有機發光二極體顯示器是一種新的顯示技術，且逐漸被廣泛的應用在消費性電子產品。有機發光二極體顯示器有需多特性，尤其是能以較低的功率來顯現色彩。然而在高頻可見光譜，如白色，仍然需要消耗大幅的功率。我們提出一套可保有色相資訊且有效降低功率的視頻調整機制。此方法利用色相、飽和度、亮度值推導出的表示式並結合視頻內容資訊來進行調整。因此，所提的方法可直接針對視頻內容的紅綠藍資訊進行調整。另外此方法利用各畫面之間的信息資訊來減少視頻的計算處理。由實驗數據可知，我們所提的方法最多可降低 73% 的螢幕功率消耗，同時在視覺顯著性上平均能保持0.961。

Displays based on organic light emitting diodes (OLEDs) is an emerging technology that has been widely used in mobile devices. It incorporates a varying power-demand character, which particularly inefficient for displaying bright colors. This thesis proposes a scheme that preserve hue information and reduce power consumption for video sequences on OLED displays based on the pixel dimming transformation. The dimming scheme uses the coefficient derived from the hue-saturation-value (HSV) representation and the luminance of the frame to modify each pixel. Thus, the proposed scheme allows the data adjustment directly on the red, green, and blue intensity of the contents. The temporal information between each frame is adopted to reduce the computation for video sequence processing. According to the measurement of several video sequences on an OLED display, up to 73% of displaying power can be reduced with mean visual saliency index of 0.961.

[1] Google, The Mobile Movement: Understanding Smartphone Users, Google/IPSOS OTX MediaCT, Apr. 2011, [Online]. Available: www.google.com/think/insights.
[2] A. Carroll, and G. Heiser, “An Analysis of Power Consumption in a Smartphone,” in Proc. USENIX Ann. Technical Conf., vol. 14, 2010.
[3] D. shin, Y.Kim, N. Chang, and M. Pedram,“Dynamic Driver Supply Voltage Scaling for Organic Light Emitting Diode Displays,”IEEE Trans. Comput. Aided Des. Integr. Circuits Syst., vol. 32, no. 7, pp. 1017-1030, Jul. 2013.
[4] S. R. P. Silva et al.,“Nanoengineering of Materials for Field Emission Display Technologies,”in Proc. IEE Circuits, Devices and Syst., Oct. 2004, vol. 151, no. 5, pp. 489-496.
[5] S. Uchikoga, “Future Trend of Flat Panel Displays and Comparison of its Driving Methods,”in Proc. IEEE International Symposium on Power Semiconductor Devices and IC's, Naples, Jun. 2006, pp. 1–5.
[6] B. Geffroy, P. L. Roy, and C. Prat,“Organic light-emitting diode (OLED) technology: Materials, devices and display technologies,”Polymer Int., vol. 55, no. 6, pp. 572–582, Jun. 2006.
53[7] M. Dong and L. Zhong, “Chameleon: A Color-Adaptive Web Browser for Mobile OLED Displays,”IEEE Trans. Mobile Comput., vol. 11, no. 5, pp. 724–738, May 2012.
[8] C.-K. Kang, C.-H. Lin, and P.-C. Hsiu, “A Win-Win Camera: Quality-Enhanced Power-Saving Images on Mobile OLED Displays,”in Proc. IEEE Int. Symp. Low Power Electron. Design, Rome, Italy, 2015, pp. 267–272.
[9] C.-S. Chae, H.-P. Le, K.-C. Lee, G.-H. Cho, and G.-H. Cho, “A Single-Inductor Step-Up DC-DC Switching Converter With Bipolar Outputs for Active Matrix OLED Mobile Display Panels,”IEEE J. Solid-State Circuits., vol. 44, no. 2, pp. 509–524, Feb. 2009.
[10] C. Lee and C. Lee and Y.-Y. Lee and C.-S. Kim, “Power-Constrained Contrast Enhancement for Emissive Displays Based on Histogram Equalization,”IEEE Trans. Image Process., vol. 21, no. 1, pp. 80–93, Jan. 2012.
