[DOC]: What happens when extract method is none?

[alexliap]

How would you describe the priority of this documentation request

Would be nice

Describe the future/missing documentation

i am trying to use nv-ingest in the rag blueprint and i have come across an issue:
when the extract method is pdfium, there is no problem ingesting pdfs but i can not ingest images
when the extract method is None, i can ingest pdfs and images as well but pdfs which are scanned images fail

so what happens when extract method is None?

Where have you looked?

https://docs.nvidia.com/nemo/retriever/latest/extraction/nv-ingest-python-api/?h=pdf+extract#quick-start-extracting-pdfs