I have wondered this for a while but have not been able to find sufficient information about it.
Most media on Wikipedia is listed under the Creative Commons license. This means that it's free but must be given attribution when used (credited).
Here is a good example of that: Reykjavík_Old_Harbor
Now, it is very easy to include attribution on a website, on print, etc, as a text credit can be placed above, below, alongside the image, etc.
But what about video? If you create a video for a corporate presentation, a tradeshow, a commercial, etc, how can you attribute this? Do you need to place a watermark throughout the video when the image is displayed, for example?
Any thoughts would be appreciated.