Artifacts when zooming .PNG files with transparent background in MP version

Bugs which have been reproduced by a second user or the developer, or features to do

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therealjoeblow
Posts: 9
Joined: Tue Dec 27, 2011 8:16 pm

Artifacts when zooming .PNG files with transparent background in MP version

Post by therealjoeblow »

When I view .PNG files with transparent backgrounds, if the zoom is set to 100%, then they display properly with no issue. For example any kind of logo file.

However if I zoom them either up or down by any amount, they are full of weird artifacts.

XnView Classic does not have this problem, it displays the images perfectly without any artifacts no matter what the zoom level is. Just the MP version has this issue. And it's had it forever, since years way back and is still there in the current version.

Image

Image

Image

Could you please fix this so the .PNG's display properly at any zoom level?

Thx
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xnview
Author of XnView
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Joined: Mon Oct 13, 2003 7:31 am
Location: France
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Re: Artifacts when zooming .PNG files with transparent background in MP version

Post by xnview »

Please send the file
Pierre.
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therealjoeblow
Posts: 9
Joined: Tue Dec 27, 2011 8:16 pm

Re: Artifacts when zooming .PNG files with transparent background in MP version

Post by therealjoeblow »

You can grab it here:

https://thetvdb.com/series/the-serpent-queen#artwork

Click the "clearlogo" tab...
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therealjoeblow
Posts: 9
Joined: Tue Dec 27, 2011 8:16 pm

Re: Artifacts when zooming .PNG files with transparent background in MP version

Post by therealjoeblow »

But it's not just that particular logo, it's every one...

Here's another...

https://thetvdb.com/series/the-sinner#artwork
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therealjoeblow
Posts: 9
Joined: Tue Dec 27, 2011 8:16 pm

Re: Artifacts when zooming .PNG files with transparent background in MP version

Post by therealjoeblow »

And another...

https://thetvdb.com/series/the-peripheral#artwork

Well, you get the idea...
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user0
XnThusiast
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Joined: Sat May 09, 2015 9:37 am

Re: Artifacts when zooming .PNG files with transparent background in MP version

Post by user0 »

png truecolor+alpha
high zoom quality (any, except None and Bilinear) + zoom
test_img_rgb+alpha.png


related
1.7.1 - viewer - high zoom quality - border at the edge of transparent png
1.8.2 - view - png - tRNS transparency - viewing issues (test img 10)
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therealjoeblow
Posts: 9
Joined: Tue Dec 27, 2011 8:16 pm

Re: Artifacts when zooming .PNG files with transparent background in MP version

Post by therealjoeblow »

Not sure what that cryptic reply means?

Can you be more clear and answer with one of the following?

1) This is a known issue and is going to be fixed
1B) When? Given that XnView standard doesn't do this should be an easy fix?

2) This is a known issue but is not going to be fixed
2B) Why? Outside of the capability of the software? Or what reason?

3) This not an issue, it is operating as intended
3B) Why would it be intended to do that?

Thanks
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Anon3mouse
Posts: 1
Joined: Thu May 01, 2025 6:17 am

Re: Artifacts when zooming .PNG files with transparent background in MP version

Post by Anon3mouse »

Until it's fixed:

Tools>Settings>View

Use checkerboard pattern as background > (enabled)
High Zoom Quality > Make sure "Zoom In" and "Zoom Out" both show "None"

Back in the main Screen, go to View under the title bar. You may have to toggle "Use Alpha Channel" on or off.
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