Currently the texture layers only support .png files. The video layer is no longer supported and it will soon be removed from the Animation Editor. The video layer used to accept .mp4 files but the feature is no longer supported and will not play video files now. The video layer was designed to use a video as a reference when creating animations with Jibo and did not embed videos on Jibo's screen.
If you are interested in seeing other file types supported in the texture layer, I would recommend posting to the Features section (https://discuss.jibo.com/c/jibo-sdk/features) which our team regularly monitors. If you could provide a little detail on what you think some use cases might be for .gif as a texture that will allow our team to take that into consideration when planning future updates to the SDK.