使用多畫面聯合功率及PSNR特性之最佳化背光節能演算法

Optimized backlight power saving algorithm using joint power-PSNR characteristics among multiple frames

董昆憲(Kun-Hsien Tung)

指導教授 ： 林鼎然

中原大學/電機資訊學院/電子工程研究所/碩士(2017年)

https://doi.org/10.6840/cycu201700271

摘要

在本文中，我們提出一種優化背光節能的演算法，演算法使用了在多個畫面中結合功率與PSNR之特性。在現有的技術方法中，只考慮當前的畫面，便可決定最佳的clipping point，並且所有畫面的目標PSNR都相同。因此它們具有相同的功率-PSNR特性。在本文提出的方法中，我們將可以實現更好的功率-PSNR特性，即在不同的畫面中，搭配不同的target PSNR。我們將評估每個clipping point的無效率比，並將其放入演算法設計中。與現有方法相比，本文提出的方法在功率和PSNR的兩個表現方面都較優；相較於其他方法的BD-PSNR和BD-Power，本文提出的方法在每個測試的影片都有較好的表現；BD-PSNR可以平均進步至15.25dB，BD-Power可以平均進步至-23.56%。

關鍵字

背光節能 ； 多畫面 ； 最佳化問題

並列摘要

In this thesis, an optimized backlight power saving algorithm using joint power-PSNR characteristics among multiple frames is proposed. In existing state-of-the-art methods, the optimal decision for clipping point is made only with consideration of current frame, and the target frame PSNR are set the same for all frames. Therefore they have the same power-PSNR performance. In the proposed work, we show that better power-PSNR performance can be achieved by assigning different target frame PSNR for different frames. In the proposed algorithm, the decisions for clipping points associated with all frames are made at once. The inefficiency ratio of each clipping point is evaluated and put into the algorithm design. An optimization problem is formulated, and a solution-search procedure is proposed. Compared with state-of-the-art methods, the proposed work performs better in both aspects of power and PSNR; the BD-PSNR and the BD-Power of the proposed work against all other methods are better for every tested video; the BD-PSNR and the BD-Power can be as high as 15.25 dB on average, and the BD-Power can be as low as -23.56% on average.

並列關鍵字

Backlight power saving ； multiple frames ； optimization problem ； power-PSNR ； BD-PSNR ； BD-Power

參考文獻

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