How to make a proper Gif animation inside an SVG mask?

Question

gif

Good afternoon.
There is such a svg https://jsfiddle.net/tyr1552f/1/ play button
inside it you need to insert a translucent gif, for example this https://jsfiddle.net/668q6jxe/3/ but as you can see it is not translucent. Can I make it translucent? Or what is the best thing to do?

Answer 1

For those who are interested here is a working version https://codepen.io/anon/pen/zPjELY