HEVC-based light field image coding with bi-predicted self-similarity compensation

This paper proposes an efficient light field image coding (LFC) solution based on High Efficiency Video Coding (HEVC). The proposed light field codec makes use of the self-similarity (SS) compensated prediction concept to efficiently explore the inherent correlation of this type of content. To further improve the coding performance, a bi-predicted SS estimation and SS compensation is proposed, where the candidate predictor can be also devised as a linear combination of two blocks within the same search window. In addition, an improved vector prediction scheme is also used to take advantage of the particular characteristics of the SS prediction vectors. Experimental results show that the proposed LFC scheme is able to outperform the benchmark solutions with significant gains.info:eu-repo/semantics/acceptedVersio

Light field image coding based on hybrid data representation

This paper proposes a novel efficient light field coding approach based on a hybrid data representation. Current state-of-the-art light field coding solutions either operate on micro-images or sub-aperture images. Consequently, the intrinsic redundancy that exists in light field images is not fully exploited, as is demonstrated. This novel hybrid data representation approach allows to simultaneously exploit four types of redundancies: i) sub-aperture image intra spatial redundancy, ii) sub-aperture image inter-view redundancy, iii) intra-micro-image redundancy, and iv) inter-micro-image redundancy between neighboring micro-images. The proposed light field coding solution allows flexibility for several types of baselines, by adaptively exploiting the most predominant type of redundancy on a coding block basis. To demonstrate the efficiency of using a hybrid representation, this paper proposes a set of efficient pixel prediction methods combined with a pseudo-video sequence coding approach, based on the HEVC standard. Experimental results show consistent average bitrate savings when the proposed codec is compared to relevant state-of-the-art benchmarks. For lenslet light field content, the proposed coding algorithm outperforms the HEVC-based pseudo-video sequence coding benchmark by an average bitrate savings of 23%. It is shown for the same light field content that the proposed solution outperforms JPEG Pleno verification models MuLE and WaSP, as these codecs are only able to achieve 11% and -14% bitrate savings over the same HEVC-based benchmark, respectively. The performance of the proposed coding approach is also validated for light fields with wider baselines, captured with high-density camera arrays, being able to outperform both the HEVC-based benchmark, as well as MuLE and WaSP.info:eu-repo/semantics/publishedVersio