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OCR for construction documents does not work, we fixed it
So we've built an API and trained models that detects fixtures, extracts schedules, and analyzes construction documents. Check us out!
More examples:
- https://www.getanchorgrid.com/developer/docs/endpoints/drawings-doors https://www.getanchorgrid.com/developer/docs/endpoints/drawi...
Main website:
- https://www.getanchorgrid.com/developer https://www.getanchorgrid.com/developer
Why we did it:
https://www.getanchorgrid.com/developer/docs/changelog/construction-drawings-are-data-prisons https://www.getanchorgrid.com/developer/docs/changelog/const...
- superdocs1 6mo agoInteresting, I've dealt with a similar problem before. If anyone needs a self-hosted/custom solution, feel free to reach out.
- xnx 5mo agoDoesn't Gemini do this directly? I uploaded an image and asked it to identify the doors and it gave me a JSON array of the boxes.
- rmpanga04 5mo agoThis is incredible
- deleted 6mo ago[deleted]
- fithisux 6mo agoOf course it is not working. PDF and images are supposed to be tamper resistant. OCR tries to reverse engineer them.
- kube-system 6mo agoSince when is tamper resistance a part of PDF or any common image format?
- pwagland 6mo agoPDF files can be signed, that is tamper resistance. Tamper resistance doesn't have to make any difference to the readability of the document.
- kube-system 6mo agoSo can any type of file -- that doesn't have any relevance to the supposed design of every file type in existence. Now, later versions of PDF do have explicit support for signatures, but what does this have to do with preventing OCR? OCR reads a file, it doesn't change the original file.
- ranger_danger 6mo agoSome OCR solutions do change the original file, like OCRmyPDF. They take layers that were just images before and replace it with text layers so that you can search the document.
- kube-system 6mo agoThat isn't OCR, but an application of the resulting output of OCR. Again, a signature on a PDF or any type of file doesn't prevent you from reading it. (It also doesn't technically prevent you from changing it, it just enables the detection of changes to a particular file.) There's nothing about PDFs or image formats that prevent anyone from doing OCR. The reason construction documents are difficult to OCR is because OCR models are not well trained for them, and they're very technical documents where small details are significant. It doesn't have anything to do with the file format
- fithisux 6mo agoTrue but you can make modified copies if you reverse engineer it with OCR.
- jimjimjim 6mo ago
- achillesheels 6mo agoLove it! Starbucks Vente Machiato sip Love to give it to an arc client, not sure who the right person to implement this would be? Hmm…
- wcisco17 6mo agoHey OP here - Love to help if you're looking for a team to implement a solution. https://cal.com/anchorgrid/anchorgrid-external-meeting?duration=30&overlayCalendar=true https://cal.com/anchorgrid/anchorgrid-external-meeting?durat...
- Iulioh 6mo agoWhen will this be available for 30000x8000px electrical diagrams? I have to make a BOM and oh boy I hate my job
- jsidney 6mo agoWhat do you hate the most?
- stronglikedan 6mo agosilly questions
- oritron 6mo agoWhat software made the bitmap? Seems like a step earlier in the pipeline could help generate a BOM more easily.
- Iulioh 6mo agoI'm not really sure and I don't have access to it, I just recive flat PDFs or TIFFs A lot of them are "archival" so I'm pretty OOL
- dylan604 6mo agoYou might even be SOL It is telling that so many of the comments here assume the person with a thing that is not the most practical would be easily able to request thing in a different format. The assumption that the person with the inconvenient thing would never have thought to ask if more convenient thing was available and just willfully toiling with the inconvenient thing is kind of insulting.
- oneneptune 6mo agoAlso, in the construction industry you get an updated drawing file a day before the bidding closes... good luck getting the GC to send more detailed files (that they themselves got elsewhere) in that time. You're better off sending it to your estimation department in India and letting them work through the night to put together the new estimations.
- alexeischiopu 6mo agoGood idea :)
- wcisco17 6mo agoThanks!!
- vessenes 6mo agocool. What's pricing like?
