来个高手解释下这是什么意思 谢谢

memset(&m_com,0,sizeof(COMPVARS));
m_com.cbSize=sizeof(m_com);
m_com.dwFlags=ICMF_COMPVARS_VALID;
m_com.fccHandler=mmioFOURCC('x','v','i','d');
m_com.fccType=ICTYPE_VIDEO;
m_com.lFrame=0;
m_com.lKey=15;
m_com.lKeyCount=0;
m_com.lDataRate=780;
m_com.lpbiOut=(BITMAPINFO*)&m_outinfo;
m_com.hic=ICOpen(ICTYPE_VIDEO,mmioFOURCC('x','v','i','d'),ICMODE_COMPRESS);
m_com.cbState=1180;
ICCompressGetFormat(m_com.hic,&m_ininfo.bmiHeader,&m_outinfo.bmiHeader);
int ret=ICCompressBegin(m_com.hic,(BITMAPINFO*)&m_ininfo,(BITMAPINFO*)&m_outinfo);
if(ret!=ICERR_OK)
MessageBox("压缩失败");