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哈弗曼编码的课程设计报告

to become involved in document imaging, you presumably already have a large collection of paper documents. These documents must be converted into electronic images in a process known as backfile conversion. According to one particularly practical article, this process involves the following five steps:(12) 
Document PreparationOrganize and discard old documents. 
ScanningPurchase an appropriate scanner for your documents. Autofeed scanners are a myth; hands-on feeding is a reality. 
IndexingCreate all potential identifiers, using current technology such as autoindexing, OCR, and bar codes. Where possible, use existing databases to retrieve additional information, such as employee information from an ID. 
As part of the document conversion process, paper documents are scanned, and images are converted into electronic files and kept in large electronic filing cabinets.(13) The document images may be recognized by optical character recognition (OCR) software and converted into computer interpretable text, which can be indexed and searched. 
According to the news magazine Imaging World, "office workers spend 60% of the day dealing with paper documents and U.S. businesses continue to create over one billion pages of paper each day."(14) That is a lot of trees. The same article categorizes the imaging market into five components: 
1 image input 
2 image storage 
3 image management and processing 
4 image communications 
5 image output and display 
Let us examine three aspects of these components. First, the OCR part of the input component; second, text retrieval, part of the management and processing component; finally, the media issues that are part of the storage component.