基于MSH263编码器协同系统的设计与实现

Research and implementation of a MSH263 codec based collaborative system

使用代理动态链接库对Windows(R)Net Meeting(R)调用MSH263编码的过程进行了记录。通过与标准调用序列的对比,发现了未公开的两个ICM消息和一组状态数据,使得MSH263编码器可以在用户程序中应用。给出了MSH263编码帧中隐含的RTP切分索引数据格式,并由此提出了快速切分算法。基于以上方法构造的实时多媒体协同系统,可以与AccessGrid及H.323系统良好互通,已成功应用于多项国家级项目。

Created a proxy dynamic link library to record call sequence of Windows(R) NetMeeting(R) on MSH263 codec. By compared with standard sequence, two undocumented ICM messages and a state block was opened out, which made using MSH263 in user application possible. The format of RTP fragmenting hint which is hidden in compressed picture was supposed. A quick division arithmetic was developed on that. The real-time multimedia collaborative system based on techniques mentioned above can cooperate with AccessGrid an...