If you select the Export graphs to HTML item, you can click the Next button and see the following window:

You must select the graph(s) and specify to which output directory the selected graph(s) should be exported. You can also generate index file of the exported pages and corresponding graphs and/or images of the selected graphs. By switching the radio buttons, you are selecting either the scale of the output images, or the width and the height of the images. You can decide whether antialiasing should be used.