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OCR for construction documents does not work, we fixed it

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Re: OCR for construction documents does not work, we fixed it

#31

Post by fithisux »

kube-system wrote: post #10
pwagland wrote: post #9

Earlier quoted context omitted.

PDF files can be signed, that is tamper resistance. Tamper resistance doesn't have to make any difference to the readability of the document.

So 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.

True but you can make modified copies if you reverse engineer it with OCR.

Re: OCR for construction documents does not work, we fixed it

#32

Post by jsidney »

wang_li wrote: post #27
wcisco17 wrote: post #22

Earlier quoted context omitted.

Anyone 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…

Why 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.

Only 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.

Re: OCR for construction documents does not work, we fixed it

#34

Post by cyanydeez »

wang_li wrote: post #27
wcisco17 wrote: post #22

Earlier quoted context omitted.

Anyone 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…

Why 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.

Oh you sweet summer child. These draws are anywhere from 0 to 120 years old and might just be something pulled out of a floppy disk from 1970 to scanned in coffee ridden pieces of paper sitting in a desk folded a hundred times.

The world in which metadata is a common thing attached to any file doesn't exist, and probably never will, no matter how much you try to improve CAD work flow.

Re: OCR for construction documents does not work, we fixed it

#35

Post by frogguy »

Looks 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.

Re: OCR for construction documents does not work, we fixed it

#36

Post by wcisco17 »

frogguy wrote: post #35

Looks 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.

good 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!

Re: OCR for construction documents does not work, we fixed it

#37

Post by kube-system »

fithisux wrote: post #30
kube-system wrote: post #5

Earlier quoted context omitted.

Since when is tamper resistance a part of PDF or any common image format?

You can't change a PDF, it is by design to be not easy to OCRed

PDFs are merely an collection of objects, that can be plainly read by reading the file -- some of those are straight up plain text that doesn't even need to be OCR'd, it can be simply extracted. It is also possible to embed image objects in PDFs, (this is common for scanned files) which might be what you are thinking of. But this is not a design feature of PDF, but rather the output format of a scanner: an image. Editing PDFs is a simple matter of simply editing a file, which you can do plainly as you would any other.

Re: OCR for construction documents does not work, we fixed it

#39

Post by sreekanth850 »

We’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.

Re: OCR for construction documents does not work, we fixed it

#40

Post by testUser1228 »

alexeischiopu wrote: post #12
Iulioh wrote: post #6

When will this be available for 30000x8000px electrical diagrams? I have to make a BOM and oh boy I hate my job

I’m building a similar platform, with electrical being furthest ahead - SLD, panels, lights, power, comms. Also do doors, windows, and mechanical equipment. dm, and I can include you in the next preview.

I'm not sure how to dm on here, but I'm very interested
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