获取从1970年到现在的时间的毫秒数,用于记录视频帧实时时间
long long CSVGetLocalTime()
{
struct timeval time;
struct timezone tz;
gettimeofday(&time, &tz);
printf("time is %lld\n", time.tv_sec*1000 + time.tv_usec/1000);
return time.tv_sec*1000 + time.tv_usec/1000;
}