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Slide thumbanil: Japanese characters are rendered wrong (C# .NET Docker)

Hi Aspose. I’m using docker with windows container and i have an issue trying to get a thumbnail of a slide with some japanese characters. Could you please advise? Here you can find a source code:
And the image with results:


I have worked with sample project shared and have observed the snapshot. An issue with ID SLIDESNET-41837 has been created in our issue tracking system to further investigate and resolve the issue. This thread has been linked with the issue so that you may be notified once issue will be fixed.

The issues you have found earlier (filed as SLIDESNET-41837) have been fixed in this update.

Hi, that’s odd but this issue is reproducible on 20.8 version 1.png (25.5 KB)


Actually, the container used by youcontains only one font (“Lucida Console”), which does not have the glyphs necessary for displaying. You can try to install the required font in the container, or use the FontsLoader class, as shown below:

FontsLoader.LoadExternalFonts(new string[] { "fonts" });

using (Presentation pres = new Presentation("wrongChar.pptx"))
    var slide = pres.Slides[0];
    using (Bitmap bmp = slide.GetThumbnail(1, 1))
        bmp.Save(slide.SlideNumber + ".png");

The folder “fonts” in this example must contain “Noto Sans CJK JP” fonts for given presentation.