Zwabel’s Weblog

April 9, 2009

Nicer Direcory Thumbnails, and Thumbnail Sequences

Filed under: KDE — zwabel @ 8:41 pm

When I did my last blog post, there were some comments that said that the folder previews didn’t look as nice as they could. I agree, luckily, one day later Fredrik Höglund came up with a patch to do some more complex and nicer painting on the items. Now the previews are layed out like a bunch of physical photos, with some random rotations, a white border, and drop shadows:

In my opinion, this looks very nice. The fact that the items are rotated randomly takes away some of the regularity that tends to be annoying, and the borders and shadows make it look like “real” objects.

I had some more ideas how the folder-previews, and previews in general, could be made even more useful.

Typically the problem with automatically generated previews for “sequence items”(Like folders, videos, etc., as opposed to simple images) is that you can never be sure that you pick a part of the sequence that is really useful to describe the content.

For example a video thumbnail taken right at the beginning of a movie, will most probably just show an empty black surface. A folder preview may show pictures that are not useful for describing the folder content. Now on several places on the internet, they have found a simple solution: When moving the cursor over the item, jump through different thumbnails from alternative locations in the sequence, to get a better description of the item.

This seems very reasonable, since the probability that one of the sequence items shows something “interesting” is a lot higher than it is for the part chosen automatically for the initial thumbnail, so I’ve spent some of the evenings this week bringing this functionality to KDE.

When an file/directory is hovered, the sequence of thumbnails generated for that item is alternated, showing another thumbnail every second, using a fast fade animation that is friendly to the eye. Currently the only thumb-creator that supports this feature is the one that creates thumbnails for directories, but once there is thumbnailers for videos again, I hope the developers will also implement the interface to support this feature. Since I’m too lazy to do a screencast, I will just attach another screenshot:
Actually all you can see here, is that the icon under the cursor shows different preview pictures than the unhovered version above. You get the Idea.


  1. now expect getting reports like

    Comment by Nick — April 9, 2009 @ 9:07 pm

  2. Awesome!! Thanks.

    Comment by marcin — April 9, 2009 @ 9:18 pm

  3. What about add settings for this thumbnails? (Turn on / off; number of thumbnail 1-4; shape)

    Comment by marcin — April 9, 2009 @ 9:20 pm

  4. >> What about add settings for this thumbnails?

    Please don’t. Let’s not end up with another KDE3.

    Looks great, nice work!

    Comment by Leo S — April 9, 2009 @ 9:30 pm

  5. This looks fantastic! I agree with marcin – the more configurability the better!

    Comment by Arnold — April 9, 2009 @ 9:46 pm

  6. It’s so much better …. I love it 😉

    Comment by val-gaav — April 9, 2009 @ 9:54 pm

  7. Yeah, it’s me again, and I came to say that Vista’s still better!111

    ok, ok, I’m joking. Now it’s much prettier, and I like the hover thing.

    And I have a question/suggestion (sorry I don’t have access to a trunk build right now). What happens if the folder is smaller? Does it show 4 previews too? If yes, aren’t they too small? I think that makes sense to decrease the number of previews if the folders are smaller

    Congratz to all involved

    Comment by Firmo — April 9, 2009 @ 10:06 pm

  8. I want a setting please please please, i have to say i hate how this looks.

    Comment by Albert Astals Cid — April 9, 2009 @ 10:07 pm

  9. Cool!

    Comment by Markus — April 9, 2009 @ 10:19 pm

  10. No offense intended, but randomly rotating previews don’t really hit it for me. I hope there will be a setting to make it regular. It might be “boring”, but the picture previews are already small enough as it is, why distort them further?

    With regard to video previews for files, not directories, are there any plans for live-previews? This would IMHO be really cool. Of course, this should only be done when hovering over an icon.

    Comment by Jean Azzopardi — April 9, 2009 @ 10:32 pm

  11. Will the “random” rotations be the same each time the user views the directory? I think they should be, so that one can visually recognize a particular directory. One way to accomplish that would be to use a hash of the directory name as the random seed.

    Comment by Martin — April 9, 2009 @ 10:57 pm

  12. Hi! Just a thought… I like the ramdom rotation thing, however, in such a small size, the edges look ugly (at least in the screenshot).. I was wondering the necessity of having 4 previews _and_ the scrolling feature.. I guess that the 4 previews idea is to lower the probability of choosing some meaningless preview. However, if you add the scroll feature you can have just 1, bigger preview. In this way, it the chosen photo does not tell the user what the contents, he will hover and scroll through the contents.

    The one preview plus scroll allows for a bigger preview (easier to identify) of a photo, better looking (IMHO) and if it is a lame choice of preview, the use can very easily change it. Maybe, the scroll feature can remember the photo where the user “ended the scroll” and use that one from them on to preview the folder.

    Great work!!

