This little screenshot explains well the issue. I have shapes from Photoshop (also made a test from copying shapes from Illustrator) and exporting to PDF.
Here is the ugly results. If I reduce the size of the shape it becomes uglier.
Any help ?
Alright, I found a solution. It seems that the problem comes from Automate-PDF Presentation... When I use this tool to create my pdf, the shapes are deformed.
But if I export every pages separately in PDF format using Save As... there is no problem.
Then to merge all the pages I use an online webservice.
I agree that this is not really an explanation but more a workaround.