Animated image format on Pixiv using HTML5 canvases for high quality, cross-browser animation. Includes individual frame lengths and a pause feature. Ugoira are stored as a Zip file containing each frame, with the frame delays stored separately.
Danbooru natively supports uploading ugoira and playing them back with Pixiv's own open source player as of October 27th, 2014. Danbooru also adds a seek slider to the UI.
In order to upload a native ugoira to Danbooru you must do a source upload. Uploading a file from your computer will not work. You can do this either by using the official upload bookmarklet or pasting the Pixiv source into the source field on the upload page.
There are two methods for downloading an ugoira on Danbooru to your computer:
- If you want the original files, you can download the unmodified Zip file containing them. You may also need the frame delays - these are accessible via Danbooru's post API.
- The second method Danbooru provides is a converted WebM version of the ugoira, accessible via the "Save as video (right click and save)" link underneath it. This WebM conversion is more portable and can be played on regular video players, and it tends to have smaller file size than the ugoira itself, but is not lossless in quality.
Before native ugoira support was added to Danbooru, users uploaded these by converting them to some other animation format that was supported, such as animated GIF, WebM, or animated PNG. If you come across one of these older converted posts and feel that it is deserving enough, upload the ugoira natively as described above and make it the parent of the converted version.