I can't help feeling the bird looks stressed rather than playful to me, and even if not an irritated cat could easily hurt the bird swatting it away. I might be over cautious but I wouldn't let this play out between my own bird and cat - makes me really nervous.
Looks to me like that bird want in on that cats food, and the cat is in the way. Very funny video. I think I was more afraid for the cat then I was for the bird.
I hadn't thought that they might be wild birds - I guess that's a bit different. I get a lot of bird clips sent to me by friends and family with an 'isn't this cute' header and often I find myself thinking, well no, that's a disaster waiting to happen and the owner's happily filming it instead of stepping in to head it off. It still looks to me as though the bird is stressed and trying to drive off a predator but I wouldn't have an issue with it if the birds are wild.
As a conciliatory gesture, here's a bird vs cat clip where the cat is definitely out of its depth, and a nicely done feline rescue operation:
[ame="https://youtu.be/X1baqLbmqaQ"]The Cats and a Curious Eagle - YouTube[/ame]
Years ago,we had a cat named PITA <I'm sure you can figure out what the letters stood for >,and Smokes house was on the floor..well PITA would prance around Smokes house,with his tail up in the air.
One day he got a little too close,and Smokey was on her roof top. While PITA walked by,with his tail high in the sky,Smokey reached out and grabbed a beakfull of tail hair , PITA took off like a shot out of a gun,and Smokey would yell out to him "DAMN CAT!!!...GO!!!!" I almost pooped myself