The Design And Implementation Of The Common OCR Framework Based On Symbian OS

This paper introduces the design and implementation of the common OCR framework based on Symbian OS. As a popular operating system at present, Symbian OS is used widely and the Series 60 platform is the most popular platforms on the Symbian OS. Because of the portability and the shoot function of mobile, it is very necessary to design and implement OCR framework like this to satisfy different requirements. Firstly, this paper introduces some important knowledge about Symbian OS needed by developing this framework, including active object, client/server framework, ECom framework and so on. And then this paper introduces the design and implementation of the OCR client/server framework, analyzing the interface of OCR engine, the communication between the client and server, the definition of the message format, the internalization and the externalization of data. This paper then demonstrates how to develop plugins which are fit for different scenarios based on this framework, mainly concerning their specialties and their working ways. And then the paper introduces the development of plain text OCR plugin, analyzing the design and the implementation of the layout analysis function and the block analysis function. Finally, this paper introduces how to use plugin in the development of application, including the how to load the plugin instance and how to use the call back function supplied by the plugin to satisfy the different requirements of the application. By reading this paper, reader can learn how to design and implement a common OCR application framework, how to develop different plugins according to different scenarios based on this framework and how to use plugin to develop different applications which are satisfy the different scenarios.