Rolling your own serverless OCR in 40 lines of code

[eapriv]

Not sure what “your own” in the title is supposed to mean if you are running a model that you didn’t train using a framework that you didn’t write on a server that you don’t own.

[ddevnyc]

I think in this case "your own" means under your control, rather than a service or license you pay for. "your own" as in ownership of artefacts, not as in being the creator.

[RupertSalt]

Consider the source of the idiom: rolling your own cigarettes.

Which involves taking some rolling papers, a pouch of loose tobacco (or whatever), and perhaps a little device if you're rich. As opposed to manufactured cigarettes, you're just doing some manual assembly for the end-product.

You don't need to cultivate the plants or pulp any trees to roll your own.

[ckrapu]

I originally tried to do this on my own server but my GPU is too old :(

[jen20]

It means "one that is yours" in the same way "running your own plex server" does not imply starting with building a silicon fab.

[self_awareness]

<insert a random "i made this" meme>

[croes]

And then call it serverless

[nkmnz]

Not sure what "baking your own bread" means if you are using wheat grown by someone else in an oven that you didn't build that is run with electricity you didn't created from your muscles' force. You haven't even contributed to the nuclear fusion which created the oxygen for the water molecules you've been using! How dare you, standing of the shoulders of giants!

[voidUpdate]

Wouldn't "Serverless OCR" mean something like running tesseract locally on your computer, rather than creating an AI framework and running it on a server?

[cachius]

Serverless means spinning compute resources up on demand in the cloud vs. running a server permanently.

[normie3000]

Thanks for noting this - for a moment I was excited.

[esafak]

No, that would be "Running OCR locally..."

'Serverless' has become a term of art: https://en.wikipedia.org/wiki/Serverless_computing

[spockz]

Running it locally would typically be called “client(-)side”.

But this caught me for a bit as well. :-)

[mindslight]

Yep. That fraudulent term finally got me this time. Totally serverless except for that remote 3rd party server. Sigh.

[kbyatnal]

Deepseek OCR is no longer state of the art. There are much better open source OCR models available now.

ocrarena.ai maintains a leaderboard, and a number of other open source options like dots [1] or olmOCR [2] rank higher.

[1] https://www.ocrarena.ai/compare/dots-ocr/deepseek-ocr

[2] https://www.ocrarena.ai/compare/olmocr-2/deepseek-ocr

[ckrapu]

I wasn't aware of dots when I wrote the blog post. This is really good to know!! I would like to try again with some newer models.

[segmondy]

you are comparing to DeepSeek's old OCR, there's DeepSeek-OCR2 which btw is amazing from my experimentations. https://huggingface.co/deepseek-ai/DeepSeek-OCR-2

[tclancy]

The article mentions choosing the model for its ability to parse math well.

[vovavili]

A bit surprised to learn that Rednote maintains one of the leading open-source OCR models on the market, nice.

[grimgrin]

hi. i run "ocr" with dmenu on linux, that triggers maim where i make a visual selection. a push notification shows the body (nice indicator of a whiff), but also it's on my clipboard

  #!/usr/bin/env bash

  # requires: tesseract-ocr imagemagick maim xsel

  IMG=$(mktemp)
  trap "rm $IMG*" EXIT

  # --nodrag means click 2x
  maim -s --nodrag --quality=10 $IMG.png

  # should increase detection rate
  mogrify -modulate 100,0 -resize 400% $IMG.png

  tesseract $IMG.png $IMG &>/dev/null
  cat $IMG.txt | xsel -bi
  notify-send "Text copied" "$(cat $IMG.txt)"

  exit

[brainless]

I am working on a client project, originally built using Google Vision APIs, and then I realized Tesseract is so good. Like really good. Also, if PDF text is available, then pdftotext tools are awesome.

My client's usecase was specific to scanning medical reports but since there are thousands of labs in India which have slightly different formats, I built an LLM agent which works only after the pdf/image to text process - to double check the medical terminology. That too, only if our code cannot already process each text line through simple string/regex matches.

