What's the proper way to preprocess on Triton with streaming?

I have a car flow video that need to detect license plate.
Client decode video by OpenCV and send raw BGR data to Triton.
I’ve write a simple preprocessing on Triton with OpenCV(Resize and Normalize).
This way works but can’t handle batched data.
I know the recommand way to preprocess data on Triton is by DALI.
But DALI seems to work only on coded Images not decoded Images.
What’s the proper way to preprocess On Triton with BGR data?