With scaling methods Hermite, Gaussian, Bell, BSpline, Mitchell, Lanczos and Hanning the alpha channel gets removed when resizing an image.
Only Nearest Neighbor and Bilinear work as expected and preserve the alpha channel.
Most scaling algorithms remove alpha channel when resizing an image
Moderators: helmut, XnTriq, xnview, Dreamer
Re: Most scaling algorithms remove alpha channel when resizing an image
i can't reproduce, could you send me a sample image?
Pierre.
Re: Most scaling algorithms remove alpha channel when resizing an image
Yes, I also could not reproduce this issue until I found the image I originally had the problem with. It's just 17x17 pixels in size, but it's not the size that causes this, since the issue can not be reproduced after reencoding the image with XnConvert.
- Attachments
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- but can not be reproduced with this file despite, which should be pixel-identical since it was converted from the file that causes the problem to lossless format with XnConvert.
- Quote_17px_result_.png (344 Bytes) Viewed 906 times
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- Issue can be reproduced with this file.
- Quote_17px.png (10.97 KiB) Viewed 906 times
Re: Most scaling algorithms remove alpha channel when resizing an image
I can't reproduce with the file, could you post a screenshot of resize dialog?
Pierre.
Re: Most scaling algorithms remove alpha channel when resizing an image
Can't reproduce either now. I'm on Arch Linux, no idea why it did not work a few months back. Everything's working fine now.xnview wrote: Mon Jun 14, 2021 8:27 am I can't reproduce with the file, could you post a screenshot of resize dialog?
