IEEE Trans Image Process. 2017 Dec;26(12):5936-5949. doi: 10.1109/TIP.2017.2740159. Epub 2017 Aug 14.
This paper addresses the problem of designing a global tone mapping operator for rate distortion optimized backward compatible compression of high dynamic range (HDR) images. We address the problem of tone mapping design for two different use cases leading to two different minimization problems. The first problem considered is the minimization of the distortion on the reconstructed HDR signal under a rate constraint on the standard dynamic range (SDR) layer. The second problem remains the same minimization with an additional constraint to preserve a good quality for the SDR signal. Both the distortion and rate are expressed as a function of the spatial gradient in HDR images. Experiments show that the proposed rate and distortion models based on the HDR image gradient accurately predict the real image rate and distortion measures. Experimental results show that for the first minimization, the optimal rate-distortion performances are achieved, and that the second optimization yields the best tradeoff between rate-distortion performance and quality preservation of the SDR signal.
本文针对高动态范围 (HDR) 图像的率失真优化向后兼容压缩，设计了一种全局色调映射算子。我们针对两种不同的用例解决了色调映射设计问题，这导致了两个不同的最小化问题。考虑的第一个问题是在标准动态范围 (SDR) 层的速率约束下，对重建的 HDR 信号的失真最小化。第二个问题与第一个问题相同，但最小化的同时，还需要保持 SDR 信号的高质量。失真和速率都表示为 HDR 图像中的空间梯度的函数。实验表明，基于 HDR 图像梯度的所提出的率失真模型可以准确地预测实际图像的率失真度量。实验结果表明，对于第一个最小化问题，可以实现最佳的率失真性能，而第二个优化则可以在 SDR 信号的率失真性能和质量保持之间取得最佳折衷。
