'High Zoom Quality' algorithm

Ideas for improvements and requests for new features in XnView Classic

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Guest

'High Zoom Quality' algorithm

Post by Guest »

My English is very ugly. sorry.

Now XnView's 'High Zoom Quality' algorithm is bilinear.
Can I use lanczos instead of bilinear?
If I can't then add this feature, please.
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xnview
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Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: 'High Zoom Quality' algorithm

Post by xnview »

Guest wrote:My English is very ugly. sorry.

Now XnView's 'High Zoom Quality' algorithm is bilinear.
Can I use lanczos instead of bilinear?
If I can't then add this feature, please.
If i use lanczos, the delay to display it will be more important
Pierre.
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inrobert
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Joined: Mon Nov 27, 2006 10:36 pm

Re: 'High Zoom Quality' algorithm

Post by inrobert »

xnview wrote: If i use lanczos, the delay to display it will be more important
It could be an option for those users who are looking for best quality while viewing pictures and using zoom and don't care much about time. Lanchos is already available in resize so it should be easy to add it as an option to zoom. I am looking for a progam that uses lanczos in view mode and so far I have found only FarStone Image Viewer but unfortunately, though I can choose Lanczos in options for viewing, it gives much worse quality than using Lanczos in the same program but in resize tool (:shock: I can't understand why). ACDSee also allows to choose from resampling algorithm in a viewer but there's no Lanczos (which is the best for downsampling especially). Maybe XnView would be the first with good Lanczos implementation in a viewer. If so, it will be the best graphics browser I know. :D So please add this option for quality lovers. :)
Zoom out with Lanczos - this would be great
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foxyshadis
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Post by foxyshadis »

You can get lanczos and some other methods in Comical, which is a sort of an image viewer... but definitely holds no candle to xnview, except for superior read-ahead caching and resize. But honestly, the only time I've ever needed a sharp resize is reading text (bicubic tends to look better), so comical needs it, but I never felt a need in xnview.

[OT] Speed's all that troubles me, and I know of several implementations of extremely fast assembly/sse optimized resizers, but they can't be directly used since they're GPL. Bah. It's not really too bad though, except that the read-ahead cache could stand to hold the original+resize to make browsing even quicker.