Chroma Resampler Issue

Hello,

I am trying to implement a 444 to 422 converter using the Altera VIP Chroma Resampler. I am not using Qsys or SOPCs. I present the input according to the documentation but I do not get any output. I have attached the signaltap trace.

I tried it with 11.1sp2 and 12.0sp1 - timing is met.

Any ideas?

Thank you.