How to include and use OpenCv3.1.0 library to CUDA file(.cu)?

Question

I tried to implement my own kernel to median filter like this pseudo code:

//main.cpp
#include "opencv2/opencv.hpp"
cv::Mat inputMat = cv::imread()
cudaMedianCaller (inputMat, kernelMat)

//medianFilter.h
#include "opencv2/opencv.hpp"
cudaMedianCaller (const cv::Mat& inputMat, cv::Mat& kernelMat);

//medianFilter.cu
cudaMedianCaller (const cv::Mat& inputMat, cv::Mat& kernelMat)
{
    kernelMedianFilter<<< , >>> (uchar3* d_inputMat, uchar* d_kernelMat)
}

__global__ void kernelMedianFilter (uchar3* d_inputMat, uchar* d_kernelMat)
{

}

I get compile error :

C1083: cannot open include file:'opencv2/opencv.hpp' : No such file or directory

I know that .cu file compile with nvcc and could not compile OpenCV header filess.

1) How can i include OpenCV3.1.0 library into .cu file?

score 2 · Answer 1 · answered Jul 04 '16 at 13:34

You don't need to include OpenCV in .cu file. You need a Caller API with raw pointers and basic data types as parameters.

main.cpp

#include "opencv2/opencv.hpp"
#include "medianFilter.h"

int main() {
  cv::Mat inputMat = cv::imread();
  .....
  cudaMedianCaller (d_inputMat, d_kernelMat);
  .....
  return 0;
}

medianFilter.h

cudaMedianCaller (uchar3* d_inputMat, uchar* d_kernelMat);

medianFilter.cu

cudaMedianCaller (uchar3* d_inputMat, uchar* d_kernelMat)
{
    kernelMedianFilter<<< , >>> (uchar3* d_inputMat, uchar* d_kernelMat)
}

__global__ void kernelMedianFilter (uchar3* d_inputMat, uchar* _kernelMat)
{

}

Thanks a lot. I test your file with my code and then report to you. — AmiR Hossein, Jul 04 '16 at 19:17

WDC · Answer 2 · 2018-10-22T12:33:24.027

Despite the other good answer that suggests separation between C++ and CUDA, there is an alternative way to include OpenCV containers in .cu files:

CMakeLists.txt

cmake_minimum_required(VERSION 3.8)
project(test LANGUAGES CXX CUDA)
find_package(OpenCV 3.0 REQUIRED)

# compile the target
add_executable(test_app main.cpp medianFilter.cu)
target_link_libraries(test_app PRIVATE cudart ${OpenCV_LIBS})

main.cpp

#include "opencv2/opencv.hpp"
#include "medianFilter.h"

int main()
{
    // input data
    cv::Mat inputMat(cv::Size(128, 128), CV_8UC3, cv::Scalar(100));
    cv::Mat kernelMat(cv::Size(16, 16), CV_8UC1, cv::Scalar(1));

    // call CUDA
    cudaMedianCaller(inputMat, kernelMat);
    return 0;
}

medianFilter.cu

#include "medianFilter.h"
__global__ void kernelMedianFilter(uchar3* d_inputMat, uchar* d_kernelMat)
{
    return;
}
void cudaMedianCaller(const cv::Mat& inputMat, cv::Mat& kernelMat)
{
    // allocate device pointers
    uchar3 *d_inputMat;
    uchar  *d_kernelMat;
    cudaMalloc(&d_inputMat,  inputMat.total() * sizeof(uchar3));
    cudaMalloc(&d_kernelMat, kernelMat.total() * sizeof(uchar));

    // copy from host to device
    cudaMemcpy(d_inputMat, inputMat.ptr<uchar3>(0), inputMat.total() * sizeof(uchar3), cudaMemcpyHostToDevice);
    cudaMemcpy(d_kernelMat, kernelMat.ptr<uchar>(0), kernelMat.total() * sizeof(uchar), cudaMemcpyHostToDevice);

    // call CUDA kernel
    kernelMedianFilter <<<1, 1>>> (d_inputMat, d_kernelMat);

    // free
    cudaFree(d_inputMat);
    cudaFree(d_kernelMat);
}

medianFilter.h

#include "opencv2/opencv.hpp"
void cudaMedianCaller (const cv::Mat& inputMat, cv::Mat& kernelMat);

For the binary application to run, you may need to copy some of the required .dll to the binary folder. For me, I copied opencv_core343.dll from C:\Program Files\OpenCV\x64\vc15\bin to the folder where test_app.exe exists.

How to include and use OpenCv3.1.0 library to CUDA file(.cu)?

2 Answers2

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