top | item 44649353

(no title)

freezed8 | 7 months ago

This blog post makes some good points about using vision models for retrieval, but I do want to call out a few problems: 1. The blog conflates indexing/retrieval with document parsing. Document parsing itself is the task of converting a document into a structured text representation, whether it's markdown/JSON (or in the case of extraction, an output that conforms to a schema). It has many uses, one of which is RAG, but many of which are not necessarily RAG related.

ColPali is great for retrieval, but you can't use ColPali (at least natively) for pure document parsing tasks. There's a lot of separate benchmarks for just evaluating doc parsing while the author mostly talks about visual retrieval benchmarks.

2. This whole idea of "You can DIY document parsing by screenshotting a page" is not new at all, lots of people have been talking about it! It's certainly fine as a baseline and does work better than standard OCR in many cases.

a. But from our experience there's still a long-tail of accuracy issues. b. It's missing metadata like confidence scores/bounding boxes etc. out of the box c. Honestly this is underrated, but creating a good screenshotting pipeline itself is non-trivial.

3. In general for retrieval, it's helpful to have both text and image representations. Image tokens are obviously much more powerful. Text tokens are way cheaper to store and let you do things like retrieval entire documents (instead of just chunks) and input that into the LLM.

(disclaimer: I am ceo of llamaindex, and we have worked on both document parsing and retrieval with LlamaCloud, but I hope my point stands in a general sense)

discuss

order

No comments yet.