摄像头调用出错，请教

reapercc

报错内容如下：
chris@chris-TM1701:~/opencv/VideoCapture/build$ make
Scanning dependencies of target Videocapture
[ 50%] Building CXX object CMakeFiles/Videocapture.dir/Videocapture.cpp.o
[100%] Linking CXX executable Videocapture
/usr/lib/gcc/x86_64-linux-gnu/7/../../../x86_64-linux-gnu/Scrt1.o：在函数‘_start’中：
(.text+0x20)：对‘main’未定义的引用
collect2: error: ld returned 1 exit status
CMakeFiles/Videocapture.dir/build.make:135: recipe for target 'Videocapture' failed
make[2]: *** [Videocapture] Error 1
CMakeFiles/Makefile2:67: recipe for target 'CMakeFiles/Videocapture.dir/all' failed
make[1]: *** [CMakeFiles/Videocapture.dir/all] Error 2
Makefile:83: recipe for target 'all' failed
make: *** [all] Error 2


萌新求解，，

代码
#include<iostream>
#include<opencv2/opencv.hpp>
#include<opencv2/highgui/highgui.hpp>
#include<opencv2/imgproc/imgproc.hpp>
using namespace std;
using namespace cv;
int mian()
{
    VideoCapture capture(0);
    while(true)
    {
        Mat frame;
        capture>>frame;
        imshow("Video",frame);
        waitKey(30);
    }
    return 0;
}



CMakeLists.txt 文件
cmake_minimum_required( VERSION 2.8 )
project( Videocapture )
#set( CMAKE_CXX_FLAGS "-std=c++11" )
find_package( OpenCV 3 REQUIRED )
include_directories( ${OpenCV_INCLUDE_DIRS} )
add_executable( Videocapture Videocapture.cpp)
target_link_libraries( Videocapture ${OpenCV_LIBS})

lans625

VideoCapture capture(0);
这个改成
VideoCapture capture(-1);
或
VideoCapture capture(1);
试试..

或者看看这个demo,看看别人是怎么调用的
http://www.opencv.org.cn/opencvd ... #cascade-classifier

mobonihao

int mian()