安装opencv时，Downloadingippicv_linux_20151201.tgz...之后报错，原因是下载本文件时超时。解决办法：1.将本文件copy到，和opencv3.1同一级目录下。如：dir/opencv-3.1.0dir/ippicv_linux_20151201.tgz2.执行下面命令ipp_file=../ippicv_linux_20151201.tgz&&ipp_hash=$(md5sum$ipp_file|cut-d""-f1)&&ipp_dir=3rdparty/ippicv/downloads/linux-$ip