Images have artifacts in PDF export

Simon-Buijs wrote on 3/22/2022, 7:25 AM

I've inserted a couple of images onto my page and in the editor they look fine (picture below).

However when I export to PDF the images seem to have some unexpected artifacts around the edges (picture below).

They disappear when I've zoomed in far enough, but are very apparent when viewed on <400% zoom.

I feel like I've tried everything; different export settings (such as DPI), drawing them myself vs. using ones from google.

When I export the XLD_Introduction document however everything looks fine, so I'm probably doing something wrong somewhere, I just can't figure out what it is.

Does anyone here have any idea what's going on?

I'm using Xara Page & Layout Designer 11 on Windows 11 and my PDF reader is Adobe Acrobat Reader version 2021.011.20039

Comments

johnebaker wrote on 3/22/2022, 4:02 PM

@Simon-Buijs

. . . . They disappear when I've zoomed in far enough, but are very apparent when viewed on <400% zoom . . . .

This is contrary to the norm where such artefacts, when present, become more apparent as you zoom in

Your images posted above are too small to see clearly what is happening.

However i suspect that what you are seeing is a result of anti aliasing images which are of low resolution.

What are the images format, height/width and resolution either as dots per inch/cm or pixels per inch/cm?

What image resolution is set for the PDF export or program settings?

John EB
Forum Moderator

Simon-Buijs wrote on 3/23/2022, 7:35 AM

@johnebaker

Hey John, thanks for your reply!

All images are PNGs, I'm not sure where I can find the dots/pixels per inch/cm.

All images are somewhere between 200x200 and 600x600 (though none of them are exactly square) and take up about 0,5x0,5 cm on the page. Does that answer your question? Or is it an image property I should be able to find somewhere?

I'm also not sure what you mean with image resolution. In the PDF export options I have Rasterization Resolution (DPI) set to 600. When I look at the Bitmap Gallery all images have a DPI of 96.

Something I found out yesterday evening is that when I open my PDF in the browser everything looks fine somehow.

johnebaker wrote on 3/23/2022, 10:43 AM

@Simon-Buijs

The images are big enough in width and height, and the PDF export Rasterization resolution is the standard for PDF files.

Do the PDF's look Ok if you open them with Adobe Acrobat DC?

With all the above this is sounding like the artefacts are a result of the zooming rather than an actual issue with the images.

John EB

Simon-Buijs wrote on 3/25/2022, 6:50 AM

@johnebaker

No the artefacts are showing when I open the PDF with Adobe Acrobat Reader DC. Two things confuse me:

- If I export Xara's own Introduction project with the exact same settings it looks fine, which would suggest there must be something wrong with my images.

- If I open the PDF of my project in the browser it also looks fine, which would suggest the viewer is the issue.