[11] L.-M. Jan, F.-C. Cheng, C.-H. Chang, S.-J. Ruan, and C.-A. Shen,“A Power-Saving Histogram Adjustment Algorithm for OLED-Oriented Contrast Enhancement,”J. Display Technology., vol. 12, no. 4, pp. 368–375, Apr. 2016.
[12] Y.-T. Peng, F.-C. Cheng, L.-M. Jan, and S.-J. Ruan,“Histogram shrinking for power-saving contrast enhancement,”in Proc. IEEE Int. Conf. Image Process., Melbourne, 2013, pp. 891-894.
[13] T.-C. Chang, S. S.-D. Xu, and S.-F. Su, “SSIM-based Quality-on-Demand Energy-Saving Schemes for OLED Displays,”IEEE Trans. Syst. Man Cybern. A., Syst. Hu-mans, vol. 46, no. 5, pp. 623–635, May. 2016.
[14] P. Chondro, and S.-J. Ruan,“Perceptually Hue-Oriented Power-Saving Scheme with Overexposure Corrector for AMOLED Displays,”J. Display Technology., vol. 12, no. 8, pp. 791-800, Mar. 2016.
[15] X. Chen, Y. Chen, and C. J. Xue,“DaTuM: Dynamic Tone Mapping Technique for OLED Display Power Saving Based on Video Classification,”in Proc. of IEEE/ACM DAC, San Francisco, 2015, pp. 1–6.
[16] M. Park and M. Song, “Saving Power in Video Playback on OLED Displays by Acceptable Changes to Perceived Brightness,”J. Display Technology., vol. 12, no. 5, pp. 483–490, May. 2016.
[17] C. C. Yang and J. J. Rodriguez, “Efficient luminance and saturation processing techniques for bypassing color coordinate transformations,”in Proc. IEEE Int. Conf. on Systems, Man, and Cybernetics, Vancouver, 1995, pp. 667–672.
[18] T.-C. Chang and S. S.-D. Xu, “Object-Image Based Quality-on-Demand Energy Saving Schemes for OLED displays,”Electron. Lett., vol. 50, no. 22, pp.1595-1597, Oct. 2014.
[19] D.-H. Lee, Y.-J. Yoon, S.-J. Kang, and S.-J. Ko, “Correction of the Overexposed Region in Digital Color Image,”IEEE Trans. Consum. Electron., vol. 60, no. 2, pp. 173–178, May 2014.
[20] K. He, J. Sun, and X. Tang, “Single image haze removal using dark channel prior,” IEEE Trans. Pattern Anal. Mach. Intell., vol. 33, no. 12, pp. 2341–2353, Oct. 2011.
[21] S. K. Naik and C. A. Murthy, “Hue-preserving color image enhancement without Gamut problem”, IEEE Trans. Image Process., vol. 12, no. 12, pp. 1591-1598, Dec. 2003.
[22] L. Zhang, Y. Shen, and H. Li,“VSI: A Visual Saliency-Induced Index for Perceptual Image Quality Assessment,”IEEE Trans. Image Process., vol. 23, no. 10, pp. 4270-4281, Oct. 2014.
[23] L. Zhang and H. Li, “SR-SIM: A Fast and High Performance IQA Index Based on Spectral Residual,”in Proc. IEEE Int. Conf. Image Process., Orlando, 2012, pp. 1473-1476.
[24] M. R. Luo, G. Cui, and B. Rigg, “The Development of the CIE 2000 Colour-Difference Formula: CIEDE2000,”Color Research Applicat., vol. 26, no. 5, pp. 340–350, Aug. 2001.
[25] G. Sharma, W. Wu, and E. N. Dalal, “The CIEDE2000 Color-Difference Formula: Implementation Notes, Supplementary Test Data, and Mathematical Observations,” Color Research Applicat., vol. 30, no. 1, pp. 21–30, Feb. 2005.
[26] Monsoon power monitor, www.msoon.com/LabEquipment/PowerMonitor.