c++ - gpu::morphologyEx在CPU中比morphologyEx慢？

我正在编写一个c++代码，用于比较使用CPU和GPU版本的opencv的morphologyEx方法的性能。这是我的代码:

#include <opencv2/opencv.hpp>
#include <opencv2/gpu/gpu.hpp>
#include <sys/time.h>
#include <ctime>
using namespace cv;
using namespace std;


double start_timer()
{
     double start_time = (double) getTickCount();
     return start_time;
}

double end_timer(double start_time,int num_tests)
{
    double time = (1000 * ((double) getTickCount() - start_time)/ getTickFrequency());
    cout << "Average time of " << num_tests  << " frames is: " << time/num_tests <<  " ms" << endl;
    return time;
}


int main()
{
    Mat cpuSrc;
    cv::gpu::GpuMat src_gpu, dst_gpu;
    Mat dst;
    Mat element;
    int element_shape = MORPH_RECT;
    element = getStructuringElement(element_shape, Size(10, 10 ), Point(-1, -1) );
    cpuSrc = imread("images.jpeg",CV_LOAD_IMAGE_ANYDEPTH);

    if (!cpuSrc.data)
    {
        cerr << "Cannot read the data" << endl;
        return -1;
    }


    cout << "Starting calculating time for CPU ....." << endl;
    double start_time = start_timer();
    int d = 0;
    while(d<100)
    {
        cv::morphologyEx(cpuSrc, dst, CV_MOP_OPEN, element,Point(-1,-1),1);
    }

    double total_time_cpu = end_timer(start_time,d);



//--------------------------------------------------------------
    cout << "Starting calculating time for GPU ....." << endl;
    d = 0;
    cv::gpu::GpuMat buf1, buf2;
    gpu::Stream stream;
    double start_time_1 = start_timer();

    while(d<100)
    {
        stream.enqueueUpload(cpuSrc, src_gpu);
        cv::gpu::morphologyEx(src_gpu,dst_gpu,CV_MOP_OPEN,element,
                   buf1,buf2,Point(-1,-1),1,stream);
        stream.enqueueDownload(dst_gpu, dst);

    }
    stream.waitForCompletion();
    double total_time_gpu = end_timer(start_time_1,d);

    cout << "Gain is: " << total_time_cpu / total_time_gpu << endl;
    return 0;
}

该模拟的时间结果如下:



提前非常感谢您。

最佳答案

在初始化中，您应该调用:

cv::gpu::setDevice(0);

它将加速初始化。

关于c++ - gpu::morphologyEx在CPU中比morphologyEx慢？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/21054874/