[Wikitech-l] Re: Gallery image size defaults

By default in MediaWiki, they are 120 pixel height, 120 pixel width. Boxed 120x120. So neither dimension may exceed 120, but most thumbnails will actually be smaller than that on one of the dimensions. Other wikis often increase the default gallery size. 200x200 would be a I think we should do some user testing on that. Default normal thumbnails are already 220px wide, 200 might be too big, but user testing seems best. There's a 2013 comment in the above Phabricator thread saying that This would still hold true. There is a big difference between 1 wiki deviating and ALL wikis deviating from a standard in terms of capacity (how many differing thumbnails will get generated). Something like Module:Gallery doesn't really register in that regard, as Category and Special:NewFiles galleries are probably generating a ton more thumbnails than any gallery in a wiki page will. There are also performance considerations. If that switch were to happen in one go (essentially not possible, all wiki's would hammer the thumbnailing api) and we would duplicate the file storage required for that 'bracket' of files, which may or may not be possible. A change might have to be made gradually (to avoid ddos the thumbnailer), and once the change has been made likely we have to clean up the old thumbnail sizes as they are not likely to be used any longer. We have done this before, there is probably a maintenance script to cleanup thumbnails of certain sizes somewhere.... The biggest issue might be that the gallery size of 120x120 is also used by the file history table... So unless we want to double the file count for this bracket, we would have to increase that size as well. More generally, what are the sizes of thumbnails already created by The current pre rendered sizes are [ 320, 640, 800, 1280 ]. These are the sizes for the download actions, and sizes used by MultimediaViewer. These pre rendered sizes are pretty arbitrary and some improvements are probably possible there. However it doesn't really matter for this issue. What matters here is to limit the amount of common sizes used and the pre-rendering doesn't actually take into account all common sizes (for reasons). So 1. Figure out a good new size 2. Test the new size 3. Decide if we want to up the size of file history items as well 4. Roughly calculate how many bytes of thumbnails we would have to generate and how much data that would take up. (depending on what to do with file history this should also take into account old versions of files). 5. See if we can handle that increase temporarily and/or permanently. Several points of this likely require involvement of the operations and services (swift data storage and thumbor) teams. We could also introduce a new wgGalleryOptions setting and only update the default for the gallery tag (traditional mode) itself and leave all other thumbnail sizes of special pages, categories, file history etc at their current size. This would likely be easier to deploy, but might be less future proof (people might ask for those to be changed as an immediate followup). DJ On Sat, Jan 6, 2024 at 7:09 PM <Peter.Ingraham(a)gmail.com> wrote: