When I was creating Zoetrope, I wanted to make it easy for other apps that work with images to take advantage of Zoetrope’s capabilities and create videos from those images. There are two easy ways to do this with Zoetrope: using the file picker contract and using the share contract.
In Zoetrope, pressing the Add photos button opens the file picker which shows images from any apps that supports the file picking contract. One interesting scenario is with SkyDrive – where you can use SkyDrive on the web, Windows, Windows Phone, Mac, or mobile apps (iOS, Android) to capture photos and then use the Zoetrope to create the animation.
The File Sharing contract enables apps to share data and content with other apps in a structured way. Zoetrope acts as both a share target and share source. As a share target, any app that shares images as StorageItems with Zoetrope will open a share pane and allow the immediate creation of a movie from the images. As a share source, Zoetrope will create and share a .mp4 video of the current animation. Decrease the speed to 0.2 FPS and you have an instant a slide show movie from a series of your photos with a 5 second interval! In the screenshot below, the Authentic app is sharing a collection of images from a media package with Zoetrope to create a slide show video of those image: