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polishdude20 • yesterday at 8:25 PM • 2 replies • view on HN

How do you extract the content? OCR? Pdf to text then feed into qwen?

I tried something similar where I needed a bunch of tables extracted from the pdf over like 40 pages. It was crazy slow on my MacBook and innacurate

Replies

philipkglass • yesterday at 8:47 PM

If you have a basic ARM MacBook, GLM-OCR is the best single model I have found for OCR with good table extraction/formatting. It's a compact 0.9b parameter model, so it'll run on systems with only 8 GB of RAM.

https://github.com/zai-org/GLM-OCR

Use mlx-vlm for inference:

https://github.com/zai-org/GLM-OCR/blob/main/examples/mlx-de...

Then you can run a single command to process your PDF:

  glmocr parse example.pdf

  Loading images: example.pdf
  Found 1 file(s)
  Starting Pipeline...
  Pipeline started!
  GLM-OCR initialized in self-hosted mode
  Using Pipeline (enable_layout=true)...

  === Parsing: example.pdf (1/1) ===
My test document contains scanned pages from a law textbook. It's two columns of text with a lot of footnotes. It took 60 seconds to process 5 pages on a MBP with M4 Max chip.

After it's done, you'll have a directory output/example/ that contains .md and .json files. The .md file will contain a markdown rendition of the complete document. The .json file will contain individual labeled regions from the document along with their transcriptions. If you get all the JSON objects with

  "label": "table"
from the JSON file, you can get an HTML-formatted table from each "content" section of these objects.

It might still be inaccurate -- I don't know how challenging your original tables are -- but it shouldn't be terribly slow. The tables it produced for me were good.

I have also built more complex work flows that use a mixture of OCR-specialized models and general purpose VLM models like Qwen 3.5, along with software to coordinate and reconcile operations, but GLM-OCR by itself is the best first thing to try locally.

➕ show 1 reply
chrisweekly • yesterday at 9:40 PM

1. Correction: I'd planned to use Qwen-3.5 but ended up using gemma3:4b.

2. The n8n workflow passes a given binary pdf to gemma, which (based on a detailed prompt) analyzes it and produces JSON output.

See https://github.com/LinkedInLearning/build-with-ai-running-lo... if you want more details. :)