JPEG Pleno: Providing representation interoperability for holographic applications and devices

Abstract

Guaranteeing interoperability between devices and applications is the core role of standards organizations. Since its first JPEG standard in 1992, the Joint Photographic Experts Group (JPEG) has published several image coding standards that have been successful in a plethora of imaging markets. Recently, these markets have become subject to potentially disruptive innovations owing to the rise of new imaging modalities such as light fields, point clouds, and holography. These so‐called plenoptic modalities hold the promise of facilitating a more efficient and complete representation of 3D scenes when compared to classic 2D modalities. However, due to the heterogeneity of plenoptic products that will hit the market, serious interoperability concerns have arisen. In this paper, we particularly focus on the holographic modality and outline how the JPEG committee has addressed these tremendous challenges. We discuss the main use cases and provide a preliminary list of requirements. In addition, based on the discussion of real‐valued and complex data representations, we elaborate on potential coding technologies that range from approaches utilizing classical 2D coding technologies to holographic content‐aware coding solutions. Finally, we address the problem of visual quality assessment of holographic data covering both visual quality metrics and subjective assessment methodologies.

Progressive hologram transmission using a view-dependent scalable compression scheme

“…The chrominance format of CGH is set to 4:4:4 with 8bit depth for each color's channel (R, G and B). Since the R/I format allows a better bit-rate allocation than the A/P format [48], it is considered for all the encoding process. Figure 7 shows the numerical reconstructions of the non-compressed holograms for a central viewpoint, i.e.…”

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

“…From the research point of view, having a wide variety of available data is crucial, as stated in Section 3, but, especially for those who approach the study of this imaging technique for the first time, it is also important to establish a clear correspondence between the operations that the software is able to do, and the samples on which these operations can be performed. Holography is an area in which standardization activities are in their initial stages [2], and a standard data representation format is not available yet. Moreover, holography has different application fields such as display, tomography, microscopy, and interferometry and often every application requires specific processing steps that are not necessary or useful for another application.…”

“…The interest in holographic imaging is growing both in academic and industrial areas. The ISO/IEC SC29 WG1 JPEG committee is currently developing a standard for coding different light-field modalities (JPEG Pleno) which comprise the definition of a framework to facilitate the representation of holographicdata [2]. High resolution and wide viewing angles, necessary for realizing high-quality and immersive holographic applications, make holographic imaging very data intensive.…”

Digital holography data compression

“…Despite different data compression approaches have been proposed, no standard solution has been established so far, and further studies are needed to better understand the holographic data features. The ISO/IEC JPEG standardization committee has recently started an activity, named JPEG Pleno, with the aim to explore, among other challenges, the holographic data compression field [44].…”