imload_benchmark.cpp

#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>

#include <iostream>
#include <chrono>
#include <algorithm>
#include <vector>

#include "assert.h"
#include "dirent.h"

int main( int argc, char** argv )
{
    const char * path = "2010_03_09_drive_0023/2010_03_09_drive_0023_Images";
    std::vector<std::string> leftIm;
    std::vector<std::string> rightIm;
    
    DIR *dir;
    struct dirent *ent;
    
    if ((dir = opendir (path)) == NULL)
        return -1;

    while ((ent = readdir (dir)) != NULL)
    {
        std::string entry = ent->d_name;
        if (entry[1] == '1')
            leftIm.push_back(entry);
        else if(entry[1] == '2')
            rightIm.push_back(entry);
    }
    std::sort(leftIm.begin(), leftIm.end());
    std::sort(rightIm.begin(), rightIm.end());
    assert(leftIm.size() == rightIm.size());

    cv::Mat im1;
    cv::Mat im2;
    
    auto clock_start = std::chrono::system_clock::now();
    for(int i=0; i < leftIm.size(); i++)
    {
        im1 = imread((std::string) path + "/" + leftIm[i], cv::IMREAD_GRAYSCALE);
        im2 = imread((std::string) path + "/" + rightIm[i], cv::IMREAD_GRAYSCALE);
    }
    auto clock_end = std::chrono::system_clock::now();
    unsigned int elapsed_time = std::chrono::duration_cast<std::chrono::milliseconds>(clock_end-clock_start).count();
    std::cout << "reading all those images from disk took " << elapsed_time << " ms" << std::endl;
    float fps = ((float) leftIm.size() / (float) elapsed_time) * 1000;
    std::cout << "at " << fps << " fps" << std::endl;

}