The Preview Gallery is just one part of the app that may need access to data derived from `prepareBlob`. Fir this reason I think that this data should be attached to the image object before the 'newitem'/'newmedia' event is fired from insdie the `CameraController`. 

If the app is firing a `newmedia` event, I'd assume that it would already come with all the meta data, thumbnails and low level properties a view would require to show it. I don't think further image processing/manipulation should be required in controllers like this.