Speed up scrolling with keyboard (up/down key) through a list of large image files

Ideas for improvements and requests for new features in XnView MP

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ThomasLandauer
Posts: 11
Joined: Sat Jul 22, 2017 7:11 pm

Speed up scrolling with keyboard (up/down key) through a list of large image files

Post by ThomasLandauer »

In the main window (i.e. images list), "scrolling" over large images with the keyboard (i.e. either by holding the up/down key, or by pressing it repeatedly) is very slow. The reason seems to be that XnView is decoding each image, before advancing the cursor bar to the next image.
My idea to make this faster: Before starting to decode an image, check if another keypress was received. If yes, don't decode it at all, and just move the cursor bar.
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helmut
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Joined: Sun Oct 12, 2003 6:47 pm
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Re: Speed up scrolling with keyboard (up/down key) through a list of large image files

Post by helmut »

Thank you, Thomas, for your suggestion. AFAIK, XnView has various speed optimizations including your suggested "check for additional key press". By default, XnView caches generated thumbnails so the problem that you experience should only happen the very first time you browse a folder.

I assume that you know that there is "Page up" and "Page down" keys for pagewise scrolling. Though, I'm not quite sure whether this will be much faster in your case.