    Comment by Lucas — April 9, 2009 @ 10:59 pm

  13. @Martin: Yes I had exactly the same idea, and thus I’ve implemented it using exactly that random seed. 🙂

    @Lucas: Maybe the edges can be made look a bit nicer at that size. The good thing about always showing multiple items is that it will help you to recognize that the directory contains multiple items, and clearly sets it apart from for example image thumbnails. The iterating over the items happens automatically if the user hovers it, so it’s probably better to make that not persistent, else the directories will look differently after every single hovering. Now, since the random rotations are always the same, and the initial shown images are always the same, the directories are very easy to recognize.

    It would probably make sense to reduce the preview-count to 2 for very small sizes.

    Comment by zwabel — April 9, 2009 @ 11:09 pm

  14. About configurability: It will at least be possible to disable previews for directories altogether(Peter Penz is working on that). About enabling/disabling the rotation of the items: Where should such an option go in the options menu? Feels like over-configurability. Maybe we can make the themes set some flags so the themes decide whether rotation should happen or not.

    Comment by zwabel — April 9, 2009 @ 11:13 pm

  15. F#ck yeah! This is beyond awesome! Can’t wait for 4.3!

    Comment by shiny — April 9, 2009 @ 11:49 pm

  16. @preview sizes: Maybe multiple big previews stacked. Like “Flip Switch” of kwin… (

    Comment by nik — April 10, 2009 @ 12:23 am

  17. This really confirms what I’ve always been thinking – that the dolphin parts icons really need to make better use of its space. Just have a look at the screenshots above, there’s about 75% of a whole icon of space between every icon. If only this space was used better, this kind of icon preview would also look much better, and allow the user to make the icons really big to get a good overview (because the small previews get bigger) of the pictures in the folder.

    Comment by Harald — April 10, 2009 @ 12:26 am

  18. Much better!

    Only I littel thing left, but no so easy to add…

    When a folder use a different icon (desktop, developpment, download and everything in the filesystem icon folder is used, it is replaced. The best would be to display the icon over the preview, but I don’t think it is possible. So, the onyl way it can be done is to allow an icon to go over the regular folder and over the previews. It can be added quite easily, but there is another problem. Isn’t this thing part of a freedesktop specification? Will it broke it? I think that gnoem actually do it that way (2 layers). So, is it possible to add it?

    Comment by Emmanuel Lepage Vallée — April 10, 2009 @ 1:00 am

  19. Oh for flying spaghetti monster sake! just stack em’ please!

    Comment by veins — April 10, 2009 @ 2:26 am

  20. You’re da master! This is so cool… When I updated yesterday and saw the new look, I spend 10 minutes looking at different folders 😉

    Generally the pics look pretty good, sad that it takes a while to generate them 😀

    About configurability, it’d be good if one could turn it off, but I wouldn’t add more clutter to the configuration.

    Lovely work, thank you!

    Comment by jospoortvliet — April 10, 2009 @ 6:10 am

  21. Totally awesome 🙂 and KDE shows proves to have a unique style 🙂

    Comment by Diederik van der Boor — April 10, 2009 @ 6:43 am

  22. About the video preview, I’d love to have something like this : the thumbnails for a video should contains several frames, each snapshot could be one .png or maybe all the snapshots could be embedded in a multi-frame format (like MNG or something ?) so we have one file that contains all the thumbnails for a video. This .mng could be stored at the same place as the regular pic preview.

    When Dolphin or Konq request a preview for a video, it can pick some of the snapshots embedded in this file and construct a grid, a film-like pic or why not play the frame like an animated GIF. With that, the browser can determine how many frame it should show (just 4 frames when one hover over the file, or a full sheets when the user request a full preview. Morehover, this pictures containing snapshots of videos could be used in Kaffeine or Dragon player to give a nice preview of a video. One could even imagine that, when playing a video, the user could show all the thumbnails for this video and click on one of them to quickly seek here in the video (the timestamp should be somehow embedded in the pic of course)

    what do you think ?

    Comment by DanaKil — April 10, 2009 @ 7:32 am

  23. What about the speed of thumbnails generation? IMHO this is one of the most annoying issues in current Dolphin. Is someone working on that? Can you take some parts of code from Gwenview’s thumbnailer? That is blazingly fast!

    Comment by baxeico — April 10, 2009 @ 8:24 am

  24. Very nice work!

    What visually bothers me the most about it now is actually the very square and regular blue “folder” in the background. How about doing away with this altogether and just making it a “pile” of photos ( perhaps with the folder as a small emblem in a corner? )

    – Nikolaj

    Comment by Nikolaj Hald Nielsen — April 10, 2009 @ 8:44 am

  25. Congrats! That’s really awesome, thank you for considering the comments.

    The rotation should really be configurable, I (and others) find it pretty annoying, while others love it, so an option is really needed.

    Comment by blueget — April 10, 2009 @ 9:01 am

  26. @baxeico: Since KDE 4.2 the thumbnail generation of JPEG images is done equally fast as in Gwenview.

