Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) is a test used on web sources to differentiate between humans and automated computer robots. CAPTCHA on smartphone platforms is fraught with difficulty for users with visual and hearing impairment. For deaf users, speech as a CAPTCHA input method is not useable in noisy environments. For blind users, typing a letter requires to search for its button on the virtual keyboard; thus, it is time-consuming. Gesture input is therefore a solution for smartphone applications, as neither vision nor hearing is required. This research developed new CAPTCHAs, HearAct and SeeAct, which are suitable for blind, deaf, and sighted users. These CAPTCHAs provide two ways of presenting universally accessible challenges: (1) Users see an image, identify an object in the image and then identify a word that corresponds with that object (SeeAct); (2) users listen to an object’s sound (the “sound-maker”, e.g., a dog) and identify the sound-maker (HearAct). HearAct and SeeAct CAPTCHAs provide both audio and an image of the sound maker, simultaneously. In both, users analyze a word to determine whether the word has a stated letter and then use gestures to answer. If the identified word has the letter, the user must tap; if not, they must swipe. Considering usability and accessibility, as compared to most common audio CAPTCHAs (used by blind users) and text CAPTCHAs (used by deaf and sighted users), results indicate significantly improved accessibility using both HearAct and SeeAct CAPTCHAs. Gesture-based HearAct and SeeAct CAPTCHA have a higher success rate, are more accessible, require less solving time, and are preferred by all users over the traditional CAPTCHA method.

告诉计算机与人类完全分开的全自动公共图灵测试（CAPTCHA）是一种用于Web来源的测试，用于区分人类和自动计算机机器人。对于视力和听力障碍的用户，智能手机平台上的CAPTCHA充满困难。对于聋哑用户，在嘈杂的环境中不能使用语音作为CAPTCHA输入法。对于盲人用户，键入字母要求在虚拟键盘上搜索其按钮；因此，这很耗时。因此，手势输入是智能手机应用程序的解决方案，因为不需要视觉和听觉。这项研究开发了新的CAPTCHA，HearAct和SeeAct，适用于盲人，聋人和有视力的用户。这些验证码提供了两种提出普遍可访问挑战的方式：（1）用户看到图像，识别图像中的对象，然后识别与该对象相对应的单词（SeeAct）；（2）用户聆听对象的声音（例如狗的“发声者”）并识别发声者（HearAct）。HearAct和SeeAct CAPTCHA同时提供音频和发声器的图像。在这两种方法中，用户都会分析一个单词以确定该单词是否具有明确的字母，然后使用手势来回答。如果识别出的单词带有字母，则用户必须点击；如果没有，则必须滑动。与大多数常见的音频CAPTCHA（由盲人用户使用）和文本CAPTCHA（由聋哑人和有视力的用户使用）相比，考虑到可用性和可访问性，结果表明使用HearAct和SeeAct CAPTCHA可以显着改善可访问性。基于手势的HearAct和SeeAct CAPTCHA具有较高的成功率，更易于访问，