【Pybind11】Python调用C++接口（Ubuntu下编译OpenCV）

C++

main.cpp

 

#include<iostream>

 

#include<vector>

 

#include<opencv2/opencv.hpp>

 

#include<pybind11/pybind11.h>

 

#include<pybind11/numpy.h>

 

#include<pybind11/stl.h>

 

#include"mat_warper.h"

 

 

 

namespace py = pybind11;

 

 

 

py::array_t<unsigned char> test_rgb_to_gray(py::array_t<unsigned char>& input) {

 

 

 

cv::Mat img_rgb = numpy_uint8_3c_to_cv_mat(input);

 

cv::Mat dst;

 

cv::cvtColor(img_rgb, dst, cv::COLOR_RGB2GRAY);

 

return cv_mat_uint8_1c_to_numpy(dst);

 

 

 

}

 

 

 

py::array_t<unsigned char> test_gray_canny(py::array_t<unsigned char>& input) {

 

cv::Mat src = numpy_uint8_1c_to_cv_mat(input);

 

cv::Mat dst;

 

cv::Canny(src, dst, 30, 60);

 

return cv_mat_uint8_1c_to_numpy(dst);

 

}

 

 

 

 

 

/*

 

@return Python list

 

*/

 

py::list test_pyramid_image(py::array_t<unsigned char>& input) {

 

cv::Mat src = numpy_uint8_1c_to_cv_mat(input);

 

std::vector<cv::Mat> dst;

 

 

 

cv::buildPyramid(src, dst, 4);

 

 

 

py::list out;

 

for (int i = 0; i < dst.size(); i++)

 

{

 

out.append<py::array_t<unsigned char>>(cv_mat_uint8_1c_to_numpy(dst.at(i)));

 

}

 

 

 

return out;

 

}

 

 

 

PYBIND11_MODULE(cv_demo1, m) {

 

 

 

m.doc() = "Simple opencv demo";

 

 

 

m.def("test_rgb_to_gray", &test_rgb_to_gray);

 

m.def("test_gray_canny", &test_gray_canny);

 

m.def("test_pyramid_image", &test_pyramid_image);

 

 

 

}

 

mat_warper.h

 

#ifndef MAT_WARPER_H_

 

 

 

#include<opencv2/opencv.hpp>

 

#include<pybind11/pybind11.h>

 

#include<pybind11/numpy.h>

 

 

 

namespace py = pybind11;

 

 

 

cv::Mat numpy_uint8_1c_to_cv_mat(py::array_t<unsigned char>& input);

 

 

 

cv::Mat numpy_uint8_3c_to_cv_mat(py::array_t<unsigned char>& input);

 

 

 

py::array_t<unsigned char> cv_mat_uint8_1c_to_numpy(cv::Mat & input);

 

 

 

py::array_t<unsigned char> cv_mat_uint8_3c_to_numpy(cv::Mat & input);

 

 

 

#endif // !MAT_WARPER_H_

 

mat_warper.cpp

 

#include"mat_warper.h"

 

#include <pybind11/numpy.h>

 

 

 

/*

 

Python->C++ Mat

 

*/

 

 

 

 

 

cv::Mat numpy_uint8_1c_to_cv_mat(py::array_t<unsigned char>& input) {

 

 

 

if (input.ndim() != 2)

 

throw std::runtime_error("1-channel image must be 2 dims ");

 

 

 

py::buffer_info buf = input.request();

 

 

 

cv::Mat mat(buf.shape[0], buf.shape[1], CV_8UC1, (unsigned char*)buf.ptr);

 

 

 

return mat;

 

}

 

 

 

 

 

cv::Mat numpy_uint8_3c_to_cv_mat(py::array_t<unsigned char>& input) {

 

 

 

if (input.ndim() != 3)

 

throw std::runtime_error("3-channel image must be 3 dims ");

 

 

 

py::buffer_info buf = input.request();

 

 

 

cv::Mat mat(buf.shape[0], buf.shape[1], CV_8UC3, (unsigned char*)buf.ptr);

 

 

 

return mat;

 

}

 

 

 

 

 

/*

 

C++ Mat ->numpy

 

*/

 

py::array_t<unsigned char> cv_mat_uint8_1c_to_numpy(cv::Mat& input) {

 

 

 

py::array_t<unsigned char> dst = py::array_t<unsigned char>({ input.rows,input.cols }, input.data);

 

return dst;

 

}

 

 

 

py::array_t<unsigned char> cv_mat_uint8_3c_to_numpy(cv::Mat& input) {

 

 

 

py::array_t<unsigned char> dst = py::array_t<unsigned char>({ input.rows,input.cols,3}, input.data);

 

return dst;

 

}

 

 

 

 

 

 

 

//PYBIND11_MODULE(cv_mat_warper, m) {

 

//

 

// m.doc() = "OpenCV Mat -> Numpy.ndarray warper";

 

//

 

// m.def("numpy_uint8_1c_to_cv_mat", &numpy_uint8_1c_to_cv_mat);

 

// m.def("numpy_uint8_1c_to_cv_mat", &numpy_uint8_1c_to_cv_mat);

 

//

 

//

 

//}

 

Python调用

 

import cv2

 

import matplotlib.pyplot as plt

 

import demo11.cv_demo1 as cv_demo1

 

import numpy as np

 

 

 

 

 

image_rgb = cv2.imread('F:\\lena\\lena_rgb.jpg', cv2.IMREAD_UNCHANGED)

 

image_gray = cv2.imread('F:\\lena\\lena_gray.jpg', cv2.IMREAD_UNCHANGED)

 

 

 

var1 = cv_demo1.test_rgb_to_gray(image_rgb)

 

print(var1.shape)

 

plt.figure('rgb-gray')

 

plt.imshow(var1, cmap=plt.gray())

 

 

 

var2 = cv_demo1.test_gray_canny(image_gray)

 

plt.figure('canny')

 

plt.imshow(var2, cmap=plt.gray())

 

 

 

var3 = cv_demo1.test_pyramid_image(image_gray)

 

var3 = var3[1:]

 

plt.figure('pyramid_demo')

 

for i, image in enumerate(var3, 1):

 

plt.subplot(2, 2, i)

 

plt.axis('off')

 

plt.imshow(image, cmap=plt.gray())

 

 

 

plt.show()

 

ref：

Linux下编译安装OpenCV(基于C++，生成so库供python调用)

https://blog.csdn.net/non_hercules/article/details/105095153