Apple ProIO vout ARGB imdc

Apple ProIO vout ARGB imdc - I looked in the info window of Quicktime at some clips somebody gave me and it said for "Format" None,720x486 (648 x 486), Millions.

In the properties window it listed this "Apple ProIO vout ARGB imdc" for the video codec.

Where does this codec come from ? Is it in the FCP export list, is it proprietary to some piece of hardware and why would the info window say "none".
Never seen this.