應用於液晶顯示器之可適性區域背光控制顯示器積體電路設計

Block-Based Content Adaptive Backlight Controller VLSI Design for Local Dimming Liquid Crystal Displays

蔡欣儒(Hsin-Ju Tsai)

指導教授 ： 陳世綸

中原大學/電機資訊學院/電子工程研究所/碩士(2016年)

https://doi.org/10.6840/cycu201600752

摘要

本論文提出三種區塊可適性調光設計，用以實現液晶顯示器背光控制器積體電路實現。此演算法基於亮度分析與預測節省能源幅度，並用亮度增強法來補償失真影像，此論文提出三種自適性調節演算法為基於平均亮度、最大亮度和高斯分佈來進行亮度分析。為了提高影像品質，此演算法開法由影像整張運算改由區塊運算取代整幀運算區塊運算。在硬體方面，本論文所提出的這種設計是由0.18微米技術合成，為了減少硬體成本及運算複雜度，利用查表轉換運算來進行運算去減少高位元的乘除法器並且減少運算時間。新的平均值，新的最大值和高斯分佈的方法晶片面積在100 MHz的工作時分別為528,099平方微米、609,960平方微米和630,113平方微米與以前的設計相比，本論文提高了平均35.51分貝、42.78分貝和45.42分貝與降低46.24％、50.78％和48.32％液晶顯示器背光能源消耗晶片面積在100 MHz的工作時為528,099平方微米。

關鍵字

區塊設計 ； 可適性調光 ； 液晶顯示器 ； 背光控制器 ； 自適性調節 ； 高斯分佈 ； 積體電路

並列摘要

In this thesis, three novel hardware-oriented block-based content adaptive backlight control (CABC) algorithms are proposed for VLSI implementation. It composed of a novel backlight dimming algorithm to reduce power consumption of the backlight module on LCDs and a feature contrast enhancement algorithm to compensate the distortion. In this thesis, the adaptive backlight dimming algorithm raises three methods which are the new average, new maximum and Gaussian distribution method. To improve the image quality, the proposed algorithm was developed to be block-based rather than frame-based. The VLSI architecture of this design includes a grayscale operator, a block-base module, a brightness analysis module, a clipped point calculator, a brightness comparator, a brightness ratio calculator, a pixel compensator, and the PWM pulse generator. To reduce hardware costs and improve executing performance, the three table of the 8-bit to 16-bit square computer, the compensation gain factor and the backlight dimming factor were realized by a looking-up-table technique to replace the high-complexity multiple-square-calculators and dividers. The grayscale module was simplified by replacing the multipliers with adders and shifters to further reducing hardware costs. This design was synthesized by a 0.18-μm technology. The new average, new maximum and Gaussian distribution method contain 18.87K, 19.2K and 20.21K gate counts respectively and which are the new average, new maximum and Gaussian distribution methods the three tables of the its core areas are separately
528,099 μm2, 609,960 μm2 and 630,113 μm2, when operating at 100-MHz. Compared with previous designs, this work improved three methods of the average PSNR values by over 35.51 dB, 42.78 dB and 45.42 dB and reduced LCD backlight power consumption by 46.24%, 50.78% and 48.32%.

並列關鍵字

block-based ； content adaptive backlight control ； backlight dimming ； Gaussian distribution ； VLSI ； LCD

參考文獻

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