Keyword search in a cluttered environment is difficult in general, and even more challenging for people with low vision. While magnification can help in reading for low vision people, it does not facilitate efficient visual search due to the constriction of the field of view. The motivating observation for this study is that, in a large number of visual search tasks, people know what are they looking for (i.e., they know the keywords), they just do not know where to find them in the scene. We have developed a mobile application that allows the users to input keywords (by voice or by typing), uses an optical character recognition (OCR) engine to search for the provided keyword in the scene captured by the smartphone camera, and zooms in on the instances of the keyword detected in the captured images, to facilitate efficient information acquisition. In this paper we describe the development and evaluation of various aspects of the application, including comparing the various mainstream OCR engines that power the app, and an evaluation study comparing the app to the conventional optical magnifier vision aid. Normally sighted adults, while wearing blur glasses to lower their visual acuity, performed keyword searches for a series of items ranging from easy to difficult with the app and with a handheld magnifier. While there was no difference in the search times between the two methods for the easier tasks, the app was significantly faster than the magnifier for the difficult tasks.

中文翻译：

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用于现实世界场景中关键字搜索的移动应用程序

在杂乱的环境中搜索关键字通常很困难，对于低视力的人来说更具挑战性。虽然放大可以帮助低视力人群阅读，但由于视野的狭窄，它不利于有效的视觉搜索。这项研究的动机观察是，在大量的视觉搜索任务中，人们知道他们在寻找什么（即他们知道关键词），他们只是不知道在场景中的哪里找到它们。我们开发了一个移动应用程序，允许用户输入关键字（通过语音或打字），使用光学字符识别 (OCR) 引擎在智能手机相机拍摄的场景中搜索提供的关键字，并放大在捕获的图像中检测到关键字的实例，以促进有效的信息获取。在本文中，我们描述了应用程序各个方面的开发和评估，包括比较为应用程序提供动力的各种主流 OCR 引擎，以及将应用程序与传统光学放大镜助视器进行比较的评估研究。视力正常的成年人在戴着模糊眼镜以降低视力时，使用应用程序和手持放大镜对一系列从易到难的项目进行关键字搜索。虽然对于较简单的任务，这两种方法之间的搜索时间没有差异，但对于较难的任务，该应用程序的搜索速度明显快于放大镜。以及将该应用程序与传统光学放大镜助视器进行比较的评估研究。视力正常的成年人在戴着模糊眼镜以降低视力时，使用应用程序和手持放大镜对一系列从易到难的项目进行关键字搜索。虽然对于较简单的任务，这两种方法之间的搜索时间没有差异，但对于较难的任务，该应用程序的搜索速度明显快于放大镜。以及将该应用程序与传统光学放大镜助视器进行比较的评估研究。视力正常的成年人在戴着模糊眼镜以降低视力时，使用应用程序和手持放大镜对一系列从易到难的项目进行关键字搜索。虽然对于较简单的任务，这两种方法之间的搜索时间没有差异，但对于较难的任务，该应用程序的搜索速度明显快于放大镜。