (MOS) of the database, which was acquired from human subjects who viewed the reconstructed holograms, were used as reference.…”

Recent Advances in the Processing and Rendering Algorithms for Computer-Generated Holography

“…Due to the lack of high-performance holographic displays, other types of displays are used in these experiments, such as autostereoscopic [25], and light field [26]. Moreover, conventional 2D displays are often adopted for experimenting image reproduction schemes for analyzing the scene from different perspectives and reconstruction distances [27][28][29]. In these cases, the rendering and the image-quality evaluation processes are often carried out with computerized simulations.…”