Human-assisted OCR of Japanese books with different kinds of microtasks

Human-assisted OCR is a common approach for transcribing books and been used for many digital library projects. paper reports our project for transcribing the book collections of National Diet Library in this approach. project is unique in two ways. First, try to extend the human-assisted OCR approach by distributing microtasks in many ways other than just showing tasks in the specific Web page on PC screens. , we deal with Japanese books which have thousands of characters, of which look similar to each other. paper shows that we can expect high-quality results even if we transcribe Japanese texts with microtasks the number of preformed microtasks to be stable if we distribute microtasks to equipment with witch worker perform microtasks in their daily lives.