Fast Image Enhancement System for Elderly Person

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K00240
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Perceptual information processing
• Research Institution: Yamaguchi University
• Principal Investigator: Noriaki Suetake 山口大学, 大学院創成科学研究科, 教授 (80334051)
• Co-Investigator(Kenkyū-buntansha): 内野 英治 山口大学, 大学院創成科学研究科, 教授 (30168710) ; 田向 権 九州工業大学, 大学院生命体工学研究科, 准教授 (90432955)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 高齢者視覚変化モデル / 画像・映像強調アルゴリズム / 画像情報処理

Outline of Final Research Achievements

The performance of human visual functions degrades with age. For instance, the visual field becomes dark owing to a decrease of the amount of light received. Moreover, objects appear to be hazy by a decrease in the contrast sensitivity. Especially, the contrast sensitivity decreases remarkably as the spatial frequency increases. In this study, we proposed an image enhancement method which consists of a lightness conversion taking account of visual characteristics of elderly persons and an amplification of high spatial frequency components. Concretely, the lightness conversion was conducted within the color gamut by using a tone mapping. In addition, a sharpening based on the inverse characteristic function of the sensitivity decay curve was applied. The effectiveness of the proposed method is verified by experiments using several digital images.

Free Research Field

画像処理，信号処理

Academic Significance and Societal Importance of the Research Achievements

画像・映像処理の分野では古くから様々な方法が研究されているが，加齢による視覚特性変化を考慮した画像・映像強調手法に関する研究はあまり例がなく，本研究の実施は学術的に意義深い．また，全世代総ディジタル化社会においてディジタル表示デバイスの利便性（明視性，視認性）を向上させることは，人類のQuality of Lifeを直接的に向上させることになる．そのため，本研究の社会的な意義は大きい．