- Terr_ 6mo ago> OCR for construction documents does not work I'm reminded of the Xerox JBIG2 bug back in ~2013, where certain scan settings could silently replace numbers inside documents, and bad construction-plans were one of the cases that led to it being discovered. [0] It wasn't overt OCR per se, end-user users weren't intending to convert pixels to characters or vice-versa. [0] https://www.youtube.com/watch?v=c0O6UXrOZJo&t=6m03s https://www.youtube.com/watch?v=c0O6UXrOZJo&t=6m03s
- TehCorwiz 6mo agoIf I recall it was an artifact of the compression algo. Full context and details: https://www.dkriesel.com/en/blog/2013/0802_xerox-workcentres_are_switching_written_numbers_when_scanning https://www.dkriesel.com/en/blog/2013/0802_xerox-workcentres...
- hackcasual 6mo agoJBIG2 does glyph binning, as you say not exactly OCR, but similar. So chunks of the image that look sufficiently similar get replaced with a reference to a single instance.
- thaumasiotes 6mo ago> not exactly OCR, but similar. So chunks of the image that look sufficiently similar get replaced with a reference to a single instance. How can we describe OCR that wouldn't match this definition exactly?
- Dylan16807 6mo agoJbig2 dynamically pulls reference chunks out of the image, which makes it more likely to have insufficient separation between the target shapes. It also gives a false sense of security when it displays dirty pixels that still clearly show a specific digit, since you think you're basically looking at the original.
- thaumasiotes 6mo ago
- testUser1228 6mo agoWhat do you foresee being the end use case for this (or most valuable use case)?
- wcisco17 6mo agoAnyone building in or for construction tech — whether that's a startup building estimating or project management software, a construction company with an internal tech team solving this themselves, or a builder looking to automate their workflow. The common thread is drawings. Every one of those groups lives and dies by their ability to extract actionable data from a PDF that was never designed to be machine-readable. We're building the layer that makes that possible so they don't have to start from scratch.
- wang_li 6mo agoWhy does the workflow lie at the level of a real or virtual piece of paper and not in the metadata from the applications used to create that piece of paper? Seems like a CAD tool would allow you to identify each element of the drawing, assigning metadata as required.
- jsidney 6mo agoOnly a small set of construction stakeholders participate in the CAD ecosystem (e.g., architects, large GCs) while a broader set of stakeholders (subcontractors, trades, smaller GCs/CMs) do not receive BIM files and work with PDFs. CAD/BIM is a wonderful aspiration but for many the reality is PDFs.
- instig007 6mo agoRe. "CAD/BIM", technically speaking CAD doesn't imply BIM, and the industry's promotion of BIM is akin to AI promotion among software engineering teams - the benefits aren't clear upon detailed review of the advertised capabilities. The CAD part, on the other hand, is generally recognized as the essential tooling for the profession and I'm surprised to hear that it just is a "wonderful aspiration".
- hspraggins77 6mo agoGreat points raised!
- ware-intel 6mo agoYour smart features looks like a game changer? Nice job!
- jsidney 6mo agoThanks!!
- frogguy 6mo agoLooks cool! Where are you getting the data to finetune the cv models for element extraction? I'm worried there isn't a robust enough dataset to be able to build a detection model that will generalize to all of the slightly different standards each discipline (and each firm for that matter) use.
- wcisco17 6mo agogood q — we don't train on customer drawings. Our detection models are trained on a curated dataset of architectural drawings we've sourced and labeled ourselves, focused on the most common fixture and element types across CSI divisions. The generalization problem you're pointing at is real and it's the hardest part of this. Our approach is to keep the detection scope tight — rather than trying to generalize across every firm's conventions, we train on a small but high-quality set of fixtures and optimize for precision within that scope. The result is high confidence outputs on the elements we support, rather than mediocre coverage across everything. We're expanding the detection surface incrementally as we validate accuracy division by division!
- dylan604 6mo agoHow in the world is an answer to a question from the account posting TFA replying directly to said question getting killed?
- sreekanth850 6mo agoWe’re taking a different path, building a parsing engine that converts CAD (DWG/DXF) into fully structured JSON with preserved semantics (no ML in the critical path).We also have a separate GIS parser that extracts vector data (features, layers, geometries) independently, Like to know how you handle consistency and reproducibility across runs using models and how you make it affordable, especially at scale. because as far as i know CAD and GIS need precision and accuracy.
