Currently the max thumbnail size is 256px. My screen's resolution is 3840x2160, so the largest I can get is approx 5 rows x 8 columns. For a folder of images, sometimes I want to preview multiple images at once at a larger size without switching to another application. I'd suggest 512px or even 1024px. I think this would have minimal impact on users who don't care about this feature (the only thing I can think of is that it would increase the granularity of the icon size slider in the status bar) but would be quite helpful for others. I'm not sure if this is related to any HiDPI issues, but the interface is otherwise scaled normally for me. Regardless, even if some upcoming HiDPI changes increased the preview size, I imagine plenty of users would want still larger sizes.
(In reply to Toby Fox from comment #0) > Currently the max thumbnail size is 256px. My screen's resolution is > 3840x2160, so the largest I can get is approx 5 rows x 8 columns. For a > folder of images, sometimes I want to preview multiple images at once at a > larger size without switching to another application. > > I'd suggest 512px or even 1024px. I think this would have minimal impact on > users who don't care about this feature (the only thing I can think of is > that it would increase the granularity of the icon size slider in the status > bar) but would be quite helpful for others. > > I'm not sure if this is related to any HiDPI issues, but the interface is > otherwise scaled normally for me. Regardless, even if some upcoming HiDPI > changes increased the preview size, I imagine plenty of users would want > still larger sizes. Same kind of from the KDE Forums: Dolphin feature request; Flexible thumbnail size - https://forum.kde.org/viewtopic.php?f=223&t=122874 Short: The KDE/Dolphin is following the https://specifications.freedesktop.org/thumbnail-spec/thumbnail-spec-latest.html -> 5.3. Thumbnail Size: https://specifications.freedesktop.org/thumbnail-spec/thumbnail-spec-latest.html#THUMBSIZE The other sizes are scaled from the 128x128 or 256x256. The thumbnails are made by the kio: https://api.kde.org/frameworks/kio/html/classThumbCreator.html
Do you have screen scaling enabled? If you set it to 2x scaling, the "256px" should actually become 512. (The thumbnails themselves don't support that, though, so they'd be larger but blurry. Fixing that would require serious re-engineering in the thumbnailer)
Created attachment 109740 [details] Screenshot showing 2x scaled display settings and 256px dolphin thumbnails (In reply to Kai Uwe Broulik from comment #2) > Do you have screen scaling enabled? If you set it to 2x scaling, the "256px" > should actually become 512. (The thumbnails themselves don't support that, > though, so they'd be larger but blurry. Fixing that would require serious > re-engineering in the thumbnailer) Interesting - my screen scaling is set to 2x, and thumbnail size maxed out, but it does seem like they're still 256px. See attached screenshot - there are 5 rows, and even without padding or dolphin UI, that would be 5*512px = 2560px, greater than my vertical resolution of 2160px. And the dolphin UI (and all UI elements in my desktop environment) are appropriately scaled - if scaled larger they'd be too big. I understand, however, especially from Rog131's helpful reply, how deep this functionality runs and how dependent it is on other standards and packages, so I see it would be a laborious change. But I do think that as resolutions get ever bigger and devices more multi-purpose and media-heavy, such a change to the whole ecosystem is (hopefully) due eventually. But I imagine this is isn't in the hands of the Dolphin team or even KDE. It's a bummer though. I've tried Gwenview, DigiKam, and several other pieces of software, and so far nothing has this relatively basic (from a user's perspective) functionality :(
In digiKam you can activate in the settings the support of thumbnails with 512x512 pixels. Default is 256x256 pixels maximum. Maik
I cannot reproduce. Setting scaling to 2x, after a relogin I get much larger thumbnails than in your screenshot when setting the thumbnail slider to the maximum value. In fact, for a setting of 256px they are 700 to 750px wide (depending on the image), which seems strange. However, I suspect you simply forgot to relogin, because your screenshot shows a large font size with small icons everywhere in Dolphin, which is a typical symptom in this case. Could you try to relogin and report back? That said, there are still issues with Dolphin's thumbnails in HiDPI mode: - shadow and selection button overlay on previews pixelated - folders with thumbnail preview pixelated - thumbnail pixmaps itself not pixelated, but not looking good because of capped maximum thumbnail size - mismatch between reported size in size slider tooltip and actual size on screen (And even when not in HiDPI mode, someone might want to have a larger thumbnail size.) @broulik: Would it be worth pursuing a change of the FDO spec? If so, how to best approach that? See also: https://phabricator.kde.org/D9078 https://phabricator.kde.org/D6083
IMHO a change to the FDO spec would indeed be worthwhile. 256px isn't really that big anymore on today's displays. Toby, can you re-log-in/reboot and see if that fixes things for you?
Created attachment 109998 [details] Dolphin thumbnails correctly scaled 2x on 3840x2160 display (In reply to Nate Graham from comment #6) > IMHO a change to the FDO spec would indeed be worthwhile. 256px isn't really > that big anymore on today's displays. > > Toby, can you re-log-in/reboot and see if that fixes things for you? Ok, this is interesting! In my previous screenshot, I pulled up the display settings but didn't change them: I had it set at 2x scale for many months. However, I tried changing scaling to 3x, rebooted, changed scaling back to 2x and rebooted again, and now my thumbnails are showing larger as intended - 512px at max. Looks like previously the plasma UI and most applications were correctly scaled for me at 2x, but some applications (dolphin, konsole, maybe others) were stuck at 1x and needed settings to be changed and rebooted to get it to work. Maybe there was some HiDPI-related Dolphin or KDE update a while back that didn't apply properly without this. Anyway, screenshot attached of the it "correctly" scaled at 2x. Now of course the issue is we have a 256px thumbnail upscaled to 512px, so it looks blurry, and the other issues mentioned by Henrik. Situation is a little better, but I definitely think it's worth pursuing further.
At this point, it might be useful to close the original bug and file new, focused ones for the remaining issues. Could you do that, Toby?
What is the status of this ticket? Could someone clarify which information is needed, if any?
I guess Nate wanted Toby to file a new bug and therefore set it to NEEDSINFO, but as that's not done I think we can just keep this bug open. Nevertheless, thanks for the reminder ;) Not much progress on the issues itself, so far.
Seems the original issue regarding HiDPI is fixed and was a local configuration issue. Because of the embedded request for a 512px icon size option, I'm marking this a duplicate of Bug 368954, which requests the same thing, but it's older and the request is clearer in there. Toby, if you have any further issues, please file new bugs to track them individually. See https://community.kde.org/Get_Involved/Bug_Reporting#One_issue_per_bug_report *** This bug has been marked as a duplicate of bug 368954 ***