Force thumbnail building on directories with thousands of files

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jellen
Posts: 6
Joined: Thu Jan 18, 2018 9:49 pm

Force thumbnail building on directories with thousands of files

Post by jellen »

Hi there-

We are trying to use XnView MP to look at directories with many files (10,000+) . I am generating these images from a scientific instrument.

They are in .png format, so I do not believe there is any embedded thumbnail as there would be with .jpg.

Once I render the images, they don't change. So what I would like to do is be able to open XnView, point it at a root directory of a project, and tell it to 'render thumbnails' or whatever it needs to do overnight. There are many options under settings that look applicable, but they don't seem to make any difference. For example, under settings->thumbnail, there's an option for 'Create Thumbnails for whole folder', but whether or not I have that checked, it doesn't seem to make a difference. There's an option for 'create high quality thumbnail', and I have turned that off, but I don't know that it helps go any faster.

Under settings->catalog, I have enabled the catalog. I have increased the memory usage for database engine from 50MiB to 500MiB. I have 'enable thumbnail caching' turned on. I tried setting the 'base path of your pictures', but that doesn't seem to do it (or maybe I haven't waited long enough yet).

When I look at the cached directory listing, it immediately says that one particular directory has 34,187 files, and the size of the cache is 131.85 MiB. However, when I scroll around that folder, XnView is definitely still rendering thumbnails, because they do not all display immediately, there is a lot of waiting. But that number never goes up. So is that just the size of all the thumbnails once they are eventually rendered? What else can I do to try to scroll through a very large folder faster?

Ultimately, it is not very useful to scroll through 30,000+ images to look for anything. I would prefer to be able to filter these images by different queries ( as requested here: viewtopic.php?f=110&t=36957 ). But until then, looking at large directories is the only choice.

Any suggestions?

Thanks.
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xnview
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Joined: Mon Oct 13, 2003 7:31 am
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Re: Force thumbnail building on directories with thousands of files

Post by xnview »

you have settings>Catalog>Rebuild thumbnails (for all folders already in the catalog)
Pierre.
icancomplain
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Joined: Fri Oct 08, 2021 2:48 pm

Re: Force thumbnail building on directories with thousands of files

Post by icancomplain »

I know this is an old post, but I have the same need and am unsure how to go about it. I want all the thumbnails to be built ahead of time for fast browsing, but they only build when I go into that subdirectory. I have a "Pictures" directory with hundreds of subdirectories. I could add each subdirectory one-by-one to the "Catalog" settings area, but that would take forever. You can't select-all on the subdirectories. I've set the base directory to "Pictures" and I've also put it on the "included" list. Thank you for your time.

Daniel
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xnview
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Joined: Mon Oct 13, 2003 7:31 am
Location: France

Re: Force thumbnail building on directories with thousands of files

Post by xnview »

icancomplain wrote: Fri Oct 08, 2021 2:57 pm I know this is an old post, but I have the same need and am unsure how to go about it. I want all the thumbnails to be built ahead of time for fast browsing, but they only build when I go into that subdirectory. I have a "Pictures" directory with hundreds of subdirectories. I could add each subdirectory one-by-one to the "Catalog" settings area, but that would take forever. You can't select-all on the subdirectories. I've set the base directory to "Pictures" and I've also put it on the "included" list. Thank you for your time.
Do you use same database on multiple PC? If no, no need to use 'base path'
If you use 'add folder' in settings>Catalog?
Pierre.
icancomplain
Posts: 3
Joined: Fri Oct 08, 2021 2:48 pm

Re: Force thumbnail building on directories with thousands of files

Post by icancomplain »

xnview wrote: Fri Oct 08, 2021 3:21 pm
Do you use same database on multiple PC? If no, no need to use 'base path'
If you use 'add folder' in settings>Catalog?
Not used on multiple PC's. I will remove the 'base path'. The "Pictures" directory shows in the list on the "Catalog" settings tab and I guess the subdirectories that I have gone into. None of the other subdirectories are there. I don't know if they are supposed to or if there is some recursive box I'm supposed to check instead. I'm not at my computer right now, but will be in an hour or two to try again. Thank you.
icancomplain
Posts: 3
Joined: Fri Oct 08, 2021 2:48 pm

Re: Force thumbnail building on directories with thousands of files

Post by icancomplain »

I think it's generating the thumbnails now.

This is why it's confusing...

On the Settings->Catalog tab in the list of directories, I can see /Volumes/PicturesDP/Pictures/ which is the directory I want. It's showing up there maybe just because I clicked on it manually in the Folder explorer area or for some other reason. However, that is not a formal "import" which seems to be necessary to get it to create the thumbnails. So to my untrained eye, I'm basically having to add the Pictures directory to the Catalog list a second time, which is counter-intuitive. It probably shouldn't show there the first time, like maybe you should be required to "import" to begin with for it to show up there. To me, it would be great to visualize a folder tree with checkboxes or icons or something showing you which folders you have imported and which ones you don't. It would be the easiest way for a user to see what is there and you could check or uncheck a directory so you don't have to see it.