linux+Qt+Opencv实现采集摄像头采集，截图，边缘检测，霍夫变换
最近在做⼀个机器视觉货物分拣系统，⼩⽩⼀个，从头开始学起。希望写博客可以督促⾃⼰加快步伐，完成任务！
系统：ubantu14.04
opencv版本 :3.0.0
Qt版本：5.7
程序功能：实现摄像头视频的采集，截图，边缘检测和霍夫直线检测。
运⾏效果：
原始截图
⽣成的灰度图
边缘检测和霍夫变换直线检测后的图像
⾸先你得先装好软件和库才⾏。⽹上教程很多，这个就不多说了。 话不多说，直接上程序：
1，新建⼀个qt wiget⼯程；
2，在.pro⽂件中最后加⼊opencv库⽂件
INCLUDEPATH += .
INCLUDEPATH += /usr/local/include
INCLUDEPATH += /usr/local/include/opencv
INCLUDEPATH += /usr/local/include/opencv2
INCLUDEPATH += /usr/local/include/opencv2/core
INCLUDEPATH += /usr/local/include/opencv2/highgui
INCLUDEPATH += /usr/local/include/opencv2/imgproc
INCLUDEPATH += /usr/local/include/opencv2/flann毛毛虫游戏
INCLUDEPATH += /usr/local/include/opencv2/photo
INCLUDEPATH += /usr/local/include/opencv2/video
INCLUDEPATH += /usr/local/include/opencv2/features2d
INCLUDEPATH += /usr/local/include/opencv2/objdetect
INCLUDEPATH += /usr/local/include/opencv2/calib3d
INCLUDEPATH += /usr/local/include/opencv2/ml
INCLUDEPATH += /usr/local/include/opencv2/contrib
LIBS += `pkg-config opencv --cflags --libs`
3，在头⽂件中写⼊如下代码：
其中private slots：下的函数是在Ui界⾯添加按钮的槽函数后⾃动⽣成的
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
#include <opencv2/opencv.hpp>
#include <iostream>
#include "highgui.h"
using namespace cv;
using namespace std;
namespace Ui {
class Widget;
}
class Widget : public QWidget
{
Q_OBJECT
public:
explicit Widget(QWidget *parent = 0);
~Widget();
private slots:
void on_Cut_clicked();
void on_Open_clicked();
void on_Quit_clicked();
private:
Ui::Widget *ui;
春节用英语怎么写Mat edges;
Mat mid_edges;
Mat frame;
Mat Gray_Frame;
Mat Canny_Frame;
QImage Img;日本留学申请
QImage Scaled_Img;
QImage Cut_Img;
QImage Gray_Img;
QImage Scaled_Gray_Img;
QImage Canny_Img;
QImage Scaled_Canny_Img;
vector<Vec2f> lines;//定义⼀个⽮量结构lines⽤于存放得到的线段⽮量集合
};
#endif // WIDGET_H
4，在widget.c⽂件下⾯加⼊以下代码：
#include "widget.h"
#include "ui_widget.h"
我学会了画画Widget::Widget(QWidget *parent) :
QWidget(parent),
ui(new Ui::Widget)
{
ui->tupUi(this);
止痛散}
我学会了什么作文400字
Widget::~Widget()
delete ui;
}
void Widget::on_Cut_clicked()
{
Cut_Img =Scaled_Img;
QLabel *Img_label =new QLabel(this);
Img_label->tGeometry(360,20,300,200);
Img_label->tPixmap(QPixmap::fromImage(Cut_Img));
Img_label->resize( Img_label->pixmap()->size());
Img_label->show();
cvtColor(frame,Gray_Frame,CV_BGR2GRAY);
//anny算⼦边缘检测
Canny(Gray_Frame,Canny_Frame,75,80,3);
//霍夫变换直线检测算法---8bit pic,tp,angel,length_limit
HoughLines(Canny_Frame, lines, 3, CV_PI/20, 70, 0, 0 );
//依次在图中绘制出每条线
for( size_t i = 0; i < lines.size(); i++ )
{
float rho = lines[i][0], theta = lines[i][1];
Point pt1, pt2;
double a = cos(theta), b = sin(theta);
double x0 = a*rho, y0 = b*rho;
pt1.x = cvRound(x0 + 10000*(-b));
pt1.y = cvRound(y0 + 10000*(a));
pt2.x = cvRound(x0 - 10000*(-b));
pt2.y = cvRound(y0 - 10000*(a));
line( Canny_Frame, pt1, pt2, Scalar(55,100,195), 1, CV_AA);
}
/*
//灰度图显⽰
肉中肉Gray_Img = QImage((const unsigned char*)(Gray_Frame.data), ls, ws, QImage::Format_Grayscale8);
Scaled_Gray_Img= Gray_Img.scaled(Gray_Img.width()/2,Gray_Img.height()/2,Qt::KeepAspectRatio) ;
QLabel *Gray_Img_label =new QLabel(this);
Gray_Img_label->tGeometry(20,260,300,200);
Gray_Img_label->tPixmap(QPixmap::fromImage(Scaled_Gray_Img));
Gray_Img_label->resize( Gray_Img_label->pixmap()->size());
Gray_Img_label->show();
*/
Canny_Img = QImage((const unsigned char*)(Canny_Frame.data), ls, ws, QImage::Format_Grayscale8); Scaled_Canny_Img= Canny_Img.scaled(Canny_Img.width()/2,Canny_Img.height()/2,Qt::KeepAspectRatio) ;
QLabel *Gray_Img_label =new QLabel(this);
Gray_Img_label->tGeometry(20,280,300,200);
Gray_Img_label->tPixmap(QPixmap::fromImage( Scaled_Canny_Img));
Gray_Img_label->resize( Gray_Img_label->pixmap()->size());
Gray_Img_label->show();
imwrite( "/home/zy/qt_pro/frame.jpg", frame );
imwrite( "/home/zy/qt_pro/Gray_Image.jpg", Gray_Frame );
imwrite( "/home/zy/qt_pro/Canny_Frame.jpg", Canny_Frame );
}
void Widget::on_Open_clicked()
{
VideoCapture cap(-1);
/
/设置视频格式
cap.t(CV_CAP_PROP_FRAME_WIDTH , 640);
团圆的诗句cap.t(CV_CAP_PROP_FRAME_HEIGHT , 480);
if(!cap.isOpened())
