基於手機平台之節能式自動背光和影像處理

Energy-Saving Automatic Backlight and Image Processing on Mobile Phone Platform

葉建良(Chien-Liang Yeh)

指導教授 ： 李仁貴

國立臺北科技大學/機電學院/電腦與通訊研究所/碩士(2011年)

摘要

近幾年來，手機已成為生活中不可或缺的產品，未來更會將遊戲、應用程式、數位電視整合在智慧型手機裡，人們使用手機的時間只會越來越長，如何讓人們舒適的長時間觀看手機畫面，是未來必須面臨的課題。

基於人眼特性，環境光源亮度和背光亮度必須成正比才能讓人眼感到舒適。本論文將會使用智慧型手機，統計出人眼在各種不同環境光源下感到最舒適的背光亮度，我們會將統計資料應用在自動背光，且計算出節能效果。由於人眼觀看相同的影像會因不同的背光亮度而感覺到太亮或太暗，人眼若感覺太亮，則會刺眼且容易疲勞，人眼若感覺太暗，則不容易看清楚畫面。

本論文提出一個數位影像處理，我們將使用亮度保持雙直方圖均衡法來提升影像對比度，同時基於環境光亮度來調整亮度保持雙直方圖均衡法的權重，以提高人眼觀看手機影像的品質。

關鍵字

自動背光 ； 影像處理 ； 亮度保持雙直方圖均衡法

並列摘要

In recent years, the mobile phone has already become the indispensable products. Games, application programs and digital televisions will be integrated into the mobile phone in the future, and people will spend more and more time to use it. People watch the mobile phone's monitor comfortably for a long time, it will be our topic.

On the basis of the characteristic of human eye, in order to let human eye feel comfortable, the ambient illuminations and backlight brightness must be proportional. This thesis will use smart phone to gather statistics, find which backlight brightness is the most comfortable for human eye under different ambient illumination. We will apply the statistic to automatic backlight brightness, and also calculate the energy conservation effect.When LCD screen backlight too bright, it will cause people dazzle and apt to tired, and oppositely, when LCD screen backlight too dark, it will cause people watch the picture not cleanly.

This thesis proposes a digital image processing method. We will use Brightness Preserving Bi-Histogram Equalization(BBHE) to improve the image contrast, and adjust the parameter of Brightness Preserving Bi-Histogram Equalization, it make the human eye feel image quality will be improved.

並列關鍵字

Automatic backlight ； Image processing ； Brightness Preserving Bi-Histogram Equalization (BBHE)

參考文獻

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