Help:Gadget-ZoomViewer
 | This is the documentation for ZoomViewer, a JavaScript gadget which can be enabled or disabled in your Preferences. The script itself is located at MediaWiki:Gadget-ZoomViewer.js. |
 | If you need more help, please ask at the discussion page or at Commons:Help desk. Documentation: |
ZoomViewer adds links to zooming image viewer on the toolserver to every image description page of images over 2 megapixels (not megabytes; ZoomViewer multiplies the pixel width times the pixel height). This is particularly useful to look at large images. It downloads multi-resolution data incrementally. This way you don't have to download the entire image, just the stuff you are actually looking at, good for low bandwidth, but also much faster for browsing images. There is a flash and a JavaScript version available.
The ZoomViewer gadget is enabled by default for all users, whether logged in or not. Registered users can disable it by unchecking it in their preferences (Gadgets->Improved navigation).
Some examples:
- Glacier pano 480MP Zoomviewer
- Hong Kong Skyline 94MP Zoomviewer
- Chicago Skyline 117MP Zoomviewer
- Geological Map of Minnesota 250MP Zoomviewer
- NGC 6357 149MP Zoomviewer
- Denver Airport 111MP Zoomviewer
Those examples above have all already been preprocessed. When you try to view an image for the first time it has to be fetched from commons and transformed into a zoomable image. This has to be done only once for each image (the result is then cached). The preprocessing can take up to 2 minutes. A status is displayed along with a little spinner. In some cases (for very large images) a page reload can be necessary. For even larger images the preprocessing program may exceed allowed memory consumption on the toolserver. Those images can be processed manually (leave a note on the discussion page).