Hello Marco,
It turns out that a known limitation causes this, the JPXDecode filter is not supported. We already have a feature request for this. You can track its progress, subscribe to status changes, and add your comment to it here: PdfProcessing: Add support for JPXDecode Filter.
The above link contains a workaround as well.
I want to apologize for the inconvenience this is causing you.
Regards,
Dimitar
Progress Telerik
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