AlternateContent Elements Wrapping Ink Annotations Are Removed when Presentation Is Saved

Scenario: The app opens PowerPoint presentations, makes some manipulations and saves files back in the original format. Some presentations have ink annotations. Tested on the latest Aspose.Slide 21.10.

Issue: The structure of a slide is changed on save.

Each ink annotation on a slide is represented by the contentPart element that references custom XML part (one contentPart element and one custom XML part for each ink annotation).

MS PowerPoint wraps each contentPart with AlternateContent containing picture in the Fallback element. This is done for applications and older versions of PowerPoint, that do not support ink annotations. Such applications simply show image from the "Fallback element.

Aspose.Slides removes parent AlternateContent element, leaving only contentPart. (35.7 KB)

var p= new Presentation(@"sample.pptm");
doc.Save(@"sample-resaved.pptm", SaveFormat.Pptm);

original.png (22.8 KB)
resaved.png (25.6 KB)

For internal reference: MDP-12859.


Thank you for contacting support and technical details.

Could you please share a screenshot demonstrating the problem you described?

added screenshots to the first post.

I am sorry for the misunderstanding. Please share the screenshot demonstrating the problem with displaying the presentation in PowerPoint. Also, please specify the version of PowerPoint you used.

I do not have such a screenshot for you.

My purpose was to report that Aspose.Slides generates different XML for ink annotations by removing parts generated by PowerPoint for a reason.

Aspose must have a good reason for removing AlternateContent. Aspose must not assume that all files will always be opened by the PowerPoint that supports ink annotations. There is plenty of editors/viewers (+ older versions of PowerPoint) that might not support ink annotations.

1 Like

I agree with your arguments but Aspose.Slides does not guarantee that generated document structure will be the same as that created by PowerPoint. The most important thing is that the document is displayed correctly with PowerPoint and with other viewers. That’s why we need the screenshot with the problem of a document displaying to investigate this case.