We are using skia in our application for writing PDFs and there seems to be an issue when adding images with opacity.
When opening the pdf in Chrome the opacity of the images looks fine. However, when opening it in Acrobat, Safari or Firefox images have much smaller opacity. It seems like the opacity is applied twice.
Using Acrobat Reader and preflight you can actually see that the transparency gets added (and applied) twice. Once on the image itself and once on the graphic object. A 0.8 opacity therefore results looking like a 0.64 opacity in the pdf.
I've created this simple fiddle: https://fiddle.skia.org/c/be7c61be9475b31dd1aa41a1a221046e
. If you click on PDF and download it, you will end up with a PDF that showcases the issue. It will look good in Chrome, but not in other tools.
I also wrote this fiddle that goes through the whole pdf generation flow: https://fiddle.skia.org/c/b84e4329d2c04d785c05b701463e4bf1
Is this a known issue? Should I file a bug for this?