Hardware decoding returns null pointers

[FallingSnow]

When I decode via software everything works as expected. But when I switch over to hardware decoding the data buffers are null. Do you need to pass a work surface rather than null to MFXVideoDECODE_DecodeFrameAsync when decoding via hardware?

[FallingSnow]

Found out what I was doing wrong. Initialized a variable to the value (not a pointer) then called the map interface function. The variable kept the old value. This works with SW because there is no need to map the data, but on hardware this is initially null till mapped. Silly mistake.