We will connect 4 NTSC cameras to the video decoder IC like a below figure.
the video decoder IC merges multi-video streams into a single BT.656 output.

In this case, Channel ID(CH ID) is embedded into EAV/SAV's least significant two bits such as below format.
Can i.MX8X series receive these data via parallel CSI interface?

Best Regards,
Kazuma Sasaki.