Preview shows squashed image in PDF's signed with PAdES signatures

Number:rdar://37869269 Date Originated:February 25 2018, 7:11 PM
Status:Open Resolved:
Product:Preview Product Version:Preview Version 10.0 (944.4)
Classification: Reproducible:Yes
Preview shows incorrect image width and height for the visual representation of a PAdES signature.

Steps to Reproduce:
Open the attached PDF in Preview

Expected Results:
See the screenshot of Adobe Reader DC compared to Preview. Also all other readers we've tried show the image correctly.

Actual Results:
The bounding box of the signature seems to be correct (when you select the signature). However the image inside of the bounding box is squashed. See screenshots.

Preview Version 10.0 (944.4) but also happens in older versions.

Both settings of 'Define 100% scale as:' give the same results.

simple_pdf.pdf is the original unsigned file for reference. simple_pdf.pdf_python_appended_after_signature_1.pdf is the file that shows the wrong image.
signature_stamp.png is the image that is used in the visual representation of the signature.


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