Background of some PNG not shown?

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Micha
Posts: 72
Joined: Thu Feb 08, 2007 12:51 pm

Background of some PNG not shown?

Post by Micha » Tue Sep 03, 2019 1:30 pm

Hi,

if I select a PNG at the browser than I can enable/disable the background of a PNG per Ctrl+H (preview). But some times no background image is shown, most at large images. Here an example. It's downscaled the image for upload, but the problem is still there. I can double click on the image, it's opened at XnView and switch the ocean background on/off. But for the XnView preview the switch doesn't work. Did I have overseen an option?

Best-
Micha
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48_2.png

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xnview
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Re: Background of some PNG not shown?

Post by xnview » Tue Sep 03, 2019 1:47 pm

the problem is in alpha channel
Pierre.

Micha
Posts: 72
Joined: Thu Feb 08, 2007 12:51 pm

Re: Background of some PNG not shown?

Post by Micha » Tue Sep 03, 2019 2:03 pm

Sorry, I don't understand.

The alpha can be enabled/disabled if the image is opened at XnView and the ocean background can be seen. So, it looks like expected. Only the small preview doesn't work in the same way.

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Re: Background of some PNG not shown?

Post by xnview » Tue Sep 03, 2019 2:10 pm

oh right, seems to be a bug with lower zoom value. if > 100%, no problem.
Pierre.

Micha
Posts: 72
Joined: Thu Feb 08, 2007 12:51 pm

Re: Background of some PNG not shown?

Post by Micha » Tue Sep 03, 2019 2:28 pm

I found the issue for large images first (like 6000x4000), for smaller it works. I was surprised that the down scaled image shows the problem too, but so it was able to upload it here.

Good luck for fixing.

Thanks,
Micha

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