下面是已有的makefile的部分代码
PREFIX = /usr/local INCLUDES = -I../UsageEnvironment/include -I../groupsock/include -I../liveMedia/include -I../BasicUsageEnvironment/include # Default library filename suffixes for each library that we link with. The "config.*" file might redefine these later. libliveMedia_LIB_SUFFIX = $(LIB_SUFFIX) libBasicUsageEnvironment_LIB_SUFFIX = $(LIB_SUFFIX) libUsageEnvironment_LIB_SUFFIX = $(LIB_SUFFIX) libgroupsock_LIB_SUFFIX = $(LIB_SUFFIX) ##### Change the following for your environment: COMPILE_OPTS = $(INCLUDES) -m64 -fPIC -I/usr/local/include -I. -O2 -DSOCKLEN_T=socklen_t -D_LARGEFILE_SOURCE=1 -D_FILE_OFFSET_BITS=64 MEDIA_SERVER = live555MediaServer$(EXE) ALL = $(MEDIA_SERVER) all: $(ALL) MEDIA_SERVER_OBJS = live555MediaServer.$(OBJ) DynamicRTSPServer.$(OBJ) live555MediaServer.$(CPP): DynamicRTSPServer.hh version.hh DynamicRTSPServer.$(CPP): DynamicRTSPServer.hh
USAGE_ENVIRONMENT_DIR = ../UsageEnvironment USAGE_ENVIRONMENT_LIB = $(USAGE_ENVIRONMENT_DIR)/libUsageEnvironment.$(libUsageEnvironment_LIB_SUFFIX) BASIC_USAGE_ENVIRONMENT_DIR = ../BasicUsageEnvironment BASIC_USAGE_ENVIRONMENT_LIB = $(BASIC_USAGE_ENVIRONMENT_DIR)/libBasicUsageEnvironment.$(libBasicUsageEnvironment_LIB_SUFFIX) LIVEMEDIA_DIR = ../liveMedia LIVEMEDIA_LIB = $(LIVEMEDIA_DIR)/libliveMedia.$(libliveMedia_LIB_SUFFIX) GROUPSOCK_DIR = ../groupsock GROUPSOCK_LIB = $(GROUPSOCK_DIR)/libgroupsock.$(libgroupsock_LIB_SUFFIX) LOCAL_LIBS = $(LIVEMEDIA_LIB) $(GROUPSOCK_LIB) $(BASIC_USAGE_ENVIRONMENT_LIB) $(USAGE_ENVIRONMENT_LIB) LIBS = $(LOCAL_LIBS) $(LIBS_FOR_CONSOLE_APPLICATION) live555MediaServer$(EXE): $(MEDIA_SERVER_OBJS) $(LOCAL_LIBS) $(LINK)$@ $(CONSOLE_LINK_OPTS) $(MEDIA_SERVER_OBJS) $(LIBS) #live555MediaServer$(EXE): $(MEDIA_SERVER_OBJS) $(LOCAL_LIBS) # c++ -o $@ -L. $(MEDIA_SERVER_OBJS) $(LIBS)
首先我们需要看main程序包含了哪些第三方头文件，打开main程序
可以看到包含了core.hpp imgproc.hpp highgui.hpp videoio.hpp 这四个opencv库的头文件，因此首先需要找到这些头文件的位置，将这些头文件位置写入到makefile中。
可以通过文件搜索来找到这些文件的位置
可以看到这些文件都在这个文件夹中，由于头文件中自带了这些文件的上级文件夹名，因此添加路径时也可以只包括到这个文件夹的上级文件夹名称，即opencv4即可
所以在INCLUDE后面添加 -I/usr/local/include/opencv4
头文件加进去之后，还要找到对应的库添加到makefile中，库的名称通常和头文件名称对应，如果不知道库的名称，可以通过名称搜索来寻找这些库的位置，比如core.hpp可以搜索core.a 或者 core.so，然后在搜索出来的结果中筛选出正确的库文件
这里的libopencv_core.so就是需要添加的库文件之一了。
进入到这个路径的文件夹中，可以看到这个文件夹中还包含有其他的头文件对应的库，因此是这个路径没错了