- oneneptune 6mo agoIs this a service / product you plan to offer outwardly? I'd be interested in learning more. Use case: estimation.
- sreekanth850 6mo agoHappy to say that yes. We are in final round of polishing. mostly opening in couple of weeks. We are mainly targeting such uses cases where you can add CAD files into RAG or analytics or search pipeline without losing source of truth or geometry. I will definitely post here when we are ready, keep an eye and it will be free during beta, so you can play how much you want with it.
- oneneptune 6mo agoI think given the scale of projects worked on / being estimated (8 to 9 figure projects) -- it's unlikely we'd be willing to test on our real CAD files. Any chance for enterprise hosted solutions that aren't on the cloud?
- sreekanth850 6mo agoThat is the catch, yes on premise air gapped will be provided, this is purely inbuilt parsers no cloud dependency. We will also have a managed dedicated environment, if you don't want to manage the complex infra yourself. Even in Hosted model, we have provision to use your own s3 storage (only used for async parsing pipeline and file will be wiped after 3 hours)so file never touches our disc. We had considered this from a customer point of view and while designing the system. In my early career i had worked in GIS industry and know the privacy and the data security that is required for CAD and GIS files.
- i18nagentai 6mo ago[flagged]
- wcisco17 6mo agoYeah OCR for technical is largely solved we're targeting the construction documents space For construction specs we have a few endpoints: - https://www.getanchorgrid.com/developer/docs/endpoints/specs-parse https://www.getanchorgrid.com/developer/docs/endpoints/specs... - https://www.getanchorgrid.com/developer/docs/endpoints/specs-content-extract https://www.getanchorgrid.com/developer/docs/endpoints/specs... so you would want these documents translated lets say to German, mandarin, ect?
- petee 6mo agoI ran the example doors given and it missed 9 swinging doors, some that were in double swing pairs, and a few that were just out on their own not clustered. Not bad overall though
- wcisco17 6mo agoYep we're constantly improving we're currently above 0.87 for doors we're thinking of adding a params for the ROC curve so that you can decide your own optimal thresholds depend on when false positive true positive rate is acceptable
- petee 6mo agoOh nice! I spend a good amount of time eyeballing drawings for overlooked details, so even finding most is a handy tool to me as my brain can skip the marked areas
- wcisco17 6mo agoLovely. Are you in the construction space or are you a dev or both?
- petee 6mo agoConstruction, coding is a hobby from before I realized a desk wasn't for me. Sadily we are always under NDAs, so using a tool like this would require a lot of hoop jumping unless it definitely didn't cache or anything
- h317 6mo agoI cannot wait for the day when tech companies become players in the construction industry because it looks like it is the only way forward to make a change. To think that everything has been digitalized a long time ago, yet contract law cannot properly deal with delineating responsibilities between GC and Architects, who are still sending 2D drawings to each other. Imagine, all this information about quantities and door types (and everything else) is already available and produced by the architect's team, BUT they cannot share it! Because if they do, they are responsible for the numbers in case something is wrong. So now there is this circus of: Arch technologist making the base drawing with doors. GC receives documents, counts doors for verification, and sends them to the sub. Subcontractor looks at these drawings, counts them again, and sends data to the supplier. Guess what, the supplier also looks, counts, confirms, and back we go. Though I think robotics will change all of that. And when we have some sort of bot assistance, big tech players will have a bigger leverage in this, which will lead to the proper change management architecture. Anyway, cool product. Anything to help with estimation. Really hope it gets traction.
- punnerud 6mo agoI had a job as HVAC engineer for the upgraded Oslo Airport back in 2011; started doing HVAC work for 3 weeks the rest was programming trying to make the rest of people more efficient. Made an Excel sheet with a lot of macros to manage all the drawing of the airport. That’s why I switched to programming when I continued to study, and did not want to come back before I got more experience. They even gave me a big desk at Trondheim/Tyholt so I could help them with the software during my studies.
