摘 要
視頻聊天系統(tǒng)作為一種新型的通信和交流工具，突破了地域的限制，可以提供更為便捷、靈活、全面的音、視頻信息的傳遞和服務，具有極其廣泛的發(fā)展前景。
本文介紹了采用Microsoft Visual C++ 6.0編程開發(fā)視頻聊天系統(tǒng)的一套比較常用的解決方案。文字聊天采用TCP模式；語音視頻聊天采用UDP模式，在客戶端之間點對點的進行。在該方案中，通過函數(shù)庫VFW來實現(xiàn)視頻捕獲、影像壓縮以及影像播放。微軟公司提供的專門用于視頻捕獲開發(fā)的工具包VFW，為在Windows操作系統(tǒng)中實現(xiàn)視頻捕獲提供了標準的接口，從而大大降低了程序的開發(fā)難度。在視頻傳輸方面，則通過組建視頻幀，將位圖形式的視頻幀壓縮成幀格式的Mpeg4流，傳輸?shù)娇蛻舳撕螅鈮翰@示影像。同時，在本方案中，采用了線程來實現(xiàn)語音錄制和語音回放，最終實現(xiàn)了通過服務器中轉的文字聊天、點對點的語音視頻聊天。
關鍵詞：文字聊天；VFW；視頻捕獲；視頻傳輸；語音錄制；語音回放
The Design and Realization of LAN-Based Video Chat Room System
Abstract
As a new tool about communication, video chatting system has broken through geographical restrictions, has provides more convenient, flexible and complete transmission and service. Furthermore, it has a very bright future.
The common solution about how to develop a video chatting system is introduced by the Microsoft Visual C + + 6.0 programming. TCP model is used in the text chatting and UDP for the point-to-point video chats between the Clients. In this plan, Video Capture, Video Compression Manager and DrawDib are realized by the functions of VFW Library. The special kit VFW (Video for Windows) in video capture offered by Microsoft Corporation, has provided a standard interface for video capture in Windows Operating System and thus greatly reduced the hardship of programming. In video transmission aspect, it requires a video frame which is compressed the video frame of bitmap into Mpeg4 steam of frame form. Then it will be decompressed into images since it has been arrived the Client. Meanwhile, the thread is used to achieve audio recording and replaying. Finally, it has realized the text chatting through a server to transit, the point-to-point audio and video chats.
Key words: text chatting; VFW; Video Capture; video transmission; audio recording; audio playing
