有機發光二極體 (OLED)是下一代電子產品顯示器的重要技術。 OLED面板已經正在快速應用於行動裝置，如智能手機，平板電腦，計算機等，甚至有望在較大的面板數位電視上使用。 OLED顯示器與液晶顯示器 (LCD)主要不同，在顯示像素發光方式。LCD需要背光模組，而OLED顯示器面板不需背光模組，它的每個R，G和B分量顯示像素具自體發光能力。比較一般應用而言，OLED顯示器比LCD顯示器節省約40％顯示能量，然而，相對於裝置系統其他元件，OLED面板仍然是一個比較耗能的元件。 OLED相較於LCD有以下優點：視角較廣、反應時間較快、無殘影現象、面板厚度較薄、使用溫度範圍較大及發光效率較高; 有以下缺點：使用壽命較短，色彩純度不足及大尺寸開發技術仍待加強。
OLED顯示器的低耗能技術，有幾個系統方法：使用為基礎的控制(usage-based control) 、部分顯示關閉 (partial display turn off) 、顏色重映射 (color remapping)和動態電壓縮放 (dynamic voltage scaling)。色彩重映射對OLED面板的顯示能量有很大的影響。不幸的是，顏色重映射並不具彈性。這通常涉及急劇變化的色調顯示，如使用者圖形界面使用省電色調，使用者未必會接受。另一方面，動態電壓縮放，雖然不會急劇變化的色調顯示，但它需要改變OLED硬體控制模組，並且需要根據電壓的變化，動態進行像素顏色補償，這是使用上限制。
本文將提出OLED即時節能顯示方法，這將基於基於顯示能量的HSV顏色空間的節能方法。具體來說，它允許顯示節能，同時提供滿足基於PSNR，SSIM和 Entrop-SSIM圖像質量評估的個人的視覺要求。本文有以下貢獻：1）提出的即時品質需求下圖像轉換方法對現有行動裝置可達到節能顯示效果; 2）提出的方法提供使用彈性，克服現有OLED節能方法的限制; 3）用黑色背景圖像物件搜索的節能顯示方法，在PSNR=40分貝下，可以減少高達74％的顯示能量; 4）當SSIM為0.9時高品質圖像轉換下，可達16％〜20％的節能顯示效果; 5）以S3智能手機CPU執行節能顯示轉換，能夠處理高達每秒27高清晰度圖像，這表示本文所提出的方法適合用於高品質的影片節能顯示播放。

Organic light-emitting diode (OLED) is the technology utilized for the next generation of flat-panel displays. OLED panels are already making rapid inroads into mobile devices, such as smart phones, tablets, computers, and are even expected for use in larger panel digital televisions. An OLED display is radically different from a Liquid Crystal Display (LCD), in terms of how the display pixels emit light. Unlike an LCD, which requires a backlight module to illuminate through the red (R), green (G), and blue (B) throttling light gates of a pixel, each display pixel in an OLED display panel actively emits its own R, G, and B components of light. Comparatively, an OLED display is about 40% more efficient than an LCD in the consumption of electrical energy for generating the display. However, compared to other components in an OLED display device, the OLED panel is still a relatively energy-hungry component. It places significant strain on the battery of the mobile device and, therefore, constitutes an important issue in the overall energy conservation system of the device. OLED compared to LCD, has the following advantages: wider viewing angle, fast response time, no image retention, the panel thinner, larger operation temperature range and high luminous efficiency. But has the following disadvantages: shorter usage life cycle, lack of color purity, and large-size technology has yet to be developed.
There are several system level low energy techniques dealing with OLED displays: usage-based control, partial display turn off, color remapping and dynamic voltage scaling. Color remapping has a big impact on the OLED panel power consumption. Unfortunately, color remapping is not always feasible. This usually involves drastically changing the color hue or tone of displays such as for GUI and application software screens. On the other hand, the dynamic voltage scaling, while free from the drastic display theme changes and possible for real-time processing, but it requires additional color compensation to compensate the pixels of which the driving currents change under the scaled voltage, it is the usage limitation.
This dissertation will propose serval real-time quality-on-demand energy-saving schemes for OLED display, which is on the basis of power consumption based HSV color space. Specifically, it allows for the implementation of display energy-saving while delivering precise dynamic and real-time color transformation display that meets personal visual requirements based on PSNR, SSIM and Entropy-SSIM image quality assessment. This dissertation has following contributions: 1) the proposed real-time color transformation schemes allow to quality-on-demand save display power consumption for the existing portable device, 2) the proposed schemes provide flexibility to overcome the limitation of the existing OLED energy-saving solutions, 3) the schemes with black background object-image searching save display power consumption up to 74% under the condition PSNR=40 dB predicted, 4) while the SSIM is set to be 0.9, the proposed schemes can reduce up to 16%~20% OLED display power consumption, and 5) the proposed schemes executed by S3 smartphone CPU are able to process up to 27 high-definition images per second, which indicates the proposed schemes are suitable for energy-saving video playback.

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