  Graph-based Light Field coding using the concept of super-rays is powerful to
exploit signal redundancy along irregular shapes and achieves good energy
compaction, compared to rectangular block -based approaches. However, its main
limitation lies in the high time complexity for eigen-decomposition of each
super-ray local graph, a high number of which can be found in a Light Field
when segmented into super-rays. This paper examines a grouping scheme for
super-rays in order to reduce the number of eigen-decomposition times, and
proposes a novel coding architecture to handle the signal residual data arising
for each super-ray group, as a tradeoff to achieve lower computational time.
Experimental results have shown to reduce a considerable amount of decoding
time for Light Field scenes, despite having a slight increase in the coding
bitrates when compared with the original non-grouping super-ray -based
approach. The proposal also remains to have competitive performance in Rate
Distortion in comparison to HEVC-based and JPEG Pleno -based methods.
