@article{oai:miyazaki-u.repo.nii.ac.jp:00006346,
 author = {臼崎, 翔太郎 and Usuzaki, Shotaro and 臼﨑, 翔太郎 and 砂本, 佑紀 and Okazaki, Naonobu and 岡崎, 直宣 and Yamaba, Hisaaki and 山場, 久昭 and Aburada, Kentaro and 油田, 健太郎 and 臼崎, 翔太郎 and Usuzaki, Shotaro and 臼﨑, 翔太郎 and Sunamoto, Yuki},
 journal = {宮崎大学工学部紀要, Memoirs of Faculty of Engineering, University of Miyazaki},
 month = {Sep},
 note = {CAPTCHA is now widely used to prevent the bot from sending unauthorized service requests. CAPTCHA is a system that imposes tasks that are easy for humans and difficult for machines and thereby detect access from the bot. Unfortunately, many researchers have already reported that bots can break current CAPTCHAs by OCR and machine learning technology. Therefore, it is necessary to add interference for machine resistance. However, such interference also has a negative effect on human perception. Therefore, we adopt a color constancy to CAPTCHA. The color constancy is a human visual characteristic and is known to be difficult to reproduce mathematically. However, this CAPTCHA has a problem that human success is low and machine success rate is high. To solve this issue, we proposed an improved CAPTCHA by processing the base image and creating a new color interference filter. The first contrivance is to leave only a specific object color in the base image for defending the attack by the Gray-World algorithm, which is vulnerable to color bias. The second contrivance solves the weakness that the color filter does not always work effectively. We evaluated the effect of these devices on the accuracy rate of humans and machines and usability.},
 pages = {251--255},
 title = {色の恒常性を利用したCAPTCHAのユーザビリティと機械攻撃耐性向上のための検討},
 volume = {49},
 year = {2020},
 yomi = {ウスザキ, ショウタロウ and オカザキ, ナオノブ and ヤマバ, ヒサアキ and アブラダ, ケンタロウ and ウスザキ, ショウタロウ}
}