Background video on tablet/phone? Or still image?

As I understand videos won't auto play on tablets/phones to prevent user from using unwanted data. At the same time there's a trend on using videos full window backgrounds. I was wondering what's recommended to do on mobile sites?

1. Remove the video and replace it with an image?
2. Load a still image and give the user an option to play the video?
3. Load the video (paused) and give the user an option to play the video?
4. Maybe use an animated imaged?

Please keep in mind that background videos are not the main focus of the website. So these videos are more about aesthetics then usability.