A Study on the 4D Sparsity of JPEG Pleno Light Fields Using the Discrete Cosine Transform

In this work we study the 4D sparsity of light fields using as main tool the 4D- Discrete Cosine Transform. We analyze the two JPEG Pleno light field datasets, namely the lenslet-based and the High-Densi ty Camera Array (HDCA) datasets. The results suggest that the lenslets datasets exhibit a high 4D redundancy, with a larger inter-view sparsity than the intra-view one. For the HDCA datasets, there is also 4D redundancy worthy to be exploited, yet in a smaller degree. Unlike the lenslets case, the intra-view redundancy is much larger than the inter-view one. The results and conclusions of this first study for light field imaging may have a strong impact on the current and future design of efficient codecs for this type of emerging data, notably in the context of the JPEG Pleno standard.