Imager ships with five test pictures and a video. Two (parrots and boats) come from the [Kodak set](http://r0k.us/graphics/kodak/). Another (birds) is a sketch of birds by Leonardo, from Wikimedia. The "coins" image comes from scikit-image. The Hubble Deep field (hubble) is from Wikimedia.
The test video ("tennis") comes from [xiph.org](https://media.xiph.org/video/derf/)'s collection.