v3

imgcpy.cpp

@@ -0,0 +1,65 @@
+#include "opencv2/opencv.hpp"
+
+int main() {
+    cv::Mat testImg = cv::imread("../img1.png", cv::IMREAD_COLOR); // BGR
+    cv::cvtColor(testImg, testImg, cv::COLOR_BGR2RGBA);
+    std::cout << "The number of channels: " << testImg.channels() << std::endl;
+    if (testImg.type() == CV_8UC1){
+        std::cout << "The image type is: CV_8UC1" << std::endl;
+    }
+//    cv::Rect ROI(0, 0, 50, 50);
+//    testImg = testImg(ROI);
+    cv::imshow("test", testImg);
+    cv::waitKey(0);
+
+//    auto copyData = testImg.clone().data;
+//    cv::Mat imgCopy(testImg.rows, testImg.cols, CV_8UC1, copyData);
+//    cv::imshow("image copy", imgCopy);
+//    cv::waitKey(0);
+
+
+    std::cout << "The first 9 elements of the Mat array: " << std::endl;
+    std::cout << "The matrix obtained values: " << std::endl;
+    for (int i = 0; i < 3; i++){
+        std::cout << testImg.at<cv::Vec4b>(i, i) << " ";
+    }
+
+    std::cout << std::endl << "The array obtained value: " << std::endl;
+    for (int i = 0; i < 16; i++){
+         std::cout << (int)testImg.data[i] << " ";
+    }
+    std::cout << std::endl;
+
+//    for (int i = 0; i < 50; i++){
+//        for (int j = 0; j < 50; j++){
+//            std::cout << testImg.data[j*i + j] << " ";
+//        }
+//        std::cout << std::endl;
+//    }
+
+    auto* p_data = (uint8_t*)malloc(testImg.cols*testImg.rows * testImg.channels() * sizeof(uint8_t));
+    auto xres = testImg.cols;
+    auto yres = testImg.rows;
+    uint8_t color = 255;
+//    for (int i = 0; i < yres; ++i)
+//    {
+//        for (int j = 0; j < xres; ++j){
+//            memcpy(p_data + (i+j) * sizeof(uchar), testImg.data + (i+j) * sizeof(uchar), sizeof(color));
+//
+//        }
+//    }
+    auto memsize = testImg.cols*testImg.rows * testImg.channels() * sizeof(uint8_t);
+    // In order to make a proper copy of the image, you need to pass the pointer to its COPY, not ITSELF.
+    memcpy(p_data, (uint8_t*)testImg.clone().data, memsize);
+    std::cout << std::endl;
+    for (int i = 0; i < 50; i++){
+        for (int j = 0; j < 50; j++){
+            std::cout << (int)p_data[j*i + j] << " ";
+        }
+        std::cout << std::endl;
+    }
+    cv::Mat recImg(yres, xres, CV_8UC4, p_data);
+    cv::imshow("recovered image", recImg);
+    cv::waitKey(0);
+
+}