减少for循环的次数

reduce number of for loop

本文关键字:循环 for 减少      更新时间:2023-10-16

我写了一个检测行人的代码。代码完全可以工作,但是正如您在下面的代码中看到的,有许多for循环。我的问题是如何在不影响输出的情况下减少for循环的数量。

#include <opencv2/core/core.hpp> 
#include <opencv2/highgui/highgui.hpp> 
#include <opencv2/imgproc/imgproc.hpp> 
#include <opencv2/features2d/features2d.hpp>
#include <opencv2/objdetect/objdetect.hpp>
#include <iostream>
#include <stdio.h>
using namespace std;
using namespace cv;
void detectAndDisplay( Mat frame );
/** Global variables */
CascadeClassifier pedestrians_cascade;
Mat image1,image2,image3,image4,image5,image6,image7,image8,image9,image10;
Mat ped1,ped2,ped3,ped4,ped5,ped6,ped7,ped8,ped9,ped10;
int x;
int y;
int width, height;
int main( )
{
    // Load Face cascade (.xml file)
    pedestrians_cascade = CascadeClassifier("hogcascade_pedestrians.xml");
    // Read an images
    image1 = imread("ped1.jpg");
    image2 = imread("ped2.jpg");
    image3 = imread("ped3.jpg");
    image4 = imread("ped4.jpg");
    image5 = imread("ped5.jpg");
    image6 = imread("ped6.jpg");
    image7 = imread("ped7.jpg");
    image8 = imread("ped8.jpg");
    image9 = imread("ped9.jpg");
    image10 = imread("ped10.jpg");
     // these functions use to draw rectangles
    std::vector<Rect> ped1;
    pedestrians_cascade.detectMultiScale( image1, ped1, 1.1, , 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped1.size(); i++) // Iterate through all current elements (detected ped)
    {
       Point pt1(ped1[i].x, ped1[i].y); // Display detected ped on main window - live stream from camera
       Point pt2((ped1[i].x + ped1[i].width), (ped1[i].y + ped1[i].height));
        //rectangle(image1, ped1[i], Scalar(255, 0 , 0), 2, 8, 0);
        rectangle(image1,pt2,pt1, Scalar(255,0,0), 2,8,0);
    }
    std::vector<Rect> ped2;
    pedestrians_cascade.detectMultiScale( image2, ped2, 1.1, 5, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped2.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped2[i].x, ped2[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped2[i].x + ped2[i].width), (ped2[i].y + ped2[i].height));
        rectangle(image2, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped3;
    pedestrians_cascade.detectMultiScale( image3, ped3, 1.1, 2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped3.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped3[i].x, ped3[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped3[i].x + ped3[i].width), (ped3[i].y + ped3[i].height));
        rectangle(image3, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped4;
    pedestrians_cascade.detectMultiScale( image4, ped4, 1.1, 2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped4.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped4[i].x, ped4[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped4[i].x + ped4[i].width), (ped4[i].y + ped4[i].height));
        rectangle(image4, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped5;
    pedestrians_cascade.detectMultiScale( image5, ped5, 1.1, 2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped5.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped5[i].x, ped5[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped5[i].x + ped5[i].width), (ped5[i].y + ped5[i].height));
        rectangle(image5, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped6;
    pedestrians_cascade.detectMultiScale( image6, ped6, 1.1, 2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped6.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped6[i].x, ped6[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped6[i].x + ped6[i].width), (ped6[i].y + ped6[i].height));
        rectangle(image6, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped7;
    pedestrians_cascade.detectMultiScale( image7, ped7, 1.1, 2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped7.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped7[i].x, ped7[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped7[i].x + ped7[i].width), (ped7[i].y + ped7[i].height));
        rectangle(image7, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped8;
    pedestrians_cascade.detectMultiScale( image8, ped8, 1.1, 20, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped8.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped8[i].x, ped8[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped8[i].x + ped8[i].width), (ped8[i].y + ped8[i].height));
        rectangle(image8, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped9;
    pedestrians_cascade.detectMultiScale( image9, ped9, 1.1, 2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped9.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped9[i].x, ped9[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped9[i].x + ped9[i].width), (ped9[i].y + ped9[i].height));
        rectangle(image9, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    std::vector<Rect> ped10;
    pedestrians_cascade.detectMultiScale( image10, ped10, 1.1, 2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) );
    for (int i = 0; i < ped10.size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(ped10[i].x, ped10[i].y); // Display detected ped on main window - live stream from camera
        Point pt2((ped10[i].x + ped10[i].width), (ped10[i].y + ped10[i].height));
        rectangle(image10, pt2, pt1, Scalar(255, 0 , 0), 2, 8, 0);
    }
    imshow( "ped1", image1);
    /*imshow( "ped2", image2);
    imshow( "ped3", image3);
    imshow( "ped4", image4);
    imshow( "ped5", image5);
    imshow( "ped6", image6);
    imshow( "ped7", image7);
    imshow( "ped8", image8);
    imshow( "ped9", image9);
    imshow( "ped10", image10);*/
    waitKey(0);                   
    return 0;
}

为图像和ped变量创建外部std::vector:

std::vector<Mat> images(10);
std::vector<vector<Rect> > peds;
// ...
for (unsigned int p = 0; p < 10; ++p)
{
    pedestrians_cascade.detectMultiScale( images[p], peds[p],
                                         1.1, 5,
                                         0|CASCADE_SCALE_IMAGE,
                                         Size(30, 30) );
    for (int i = 0; i < peds[p].size(); i++) // Iterate through all current elements (detected ped)
    {
        Point pt1(peds[p][i].x, peds[p][i].y); // Display detected ped on main window - live stream from camera
        Point pt2((peds[p][i].x + peds[p][i].width),
                  (peds[p][i].y + peds[p][i].height));
        rectangle(images[p],
                  pt2, pt1,
                  Scalar(255, 0 , 0), 2, 8, 0);
    }
}