JKQtPlotter/test/simpletest_rgbimageplot_qt/README.md

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JKQtPlotter

QImage as a Graph

This project (see ./test/simpletest_rgbimageplot_qt/) simply creates a JKQtPlotter widget (as a new window) and adds an image plot with an image taken from a QImage object.

The source code of the main application is (see jkqtplotter_simpletest_rgbimageplot_qt.cpp. the main parts are:

    // 2. now we open a BMP-file and load it into an OpenCV cv::Mat
    QImage image(":/example.bmp");

    // 3. create a graph (JKQTPImage) with a pointer to the QImage-object, generated above
    JKQTPImage* graph=new JKQTPImage(&plot);
    graph->set_title("");
    // copy the image into the graph (optionally you could also give a pointer to a QImage,
    // but then you need to ensure that the QImage is available as long as the JKQTPImage
    // instace lives)
    graph->set_image(image);
    // where does the image start in the plot, given in plot-axis-coordinates (bottom-left corner)
    graph->set_x(0);
    graph->set_y(0);
    // width/height of the image in plot coordinates
    graph->set_width(image.width());
    graph->set_height(image.height());

    // 4. add the graphs to the plot, so it is actually displayed
    plot.addGraph(graph);

The result looks like this:

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