OpenCV代码提取：merge/split函数的实现

对OpenCV中的merge/split函数进行了实现，经测试，与OpenCV3.1结果完全一致。

merge实现代码merge.hpp：

// fbc_cv is free software and uses the same licence as OpenCV
// Email: fengbingchun@163.com#ifndef FBC_CV_MERGE_HPP_
#define FBC_CV_MERGE_HPP_/* reference: include/opencv2/core.hppcore/src/convert.cppcore/src/merge.cpp
*/#include <vector>
#include "core/mat.hpp"#ifndef __cplusplus#error merge.hpp header must be compiled as C++
#endifnamespace fbc {// merge several arrays to make a single multi-channel array
template<typename _Tp, int chs1, int chs2>
int merge(const std::vector<Mat_<_Tp, chs1>>& src, Mat_<_Tp, chs2>& dst)
{FBC_Assert(dst.data != NULL);FBC_Assert((src.size() > 0) && (src.size() == dst.channels) && (src.size() <= FBC_CN_MAX));int width = src[0].cols;int height = src[0].rows;FBC_Assert((dst.cols == width) && (dst.rows == height));for (int i = 0; i < src.size(); i++) {FBC_Assert(src[i].data != NULL);FBC_Assert((src[i].cols == width) && src[i].rows == height);FBC_Assert(src[i].channels == 1);}if (src.size() == 1) {memcpy(dst.data, src[0].data, dst.step * dst.rows);return 0;}_Tp* pDst = (_Tp*)dst.data;int len = width * height;int cn = dst.channels;for (int i = 0; i < src.size(); i++) {_Tp* pSrc = (_Tp*)src[i].data;for (int j = 0; j < len; j++) {pDst[j * cn + i] = pSrc[j];}}return 0;
}} // namespace fbc#endif // FBC_CV_MERGE_HPP_

split实现代码split.hpp：

// fbc_cv is free software and uses the same licence as OpenCV
// Email: fengbingchun@163.com#ifndef FBC_CV_SPLIT_HPP_
#define FBC_CV_SPLIT_HPP_/* reference: include/opencv2/core.hppcore/src/convert.cppcore/src/split.cpp
*/#include <vector>
#include "core/mat.hpp"#ifndef __cplusplus#error split.hpp header must be compiled as C++
#endifnamespace fbc {// split a multi-channel array into separate single-channel arrays
template<typename _Tp, int chs1, int chs2>
int split(const Mat_<_Tp, chs1>& src, std::vector<Mat_<_Tp, chs2>>& dst)
{FBC_Assert(src.data != NULL);FBC_Assert((dst.size() == chs1) && (chs2 == 1));for (int i = 0; i < dst.size(); i++) {FBC_Assert((dst[i].data != NULL) && (dst[i].rows == src.rows) && (dst[i].cols == src.cols));}int cn = src.channels;if (cn == 1) {memcpy(dst[0].data, src.data, src.step * src.rows);return 0;}_Tp* pSrc = (_Tp*)src.data;int len = src.rows * src.cols;for (int i = 0; i < cn; i++) {_Tp* pDst = (_Tp*)dst[i].data;for (int j = 0; j < len; j++) {pDst[j] = pSrc[j * cn + i];}}return 0;
}} // namespace fbc#endif // FBC_CV_SPLIT_HPP_

