What type of filter is this?

[wparrish24]

Around the 3:05 minutes into this video, they show this artist on the rooftop. Behind him are lights that are blurred out in a perfect circle, however he is in focus. Is this a special effect filter, what type?

http://www.grindstar.tv/video/1179/Juvenile-Gotta-Get-It

 

[wparrish24]

Bokeh circles

They are bokeh circles

 

[Graeme]

That is caused by having a system with a shallow DOF, either a HDSLR or a regular camcorder with a 35mm adapter will give you this effect.

 

[grinner]

I didn't see a filter. Just depth of field from the lens.
You can easily create it though with a blurred layer and an animated mask.