Created attachment 37995 [details]
PowerPoint with slide, which has a uncopiable picture

Any slide import for pictures fails, if the user edited the picture color using Powerpoint.

In our case the slide contained a colored picture, which was edited to show as grey (Picture Color -> Color Saturation -> 0%)

An sample presentation and code will be uploaded with this ticket.

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Test code:
import org.apache.poi.xslf.usermodel.XMLSlideShow;
import org.apache.poi.xslf.usermodel.XSLFSlide;
import org.springframework.core.io.ClassPathResource;

import java.io.ByteArrayOutputStream;

class Scratch {
    public static void main(String[] args) throws Exception {
        XMLSlideShow targetPresentation = new XMLSlideShow();
        XSLFSlide targetPresentationSlide = targetPresentation.createSlide();

        XMLSlideShow sourcePresentation = new XMLSlideShow(new ClassPathResource("POI_Blip_bug.pptx").getInputStream());
        XSLFSlide sourceSlide = sourcePresentation.getSlides().get(0);

        targetPresentationSlide.getSlideMaster().importContent(sourceSlide.getSlideMaster());
        targetPresentationSlide.getSlideLayout().importContent(sourceSlide.getSlideLayout());

        targetPresentationSlide.importContent(sourceSlide);

        targetPresentation.write(new ByteArrayOutputStream());
    }
}


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Exception in thread "main" java.lang.ClassCastException: class org.apache.poi.ooxml.POIXMLDocumentPart cannot be cast to class org.apache.poi.xslf.usermodel.XSLFPictureData (org.apache.poi.ooxml.POIXMLDocumentPart and org.apache.poi.xslf.usermodel.XSLFPictureData are in unnamed module of loader 'app')
	at org.apache.poi.xslf.usermodel.XSLFSheet.importBlip(XSLFSheet.java:651)
	at org.apache.poi.xslf.usermodel.XSLFPictureShape.copy(XSLFPictureShape.java:385)
	at org.apache.poi.xslf.usermodel.XSLFSheet.wipeAndReinitialize(XSLFSheet.java:455)
	at org.apache.poi.xslf.usermodel.XSLFSheet.importContent(XSLFSheet.java:434)
	at org.apache.poi.xslf.usermodel.XSLFSlide.importContent(XSLFSlide.java:293)