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.

中文翻译：

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基于混合数据表示的光场图像编码


本文提出了一种基于混合数据表示的新型高效光场编码方法。当前最先进的光场编码解决方案要么对微图像要么对子孔径图像进行操作。因此，正如所证明的那样，光场图像中存在的固有冗余没有得到充分利用。这种新颖的混合数据表示方法允许同时利用四种类型的冗余：i）子孔径图像空间内冗余，ii）子孔径图像视图间冗余，iii）微图像内冗余，以及iv）内部空间冗余。相邻微图像之间的微图像冗余。所提出的光场编码解决方案通过在编码块的基础上自适应地利用最主要的冗余类型，允许多种类型的基线的灵活性。为了证明使用混合表示的效率，本文基于 HEVC 标准提出了一组与伪视频序列编码方法相结合的高效像素预测方法。实验结果表明，当所提出的编解码器与相关的最先进基准进行比较时，平均比特率节省是一致的。对于小透镜光场内容，所提出的编码算法优于基于 HEVC 的伪视频序列编码基准，平均比特率节省了 23%。结果表明，对于相同的光场内容，所提出的解决方案优于 JPEG Pleno 验证模型 MuLE 和 WaSP，因为与相同的基于 HEVC 的基准相比，这些编解码器只能分别实现 11% 和 -14% 的比特率节省。 所提出的编码方法的性能还针对使用高密度相机阵列捕获的具有更宽基线的光场进行了验证，能够超越基于 HEVC 的基准以及 MuLE 和 WaSP。