merge测试代码：

#include <assert.h>
#include <vector>
#include <core/mat.hpp>
#include <merge.hpp>#include <opencv2/opencv.hpp>#include "test_merge.hpp"int test_merge_uchar()
{cv::Mat matSrc1 = cv::imread("E:/GitCode/OpenCV_Test/test_images/lena.png", 1);cv::Mat matSrc2 = cv::imread("E:/GitCode/OpenCV_Test/test_images/1.jpg", 1);cv::Mat matSrc3 = cv::imread("E:/GitCode/OpenCV_Test/test_images/2.jpg", 1);if (!matSrc1.data || !matSrc2.data || !matSrc3.data) {std::cout << "read image fail" << std::endl;return -1;}int width = 500, height = 600;cv::cvtColor(matSrc1, matSrc1, CV_BGR2GRAY);cv::cvtColor(matSrc2, matSrc2, CV_BGR2GRAY);cv::cvtColor(matSrc3, matSrc3, CV_BGR2GRAY);cv::resize(matSrc1, matSrc1, cv::Size(width, height));cv::resize(matSrc2, matSrc2, cv::Size(width, height));cv::resize(matSrc3, matSrc3, cv::Size(width, height));fbc::Mat_<fbc::uchar, 1> mat1(height, width, matSrc1.data);fbc::Mat_<fbc::uchar, 1> mat2(height, width, matSrc2.data);fbc::Mat_<fbc::uchar, 1> mat3(height, width, matSrc3.data);std::vector<fbc::Mat_<fbc::uchar, 1>> mat;mat.push_back(mat1);mat.push_back(mat2);mat.push_back(mat3);fbc::Mat_<fbc::uchar, 3> matDst(height, width);fbc::merge(mat, matDst);std::vector<cv::Mat> mat_;mat_.push_back(matSrc1);mat_.push_back(matSrc2);mat_.push_back(matSrc3);cv::Mat matDst_;cv::merge(mat_, matDst_);assert(matDst.channels == matDst_.channels());assert((matDst.rows == matDst_.rows) && (matDst.cols == matDst_.cols));assert(matDst.step == matDst_.step);for (int i = 0; i < matDst.rows; i++) {const fbc::uchar* p1 = matDst.ptr(i);const uchar* p2 = matDst_.ptr(i);for (int j = 0; j < matDst.step; j++) {assert(p1[j] == p2[j]);}}return 0;
}int test_merge_float()
{cv::Mat matSrc1 = cv::imread("E:/GitCode/OpenCV_Test/test_images/lena.png", 1);cv::Mat matSrc2 = cv::imread("E:/GitCode/OpenCV_Test/test_images/1.jpg", 1);cv::Mat matSrc3 = cv::imread("E:/GitCode/OpenCV_Test/test_images/2.jpg", 1);if (!matSrc1.data || !matSrc2.data || !matSrc3.data) {std::cout << "read image fail" << std::endl;return -1;}int width = 500, height = 600;cv::cvtColor(matSrc1, matSrc1, CV_BGR2GRAY);cv::cvtColor(matSrc2, matSrc2, CV_BGR2GRAY);cv::cvtColor(matSrc3, matSrc3, CV_BGR2GRAY);cv::resize(matSrc1, matSrc1, cv::Size(width, height));cv::resize(matSrc2, matSrc2, cv::Size(width, height));cv::resize(matSrc3, matSrc3, cv::Size(width, height));matSrc1.convertTo(matSrc1, CV_32FC1);matSrc2.convertTo(matSrc2, CV_32FC1);matSrc3.convertTo(matSrc3, CV_32FC1);fbc::Mat_<float, 1> mat1(height, width, matSrc1.data);fbc::Mat_<float, 1> mat2(height, width, matSrc2.data);fbc::Mat_<float, 1> mat3(height, width, matSrc3.data);std::vector<fbc::Mat_<float, 1>> mat;mat.push_back(mat1);mat.push_back(mat2);mat.push_back(mat3);fbc::Mat_<float, 3> matDst(height, width);fbc::merge(mat, matDst);std::vector<cv::Mat> mat_;mat_.push_back(matSrc1);mat_.push_back(matSrc2);mat_.push_back(matSrc3);cv::Mat matDst_;cv::merge(mat_, matDst_);assert(matDst.channels == matDst_.channels());assert((matDst.rows == matDst_.rows) && (matDst.cols == matDst_.cols));assert(matDst.step == matDst_.step);for (int i = 0; i < matDst.rows; i++) {const fbc::uchar* p1 = matDst.ptr(i);const uchar* p2 = matDst_.ptr(i);for (int j = 0; j < matDst.step; j++) {assert(p1[j] == p2[j]);}}return 0;
}

