警告 1 warning C4996: ‘fopen’: This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details. d:\opencv\2.4.9\opencv\build\include\opencv2\flann\logger.h 66 1 OpenCV
解决方法
_CRT_SECURE_NO_WARNINGS
打开“项目”→“属性”→“配置属性”→“C\C++”→“预处理器”→“预处理器定义”
然后将上面的这串字母复制到里面就可以了