Recent versions of Aspose.slides Java don’t convert the attached .pptx file to PDF correctly: the image at page 2 is missing. Tested with v19.4 and v19.5.
Tried both normal PDF output and PDF_A_1b.
Source code attached as ZIP, together with .pptx file to replicate the behavior.AsposeSlidesMissingImage.zip (2.1 MB)
I have worked with the presentation file shared by you and have been able to observe the issue. An issue with ID SLIDESJAVA-37673 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 the issue will be fixed.