- deleted 6mo ago[deleted]
- punnerud 6mo ago«Why we did it»; would rather have a “How we did it”. The why gave me AI generated marketing material feelings. Tailscale’s article about NAT traversal is an example of how to write “how we did it”: https://tailscale.com/blog/how-nat-traversal-works https://tailscale.com/blog/how-nat-traversal-works
- wcisco17 6mo agoFair point and thanks for the tip. No AI here though.
- tomedwrds 6mo agoI have been working on an extension of this problem lately that involves extracting all doors + any details about those doors to produce quotes. I have found giving the pdf to codex pretty good at it as it can take subcrops of the plans to look at certain areas of high noise in more detail. Only downside is cost is quite high.
- nostrapollo 6mo agoFirst off, congrats on the launch! Construction is a tough market to build in. My personal view after being in it a for a few years is that there is no shortage of MVPs. In fact there is an MVP for every problem at every level (or at least it feels that way) but construction is /vast/ and the rough edges that seem juicy at first, in practice are optimizations rather than bottlenecks for constructors. I hope you succeed because it would be great to have a standard API for this data, but I would advise on one of two directions: become the standard by being close to 100% accurate at finding symbols (one symbol doesn't seem to cut it in our testing) or make a great, comprehensive workflow for a small subset of the market and become standard that way. In both cases, you cannot do a broad 'market test', you need to spend many hours with a specific sub-set of users in construction. Disclaimer: I'm a co-founder of Provision.
- mmethodz 6mo agoDo that for Finnish construction documents. My parser is 30000+ lines candidate based but the lack of standards and the Finnish language...
- wcisco17 6mo agoHave you tried using it with Finnish construction documents? It should work for the detections that cover drawings.
- copypaper 6mo agoVery interesting. Im on vacation but will check this out at work next week. What is the maximum resolution you support for PDFs? The max gemini will do is 3072x3072. We have plans that are 10x that size.
- alexeischiopu 6mo agoWhat divisions information do you need?
- copypaper 6mo agoMainly 09, but also 05 and 07.
- alexeischiopu 6mo agoWon’t get to that soon. Focusing on MEP with some architectural elements).
- ichamo 6mo agoReally interesting to see this space developing. I'm building a masonry-specific quantity takeoff tool (vision model extraction into a parametric domain model that spits out bid-ready quantities) and the "data prison" framing resonates hard. One thing I've learned going deep in a single trade: the distance between "structured JSON from a drawing" and "numbers an estimator will bid with" is enormous. I've been really impressed with Bobyard and SketchDeck especially. h317's point about the liability-driven re-counting circus is spot on. Each party in the chain needs to own their numbers. Revit could have solved this a long time ago had this not been the case. An API that makes each individual count faster is valuable but it doesn't collapse the chain. Would love to talk to anyone else building in this space.
- gsampsonva 6mo agoHow can this tool help easy my workload? I'm already pretty overwhelmed.
- testUser1228 6mo agoI know its been a few days, but have you looked into the new Bluebeam offerings and do you see that as competition for you guys? https://www.bluebeam.com/bluebeam-max/ https://www.bluebeam.com/bluebeam-max/ Their first example is counting fixtures
- wcisco17 6mo agoFair callout — Bluebeam Max does touch estimation. That said, we've talked with 20+ subs and almost none know them know exists. The reality is people that work in construction (Excluding field work), refers to AI as a scam and compares it to the crypto hype back in 18 .. compares it to crypto in 2018 — all hype, no landing.. seriously they do not like it. I built this selfishly. Eight months ago I wished I had a programmatic interface to interact with drawings. So I built one. last point: our customers aren't just doing takeoffs and they aren't just subs or gc's either — they're building tools in the construction tech space and estimation is one use case. The broader opportunity is making all that structured data accessible. great q!! Also I didn't see Claude there "ai" tool (a bit weird they are letting the model providers own the entire interface) count any fixtures, and if it did it was probably pulling it from the markup's table which is enabled via their api, which you can technically just slap an llm on top of it. But hey kudos to them - this space is not easy. (https://developers.bluebeam.com/s/studio?language=en_US https://developers.bluebeam.com/s/studio?language=en_US)