了解OpenCV中OpenCL的用法(材质/单元对象）

我运行下面的代码来检查GPU和CPU使用情况之间的性能差异。我正在计算cv::cvtColor()函数的平均时间。我调用了四个函数：

1. Just_mat()(对于Mat对象不使用OpenCL)
2. Just_UMat()(对于Umat对象不使用OpenCL)
3. OpenCL_Mat()(对Mat对象使用OpenCL)
4. OpenCL_UMat()(对UMat对象使用OpenCL)

用于CPU和GPU
我没有发现GPU和CPU使用之间存在巨大的性能差异。

int main(int argc, char* argv[])
{
loc = argv[1];
just_mat(loc);// Calling function Without OpenCL 
just_umat(loc);//Calling function Without OpenCL 
cv::ocl::Context context;
std::vector<cv::ocl::PlatformInfo> platforms;
cv::ocl::getPlatfomsInfo(platforms);
for (size_t i = 0; i < platforms.size(); i++)
{
//Access to Platform
const cv::ocl::PlatformInfo* platform = &platforms[i];
//Platform Name
std::cout << "Platform Name: " << platform->name().c_str() << "n" << endl;
//Access Device within Platform
cv::ocl::Device current_device;
for (int j = 0; j < platform->deviceNumber(); j++)
{
//Access Device
platform->getDevice(current_device, j);
int deviceType = current_device.type();
cout << "Device name:  " << current_device.name() << endl;
if (deviceType == 2)
cout << context.ndevices() << " CPU devices are detected." << std::endl;
if (deviceType == 4)
cout << context.ndevices() << " GPU devices are detected." << std::endl;
cout << "===============================================" << endl << endl;
switch (deviceType) 
{
case (1 << 1):
cout << "CPU devicen";
if (context.create(deviceType))
opencl_mat(loc);//With OpenCL Mat
break;
case (1 << 2):
cout << "GPU devicen";              
if (context.create(deviceType))
opencl_mat(loc);//With OpenCL UMat
break;
}
cin.ignore(1);
}
}
return 0;
}
int just_mat(string loc);// I check for the average time taken for cvtColor() without using OpenCl
int just_umat(string loc);// I check for the average time taken for cvtColor() without using OpenCl
int opencl_mat(string loc);//ocl::setUseOpenCL(true); and check for time difference for cvtColor function
int opencl_umat(string loc);//ocl::setUseOpenCL(true); and check for time difference for cvtColor function

上述代码的输出(以毫秒为单位)为
__________________________________________
|GPU名称|带OpenCL Mat |带OpenCL UMat |
| _________________________________________ |
|--Carrizo---|--------7.69052-------0.247069-----|
>|_________________________________________ |
|--Island---|--------71.124555-------0.233345-----|
|_________________________________________ |

_________________________________________
|----CPU---|带OpenCL Mat |带OpenCL UMat |
|1________________________________________ |
|----AMD---|---------6.76169-|---------0.231103-|
>|________________________________________ |

_______________________________________________
|----CPU---|WithOut OpenCL Mat|WithOut Open Cl UMat|
|1_______________________________________________ |
|----AMD---|-------7.15959------|--------------0.246138------|
>|_______________________________________________ |

在代码中，使用Mat对象总是在CPU&使用UMat对象始终在GPU上运行，与代码ocl::setUseOpenCL(true/false);无关
有人能解释所有输出时间变化的原因吗

还有一个问题，我没有将任何OpenCL特定的.dll与.exe文件一起使用，但GPU在使用Cmake构建OpenCV时没有任何错误，我检查了With_OpenCL，这是否在opencv_World310.dll中构建了所有OpenCL所需的功能？