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Office-open-xml-viewer: Office XML document viewer that renders to HTML Canvas

147 points · 54 comments · 3 days ago · maxloh

github.com

dmd3 days ago
So I just tried this with a bunch of medium-complex documents and it's wildly wrong. I suspect the authors have never seen an actually complicated Word document?
bobajeff3 days ago
For those interested here * is a similar project that I believe is *not* vibe coded posted a few weeks ago **.
* https://github.com/eigenpal/docx-editor
** https://smackernews.com/item/48228411 HN
gigel823 days ago
If someone actually got "pixel-faithful" Office documents rendering correctly, MS would be screwed. That's actually really important for a lot of companies that carry around decades-old templates that never look exactly right in LibreOffice or any other software that attempted to replicate it.
The slightest misalignment of a paragraph means a line on page 27 of 120 now moved down by 2 pixels, screwing everything else out of alignment. Yes, plenty of companies pay Microsoft 365 subscriptions because of exactly this reason; it sounds ludicrous when you think they could just pay someone to replicate the formatting in a different suite a lot less than the subscription costs, but that's not how it works...
jbgt3 days ago
Interesting because I'm building ooxml-cli right now, for editing pptx, docx, xlsx. At work I had to adapt a pptx to a corporate template and tried via agent. It kept failing so I started building and then it was able to relatively quick and accurate do what I needed. Then I needed it to make tables, add pictures. Recently wanted to get data from an xslx and replace text in a presentation etc.
So the tool is growing and maybe this would be interesting to have as the non LibreOffice dependent viewer...
jsmilker3 days ago
I ran it against some of our internal test files, and it failed on all of them how was this project even tested for proper compliance
int0x293 days ago
Misread that as open office xml not office open xml. I wish the standards were named more differently. They are too easy to confuse
wis3 days ago
Very nice, the rendered demo for all the file types appear to render flawlessly and load instantly on page load, and looking in the DevTools the parsers are split into different Wasm bundles for each file type xslx, docx and pptx:
```
  docx 458kb raw 217kb gzipped
  pptx 574kb raw 253kb gzipped
  xslx 601kb raw 269kb gzipped
```
I expected the Wasm bundles to be large and a lot more bigger than that for some reason.
ChatGPT.com can benefit from using this library (or such a library) for rendering a preview of the file in a side panel on the right, instead of just giving me a download link to the outputted/transformed docx/pptx/xslx file.
lovasoa3 days ago
I tried a few PPTX files from consulting firms that are available online. The rendering does not seem to be truly pixel-perfect, but all of them were quite readable and had a good layout, which is already an impressive feat.
phplovesong3 days ago
Its kind of sad that the first thing in the repo is a mention that no human was involved in the programming.
vlmutolo3 days ago
Pretty cool, rendering PowerPoint files to an image is probably the only way for LLMs to make sense of them.
Does this work in Cloudflare’s workerd environment? Would be nice to have a cheap serverless render -> LLM (GLM-OCR / PaddleOCR) -> Markdown pipeline for the various MS Office formats.
Jaxkr3 days ago
I literally had to solve the "preview Office files in the browser" problem last week. I couldn't find a decent solution, so I ended up making a endpoint that ran the files through headless libreoffice on the server to convert them to PDF.
For PPTX and DOCX, this solution is slightly worse than libreoffice conversion (this does not appear to output highlightable text, while PDF conversion does).
However, the XLSX preview BLEW my mind considering this was AI coded. Really good, even interactive!
virajk_313 days ago
I have been working on a similar implementation. However, wanted to understand whether you were able to make changes to the rendered content and then download the updated file again. will go through your code in detail.. Thanks.
kevlened3 days ago
From my experience, the team that's the closest to open-source pixel-perfect Word support is https://github.com/superdoc-dev/superdoc (unaffiliated)
xuanlin3143 days ago
Rendering Office XML directly to Canvas is clever — avoids the heavy DOM tree for large documents. Does it handle embedded media (images/charts) or just text + formatting for now?
sublinear3 days ago
office-open-xml-viewer
bulder3 days ago
The post title about it being "pixel-faithful" is a bit strange. I don't see that claim in the repo, and they don't seem to even claim full feature support at the moment. And for the features marked as supported in .pptx's, it does seem that at least slide image backgrounds and bullet point images aren't actually working, and some text objects have inverted text colors. Seems quite far away from being pixel-faithful in fact.
freakynit3 days ago
"Built entirely by Claude through iterative prompting."
Holy cow!!

news.ycombinator.com/item?id=48436863