    Comment by Peter Penz — April 10, 2009 @ 9:33 am

  27. I don’t like the rotations, but I like the borders.

    Comment by UA=42 — April 10, 2009 @ 12:55 pm

  28. Looks really good. Have you seen my Brainstorm idea about folder thumbnails? It has a different appearance as well as a way to handle the case where the folder is empty (so you know whether the file is really empty or just has previews turned off):

    Comment by TheBlackCat — April 10, 2009 @ 1:13 pm

  29. > Please don’t. Let’s not end up with another KDE3.

    oh no, idiots in the thread.

    Comment by dmitriy — April 10, 2009 @ 2:58 pm

  30. I have to say that I really don’t like it as it is now. The folder in the background of the thumbnails doesn’t make any sense. It like if the photos were floating outside the folder. Also, the photos don’t respect the inclination in the folder.
    I think that insted of adding rotaions, frames, etc. You should try to get the photos preview INSIDE the folder.

    Thanks for the good work.

    Comment by Gonza — April 10, 2009 @ 3:24 pm

  31. @ Gonza: You mean like this:

    Comment by TheBlackCat — April 10, 2009 @ 3:44 pm

  32. Hey, congratulations on your successful blog. I started a wordpress blog recently so hopefully you’ll have some time to check it out! Keep up the good work.

    Comment by ChicagoismynewBlog — April 10, 2009 @ 3:59 pm

  33. I like the “pile” of photos idea. KDE is about pushing barriers. But what icon would you show with an empty pictures directory? The change from a pile of photos to a folder might confuse people and they would wonder where their directory went.

    Comment by wvmac — April 10, 2009 @ 4:15 pm

  34. Awesome work, kudos!

    Comment by plop — April 10, 2009 @ 8:36 pm

  35. […] Nicer Direcory Thumbnails, and Thumbnail Sequences When I did my last blog post, there were some comments that said that the folder previews didn’t look as nice as they could. I agree, luckily, one day later Fredrik Höglund came up with a patch to do some more complex and nicer painting on the items. Now the previews are layed out like a bunch of physical photos, with some random rotations, a white border, and drop shadows… […]

    Pingback by Links 10/04/2009: KDE 4.3 Preview; Mozilla Labs Output | Boycott Novell — April 10, 2009 @ 9:57 pm

  36. […] Nicer Direcory Thumbnails, and Thumbnail Sequences When I did my last blog post, there were some comments that said that the folder previews didn’t look as nice as […] […]

    Pingback by Top Posts « — April 11, 2009 @ 12:40 am

  37. @TheBlackCat: Yes, something alike but prettier.

    Comment by Gonza — April 11, 2009 @ 7:16 pm

  38. To all the “oh please give the option to modify the rotation factor, shadow, borders, hue saturation, blurriness, pixel indentation etc etc”, you have to understand that you are a minority which does not deserve an option exposed in the UI. The only option exposed should be “use preview for directory” (which is already provided AFAIK). The rest could be configurable as well but should be only present as an hidden option (so, an item in the conf file).

    Anyway geat work, really, I love it!
    Another idea (for 4.4) could be that the pictures when the directory is hovered could grow bigger out of the folder icon… I mean some kind of zoom but only for pictures, everything nicely animated. Is this technically possible?

    Comment by Vide — April 13, 2009 @ 10:21 am

  39. @Gonza – I see your point but does it really have to “make sense”. I mean the if you really look at it a set of folders standing there on there own on a white background that you can move about with a scrollbar isn’t exactly _physically correct_. It looks pretty and shows previews and makes the folders recognisable, so it’s doing a great job.

    Comment by maninalift — April 13, 2009 @ 2:24 pm

  40. […] К слову, пока мы писали эту заметку, разработчики улучшили эту фичу, и теперь папки с эскизами картинок выглядят вот […]

    Pingback by KDE для художников « — April 14, 2009 @ 11:23 am

  41. i have been using the “randomly rotating previews” and it is starting to get on my nerves.

    I have a folder with a bunch of video files in it and atleast one of the file thumbnail will change its icon when i move the mouse across the folder. I just tested this right now. I just moved the mouse slowly randomly across the folder and random files started changing their images.

    I like to anticipate what my computer next with each of my actions. This rotation of images on hovering is having a behavior i cant predict and its anooying.

    Now i am almost afraid to hover around my video files because i have no idea what file will change its image and what will not and this is annoying more than anything else.

    I hope the time it takes for the mouse to be over the file will be increased to reduce the likeliness of the above

    Comment by mtz — April 16, 2009 @ 2:31 am

  42. Do you know what would be totally rad? – if you had just a ‘stack’ (with perspective) of the images/documents previewed without the folder icon altogether and then when you click on it, it would animate all the documents fading in while the already previewed ones slide into place.

    Comment by Socceroos — April 20, 2009 @ 5:58 am

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