split测试代码：

#include <assert.h>
#include <vector>
#include <core/mat.hpp>
#include <split.hpp>#include <opencv2/opencv.hpp>#include "test_split.hpp"int test_split_uchar()
{cv::Mat mat = cv::imread("E:/GitCode/OpenCV_Test/test_images/lena.png", 1);if (!mat.data) {std::cout << "read image fail" << std::endl;return -1;}//cv::cvtColor(mat, mat, CV_BGR2GRAY);int chs = mat.channels();int width = mat.cols;int height = mat.rows;fbc::Mat_<fbc::uchar, 3> mat1(height, width, mat.data);std::vector<fbc::Mat_<fbc::uchar, 1>> vecMat2;fbc::Mat_<fbc::uchar, 1>* mat2 = new fbc::Mat_<fbc::uchar, 1>[chs];for (int i = 0; i < chs; i++) {mat2[i] = fbc::Mat_<fbc::uchar, 1>(height, width);vecMat2.push_back(mat2[i]);}fbc::split(mat1, vecMat2);cv::Mat mat1_(height, width, CV_8UC3, mat.data);std::vector<cv::Mat> vecMat2_;cv::split(mat1_, vecMat2_);assert(vecMat2.size() == vecMat2_.size());for (int i = 0; i < vecMat2.size(); i++) {assert(vecMat2[i].rows == vecMat2_[i].rows && vecMat2[i].cols == vecMat2_[i].cols);assert(vecMat2[i].step == vecMat2_[i].step);assert(vecMat2[i].channels == vecMat2_[i].channels());for (int y = 0; y < vecMat2[i].rows; y++) {const fbc::uchar* p = vecMat2[i].ptr(y);const uchar* p_ = vecMat2_[i].ptr(y);for (int x = 0; x < vecMat2[i].step; x++) {assert(p[x] == p_[x]);}}}delete[] mat2;return 0;
}int test_split_float()
{cv::Mat mat = cv::imread("E:/GitCode/OpenCV_Test/test_images/lena.png", 1);if (!mat.data) {std::cout << "read image fail" << std::endl;return -1;}mat.convertTo(mat, CV_32FC3);//cv::cvtColor(mat, mat, CV_BGR2GRAY);int chs = mat.channels();int width = mat.cols;int height = mat.rows;fbc::Mat_<float, 3> mat1(height, width, mat.data);std::vector<fbc::Mat_<float, 1>> vecMat2;fbc::Mat_<float, 1>* mat2 = new fbc::Mat_<float, 1>[chs];for (int i = 0; i < chs; i++) {mat2[i] = fbc::Mat_<float, 1>(height, width);vecMat2.push_back(mat2[i]);}fbc::split(mat1, vecMat2);cv::Mat mat1_(height, width, CV_32FC3, mat.data);std::vector<cv::Mat> vecMat2_;cv::split(mat1_, vecMat2_);assert(vecMat2.size() == vecMat2_.size());for (int i = 0; i < vecMat2.size(); i++) {assert(vecMat2[i].rows == vecMat2_[i].rows && vecMat2[i].cols == vecMat2_[i].cols);assert(vecMat2[i].step == vecMat2_[i].step);assert(vecMat2[i].channels == vecMat2_[i].channels());for (int y = 0; y < vecMat2[i].rows; y++) {const fbc::uchar* p = vecMat2[i].ptr(y);const uchar* p_ = vecMat2_[i].ptr(y);for (int x = 0; x < vecMat2[i].step; x++) {assert(p[x] == p_[x]);}}}delete[] mat2;return 0;
}

GitHub： https://github.com/fengbingchun/OpenCV_Test