|Applies to:||, ,|
|Definition:||Link to a index page with an image and copyright status for same.|
|Rendered as:||Typically shown in a popup|
| +/- image=
Link to a index page with an image and copyright status for same.
The content of this tag is the web address related to a verifiable image of the mapped feature. The image must have an automatically verifiable licence. Certain display agents will parse the licence information prior to displaying or extracting the image.
Where to Host Images
Images are not hosted directly in OpenStreetMap. Be aware that many image hosting services, especially the free ones, discourage image linking regardless of copyright status. Free accounts may disappear over the long term and paid accounts probably won't outlast the owner.
Images hosted on Wikimedia Commons are often a good stable choice. Here you'll want to link to the index page (e.g. "http://commons.wikimedia.org/wiki/File:Eyjafjallaj%C3%B6kull.jpeg", not the actual image). Similarly for images on sites like Flickr give the top level page for the image, not a link to the actual image. Linking to the index page allows software agents to verify the licence prior to display.
Images are tricky and subject to abuse. In general as a map representing the world, the only acceptable images represent the object on the map. Daylight photographs from the position of a nearby observer are ideal. Provision of commercial images and all forms of self-promotion or advancement of particular agendas are discouraged.
Software that displays images should check the copyright status, and ignore images without a readily discernible and compatible licence.
Variations and Problems
- Shortcut format image=File:image.jpg specifies an image on WikiMedia Commons.
- Ideally the image itself (not the index page) would specify the copyright status of the image. Unfortunately the Exif.Image.Copyright field present in many images is a free form field, and there is no reliable way to parse the content to determine the true image licence.
- This image tag solution will not scale well. For example a particular feature may have multiple valid photos from a variety of vantage points. However should a future open source image exploring application emerge, the image tag data will be available to it, and the community could transition.