CascadeClassifier openCV

Question

我用C++编写了这个程序，使用OpenCV来检测我拥有的pedestrians.xml文件。程序应读取所有输入图像，并在行人所在的输出图像上显示蓝色矩形。但是代码给了我错误。有没有人能告诉我为什么会出现这些错误？

#include <opencv2/core/core.hpp> 
#include <opencv2/highgui/highgui.hpp> 
#include <opencv2/imgproc/imgproc.hpp> 
#include <opencv2/features2d/features2d.hpp> 
#include<iostream> 
#include <stdio.h> 
#include <string> 
#include <vector> 

using namespace std; 
using namespace cv; 

void detectAndDisplay(Mat frame); 

/** Global variables */ 
String pedestrians_name = "hogcascade_pedestrians.xml"; 
//CascadeClassifier pedestrians; 
string window_name = "Capture - pedestrians detection"; 
RNG rng(12345); 

/** @function main */ 
int main(int argc, const char** argv) 
{ 
    CvCapture* capture; 
    Mat frame; 

    //-- 1. Load the cascades 
    //if(!pedestrians.load(pedestrians_name)){ printf("--(!)Error loading\n"); return -1; }; 
    Mat image = imread("ped1.jpg"); 
    Mat image_keypoints; 
    cvtColor(image, image_keypoints, CV_BGR2GRAY); 

    return 0; 
} 

/** @function detectAndDisplay */ 
void detectAndDisplay(Mat frame) 
{ 
    std::vector<Rect> pedestrians; 
    Mat frame_gray; 

    cvtColor(frame, frame_gray, CV_BGR2GRAY); 
    equalizeHist(frame_gray, frame_gray); 

    //-- Detect faces 
    pedestrians.detectMultiScale(frame_gray, pedestrians, 1.1, 2, 0|CV_HAAR_SCALE_IMAGE, Size(30, 30)); 
    void CascadeClassifier::detectMultiScale(const Mat& image, vector<Rect>& objects, double scaleFactor=1.1, int minNeighbors=3, int flags=0, Size minSize=Size(), Size maxSize=Size()); 

    for(int i = 0; i < pedestrians.size(); i++) 
    { 
    Point center(pedestrians[i].x + pedestrians[i].width*0.5, pedestrians[i].y + pedestrians[i].height*0.5); 
    ellipse(frame, center, Size(pedestrians[i].width*0.5, pedestrians[i].height*0.5), 0, 0, 360, Scalar(255, 0, 255), 4, 8, 0); 

    Mat faceROI = frame_gray(pedestrians[i]); 
    std::vector<Rect> eyes; 

    //-- In each face, detect eyes 
    /*eyes_cascade.detectMultiScale(faceROI, eyes, 1.1, 2, 0 |CV_HAAR_SCALE_IMAGE, Size(30, 30)); 

    for(size_t j = 0; j < eyes.size(); j++) 
    { 
     Point center(faces[i].x + eyes[j].x + eyes[j].width*0.5, faces[i].y + eyes[j].y + eyes[j].height*0.5); 
     int radius = cvRound((eyes[j].width + eyes[j].height)*0.25); 
     circle(frame, center, radius, Scalar(255, 0, 0), 4, 8, 0); 
    }*/ 
    } 
    //-- Show what you got 
    imshow(window_name, frame); 
} 

这些都是错误的：

cascade.cpp: In function âvoid detectAndDisplay(cv::Mat)â: 
cascade.cpp:46: error: âclass std::vector<cv::Rect_<int>, std::allocator<cv::Rect_<int> > >â has no member named âdetectMultiScaleâ 
cascade.cpp:46: error: âCV_HAAR_SCALE_IMAGEâ was not declared in this scope 
cascade.cpp:47: error: âCascadeClassifierâ has not been declared 
cascade.cpp:47: error: invalid use of qualified-name â<declaration error>::detectMultiScaleâ 

Answer 1

您需要添加opencv_objdetect库。并包含“opencv2/objdetect.hpp”。

Answer 2

创建级联分类对象，并加载XML文件obj.load（XML文件路径）

Answer 3

首先，在main（）你从来没有所谓的detectAndDisplay（）吧？如果要执行它，则需要调用它...

其次，您需要在使用detectMultiScale之前在detectAndDisplay（）中声明并加载级联分类器。

CascadeClassifier pedestrians; 
if(!pedestrians.load(pedestrians_name)){ 
printf("--(!)Error loading\n"); 
return;} 
//..... 
pedestrians.detectMultiScale(frame_gray, pedestrians, 1.1, 2, 0|CV_HAAR_SCALE_IMAGE, Size(30, 30));