GNOME Bugzilla – Bug 523883
Thumbnails for 200% zoom are regenerated each time a folder is opened.
Last modified: 2010-04-01 21:32:51 UTC
The bug has been opened on https://bugs.launchpad.net/ubuntu/+source/nautilus/+bug/204434 "Binary package hint: nautilus When I open a folder with images (around 20 wallpaper sizes), and change the zoom level to 200%. It resizes the thumbnail image, so obviously it becomes blurry. Note this process is completed quickly. Then it seems to create a new thumbnail from the original image with the larger thumbnail dimensions, providing sharper and aesthetically pleasing thumbnails. This process is slow but understandable. If I close Nautilus and open the same folder (it remembers the zoom level), it's using the smaller thumbnails, than the larger sharper ones it created earlier. Then it goes around re-creating the larger thumbnails. Slows the systems down in the process. This it deters you from setting the zoom level up in a folder, it isn't caching/saving thumbnails at a higher zoom. This also occurs if you navigate back and forth to the folder. This only affects the Hardy Alphas. I tried this on Gutsy, it doesn't have a problem as it never tries to get a better thumbnail when you increase the zoom level. When you are testing make sure the images are of wallpaper sizes then you can really see Nautilus upgrading the original thumbnail." It also makes nautilus really slow when browsing those folders again
Just a guess: gfile only provides G_FILE_ATTRIBUTE_THUMBNAIL_PATH for normal size thumbnails. There is no "G_FILE_ATTRIBUTE_LARGE_THUMBNAIL_PATH". http://www.mail-archive.com/nautilus-list@gnome.org/msg04719.html - Mike
*** Bug 531987 has been marked as a duplicate of this bug. ***
may be related to Bug #532725# - and share a fix (?).
*** Bug 553717 has been marked as a duplicate of this bug. ***
*** Bug 539191 has been marked as a duplicate of this bug. ***
Its not actually making thumbnails. For large icons we just read the actual images to use as thumbnails. Since these are not thumbnailed we of course get to re-read them on next visit. I think this is nicer, since without it you'd just look at blurred upscaled thumbnails if you choose a large zoom level. If you don't want this, just don't choose such a large zoom level.
My bug, which was marked as a duplicate of this pointed out that in compact view 400% the thumbnails get regenerated every time.. but in compact view the thumb size is 100x100.. thumbsizes are 128x128, 256x256.. so this is clearly a bug.
christoph: Yeah, that seems like a bug. Maybe we're requesting too large a thumbnail in the compact view (and then scaling it down).
Testing this a bit, I think we're a bit overzealous at using the higher quality thumbnail. i.e. at 150% we're using thumbnails at 144 pixels. Its probably ok to scale these up, as its pretty close to 128. Maybe we should limit it at 128 + 25% == 160 pixels.
Created attachment 130573 [details] [review] Force thumbnail size for compact view, only load original for thumbnail if scaling up more than 25%.
2009-03-16 Alexander Larsson <alexl@redhat.com> Bug 523883 – Thumbnails for 200% zoom are regenerated each time a folder is opened. * libnautilus-private/nautilus-file.c: (nautilus_file_get_icon): allow scaling up thumbnails, use the scaled up thumnail for up to 25% size increase. * src/file-manager/fm-icon-container.c: (fm_icon_container_get_icon_images): Force thumbnail size for compact view to avoid loading at wrong size and then rescaling