然后就需要在makefile中添加
OPENCV_DIR = -L/usr/local/lib
OPENCV_LIBS= $(OPENCV_DIR) -lopencv_core -lopencv_imgproc -lopencv_highgui -lopencv_videoio
OPENCV_LIBS 这个变量就是需要添加的库路径和库
然后再把这个库添加到编译规则中去
将LIBS中添加 $(OPENCV_LIBS) 这样在执行编译规则时，才能用上这些库，一定要添加到规则中，让规则找得到这些库才算添加成功
修改之后的makefile如下所示，修改过的部分用红色标记出
PREFIX = /usr/local INCLUDES = -I../UsageEnvironment/include -I../groupsock/include -I../liveMedia/include -I../BasicUsageEnvironment/include -I/usr/local/include/opencv4 # Default library filename suffixes for each library that we link with. The "config.*" file might redefine these later. libliveMedia_LIB_SUFFIX = $(LIB_SUFFIX) libBasicUsageEnvironment_LIB_SUFFIX = $(LIB_SUFFIX) libUsageEnvironment_LIB_SUFFIX = $(LIB_SUFFIX) libgroupsock_LIB_SUFFIX = $(LIB_SUFFIX) ##### Change the following for your environment: COMPILE_OPTS = $(INCLUDES) -m64 -fPIC -I/usr/local/include -I. -O2 -DSOCKLEN_T=socklen_t -D_LARGEFILE_SOURCE=1 -D_FILE_OFFSET_BITS=64 MEDIA_SERVER = live555MediaServer$(EXE) ALL = $(MEDIA_SERVER) all: $(ALL) MEDIA_SERVER_OBJS = live555MediaServer.$(OBJ) DynamicRTSPServer.$(OBJ) live555MediaServer.$(CPP): DynamicRTSPServer.hh version.hh DynamicRTSPServer.$(CPP): DynamicRTSPServer.hh USAGE_ENVIRONMENT_DIR = ../UsageEnvironment USAGE_ENVIRONMENT_LIB = $(USAGE_ENVIRONMENT_DIR)/libUsageEnvironment.$(libUsageEnvironment_LIB_SUFFIX) BASIC_USAGE_ENVIRONMENT_DIR = ../BasicUsageEnvironment BASIC_USAGE_ENVIRONMENT_LIB = $(BASIC_USAGE_ENVIRONMENT_DIR)/libBasicUsageEnvironment.$(libBasicUsageEnvironment_LIB_SUFFIX) LIVEMEDIA_DIR = ../liveMedia LIVEMEDIA_LIB = $(LIVEMEDIA_DIR)/libliveMedia.$(libliveMedia_LIB_SUFFIX) GROUPSOCK_DIR = ../groupsock GROUPSOCK_LIB = $(GROUPSOCK_DIR)/libgroupsock.$(libgroupsock_LIB_SUFFIX) OPENCV_DIR = -L/usr/local/lib OPENCV_LIBS= $(OPENCV_DIR) -lopencv_core -lopencv_imgproc -lopencv_highgui -lopencv_videoio LOCAL_LIBS = $(LIVEMEDIA_LIB) $(GROUPSOCK_LIB) $(BASIC_USAGE_ENVIRONMENT_LIB) $(USAGE_ENVIRONMENT_LIB) LIBS = $(LOCAL_LIBS) $(OPENCV_LIBS) $(LIBS_FOR_CONSOLE_APPLICATION) live555MediaServer$(EXE): $(MEDIA_SERVER_OBJS) $(LOCAL_LIBS) $(LINK)$@ $(CONSOLE_LINK_OPTS) $(MEDIA_SERVER_OBJS) $(LIBS) #live555MediaServer$(EXE): $(MEDIA_SERVER_OBJS) $(LOCAL_LIBS) # c++ -o $@ -L. $(MEDIA_SERVER_OBJS) $(LIBS)
添加完成之后，在执行make，就可以看到不再提示错误
或者提示找不到函数的错误
会正常完成编译。