There are perhaps extremely efficient tools to do many of the work where we throw the problem at LLMs.

[coolness]

Slight tangent: i was wondering why DeepSeek would develop something like this. In the linked paper it says

> In production, DeepSeek-OCR can generate training data for LLMs/VLMs at a scale of 200k+ pages per day (a single A100-40G).

That... doesn't sound legal

[Zababa]

HathiTrust (https://en.wikipedia.org/wiki/HathiTrust) has 6.7 millions of volumes in the public domain, in PDF from what I understand. That would be around a billion pages, if we consider a volume is ~200 pages. 5000 days to go through that with an A100-40G at 200k pages a day. That is one way to interpret what they say as being legal. I don't have any information on what happens at DeepSeek so I can't say if it's true or not.

[Bishonen88]

Tried adding a receipt itemization feature into an app using OpenAI. It does 95% right but the remaining 5% are a mess. Mostly it mixes prices between items (Olive oil 0.99 while Banana 7.99). Is there some lightweight open source lib that can do this better?

[lkm0]

So I'm trying to OCR 1000s of pages of old french dictionaries from the 1700s, has anything popped up that doesn't cost an arm and a leg, and works pretty decently?

[ks2048]

Take a look at Mistral, https://mistral.ai/news/mistral-ocr-3

[grumbel]

I use Gemini for that. Split the PDF into 50 page chunks, throw it into aistudio and ask it to convert it. A couple of 1000 pages can be done with the free tier.

[speedgoose]

Qwen3 VL.

[ddtaylor]

How does this compare to Tesserect?

[newzino]

Different tools for different jobs. Tesseract is free, runs on CPU, and handles clean printed text well. For standard documents with simple layouts, it's hard to beat.

Where it falls apart is complex pages. Multi-column layouts, tables, equations, handwriting. Tesseract works line-by-line with no understanding of page structure, so a two-column paper gets garbled into interleaved text. VLM-based models like DeepSeek treat the page as an image and infer structure visually, which handles those cases much better.

For this specific use case (stats textbook with heavy math), Tesseract would really struggle with the equations. LaTeX-rendered math has unusual character spacing and stacked symbols that confuse traditional OCR engines. The author chose DeepSeek specifically because it outputs markdown with math notation intact.

The tradeoff is cost and infrastructure. Tesseract runs on your laptop for free. The author spent $2 on A100 GPU time for 600 pages. For a one-off textbook that's nothing, but at scale the difference between "free on CPU" and "$0.003/page on GPU" matters. Worth noting that newer alternatives like dots and olmOCR (mentioned upthread by kbyatnal) are also worth comparing if accuracy on complex layouts is the priority.

[apwheele]

Question for the crowd -- with autoscaling, when a new pod is created it will still download the model right from huggingface?

I like to push everything into the image as much as I can. So in the image modal, I would run a command to trigger downloading the model. Then in the app just point to the locally downloaded model. So bigger image, but do not need to redownload on start up.

[bovinejoni]

That book is freely available from its author in pdf format already… but I guess it’s about the journey?

[velcrovan]

If I had to guess, I would say that this method might be applicable to other books besides the one featured in the post.

[ckrapu]

I wanted to let an LLM be able to grep and read through it.

[sails]

Always wondered how auth validation works on these. Could I use your serverless ocr?

[jbs789]

Why "rolling"? Is this a reference to baking or what's the origin?

[smw]

reference to cigarettes

[fzysingularity]

The cold-boot time on this model can hardly be called “serverless”

[StackTopherFlow]

The real question is why pick python 3.11

[PlatoIsADisease]

Uh... So I've been telling AI to write a single page html/js OCR app. And I'll include the pdf I want as an attachment.

I have 4 of these now, some are better than others. But all worked great.

[zeroq]

tl'dr version:

  step 1 draw a circle
  step 2 import the rest of the owl