DM8168,use VIP module to capture HD video data

I want to use DM8168 Video Input Parser (VIP) Module(YUV 422 8bit embedded sync mode )to capture HD video data.
Because HD is BT1120 16-bit standard,I have to use FPGA to convert the data format to BT656.

Is there such a format for 16bit BT1120 convert to 8bit YC_MUXED BT656.?

Expecting for answer,thank you