Generic Screen Than Specific Personnel Information Extraction Software Design And Realization

This thesis mainly introduced the related research technology and the realization method of the screen capture and enquiry system. The system described in this thesis is a software that running in the background and used to enquiry the information on the screen from the specific person information database.This software obtains text information on the screen of the computer at the office through screen capture, and then identification numbers is extracted, and used to compare with the text of national specific person information. It would alarm if a specific person was found. Because the software obtains information through screen capture, it doesn't establish direct connection to any of office-softwares in logic, so it could be used in the camputer system of all the rass-roots organization in our country.Screen capture is the core function of the software. The screen capture function is accomplished by using API hook. PE file structure, dynamic link library and hook technology of Windows System that used to API hook are described detailedly in this thesis. The concept and the principle of API hook, serveral kinds of dll injection method and API function redirection method are also introduced in the thesis. On this basis, the method of screen capture through API Hook is presented. And C++ code used to screen capture is listed.There are about 3 hundred thousand records of the national specific person information database for queries. Due to the amount of data and the speed, database has not been used. The identification numbers of the specific person information database were organized and sorted, and then these numbers are used for queries in memory.Because the user of the software is oriented to be establishment of all the rass-roots organization in our country, the method of automatic data update by network technology is used. Considering the situation with out network, the method of manual date update is provided.The thesis also introduced other key modules, such as data import, data filtering, information inquiry, and so on.