Question

create a qr code for a programme

Answer 1

#include <stdio.h>
#include <qrencode.h>

void generate_qr_code(const char *text) {
    QRcode *qrcode;
    
    qrcode = QRcode_encodeString(text, 0, QR_ECLEVEL_H, QR_MODE_8, 1);

    if(qrcode != NULL) {
        int x, y;
        for(y = 0; y < qrcode->width; y++) {
            for(x = 0; x < qrcode->width; x++) {
                printf("%s", qrcode->data[y * qrcode->width + x] & 1 ? "██" : "  ");
            }
            printf("\n");
        }
        QRcode_free(qrcode);
    } else {
        printf("Failed to generate QR code.\n");
    }
}

int main() {
    char input_text[256];
    
    printf("Enter text to generate QR code: ");
    fgets(input_text, sizeof(input_text), stdin);
    
    generate_qr_code(input_text);
    
    return 0;
}

Answer 2

#include <opencv2/opencv.hpp>
#include <zbar.h>
#include <stdio.h>

int main() {
    // Initialize OpenCV capture object to capture from default camera (0)
    cv::VideoCapture cap(0);
    
    if (!cap.isOpened()) {
        printf("Error: Could not open the camera.\n");
        return -1;
    }

    // Create an OpenCV Mat object to hold the captured frame
    cv::Mat frame;

    // Initialize ZBar scanner
    zbar::ImageScanner scanner;
    scanner.set_config(zbar::ZBAR_NONE, zbar::ZBAR_CFG_ENABLE, 1);

    while (true) {
        // Capture frame from the camera
        cap >> frame;

        if (frame.empty()) {
            printf("Error: Could not capture frame.\n");
            break;
        }

        // Convert the frame to grayscale
        cv::Mat gray;
        cv::cvtColor(frame, gray, cv::COLOR_BGR2GRAY);

        // Wrap OpenCV image data in a ZBar image
        zbar::Image zbarImage(gray.cols, gray.rows, "Y800", gray.data, gray.cols * gray.rows);

        // Scan the image for QR codes
        int n = scanner.scan(zbarImage);
        if (n > 0) {
            // Extract results
            for (zbar::Image::SymbolIterator symbol = zbarImage.symbol_begin(); symbol != zbarImage.symbol_end(); ++symbol) {
                printf("QR Code detected: %s\n", symbol->get_data().c_str());
            }
        }

        // Display the frame
        cv::imshow("QR Code Scanner", frame);

        // Exit on key press
        if (cv::waitKey(30) >= 0) break;
    }

    // Release the camera
    cap.release();
    return 0;
}