Digital Holography Database for Multi-perspective Multi-display Subjective Experiment (DHMulti Database)
The DHMulti database is the most comprehensive publicly available annotated database of digital holograms (to this date May 2019). The DHMulti consists of 96 compressed Fourier holograms out of 8 reference holograms which include both computer generated holograms (CGH) and optically recorded holograms (ORH). The dataset is rendered in 3 different display systems including: an state-of-the-art Light-Field screen with 3D resolution of 73 Mpixel and a 2D Eizo standard monitor with 4K UHD resolution (both property of Vrije Universiteit Brussel) and an optical reconstruction holographic-setup (property of Warsaw University of Technology). 120 human subjects participated in the subjective experiments where each compressed hologram was displayed and scored. For each hologram depending on the depth of the scene, multiple focal distances was used to render the hologram. For each focal distance, the center-view (head-on view) and the right-corner view are scored accordingly.
This file contains the original holograms which were used to generate the dataset. The file consists of 8 '.mat' files. All of them include the hologram and other required information for their reconstruction. Reconstruction may be performed in Matlab with the Fresnel_propag.m function as follows:
Fresnel_propag(data.dh, data.pp, data.wlen, data.zrange(1), data.zref), e.g. like:
data = load('opt_Wolf.mat'); figure(); subplot(1,2,1); imagesc(imresize(abs(Fresnel_propag(data.dh, data.pp, data.wlen, ... data.zrange(1), data.zref)), 1024*[1,1])); title('Front'); subplot(1,2,2); imagesc(imresize(abs(Fresnel_propag(data.dh, data.pp, data.wlen, ... data.zrange(2), data.zref)), 1024*[1,1])); title('Rear');
In each zip file you will find compressed versions of the corresponding reference hologram compressed with HEVC (intra mode and x265 implementation), JPEG 2000 (default setting) and WAK in various bitrates (0.25, 0.5, 0.75, 1, 1.5, 2 and 4 bpp).
- OR-Sphere (optically recorded model of CGH-Ball)
Mean Opinion Socres (MOS)
Averaged Mean Opinion Scores
This mat file contains the averaged MOS scores for all three displays. We have calculated the average of the MOS scores per display between center and right corner view.
Since for the hologrpahic display all the information was rendered without any refocussing, and for the non-holographic displays the objects were rendered with the focal point in front or back of the encoded object; the scores for the light field and the 2D display were also averaged over multiple focal distances to be directly comparable with the holographic dispplay.