7 ms·

Although Google's API is certainly better, Tesseract.js should work similarly if you increase the font size. Screenshots taken on 'retina' devices are around th

Although Google's API is certainly better, Tesseract.js should work similarly if you increase the font size. Screenshots taken on 'retina' devices are around the smallest text it can handle well. Edit: A screenshot of the same text at a higher resolution: https://imgur.com/a/W7IGu https://imgur.com/a/W7IGu Tesseract.js output: https://imgur.com/a/niIfM https://imgur.com/a/niIfM "I am also a top professional on thumbtack which is a site for people looking for professional services like on gig salad. Please see my reviews from my clients there as well"

jaytaylor 10y ago
Your comment (zoomed in Chrome on Win 10): http://i.imgur.com/uuFhw90.png http://i.imgur.com/uuFhw90.png Tesseract.js analysis: Although Googie's API is certaihiy better, Tesseract.js should work simiiarly if you increase the font size. Screenshots taken on 'retiha’ devices are around the smailest text it can handie well. Edit: A screenshot of the same text at a higher resolution: httgs:[[imgurxomZaN/UGu Tesseract.js output: httgs://imguricom[a[hiIfM This is a neat toy, but not impressive compared to the results from tesseract-ocr/tesseract [0]: $ curl -s http://i.imgur.com/uuFhw90.png \ | tesseract stdin stdout Although Google's API is certainly better, Tesseract.js should work similarly if you increase the font size. Screenshots taken on 'retina' devices are around the smallest text it can handle well. Edit: A screenshot of the same text at a higher resolution: https:[ZimguncomlalWHGu Tesseract.js output: https:[[imgur.com[a[nilfM Notice how Tesseract.js results suffer from being unable to differentiate between n's and h's, i's and l's. [0] https://github.com/tesseract-ocr/tesseract https://github.com/tesseract-ocr/tesseract
- bijection 10y ago
  That's interesting! Given that Tesseract.js wraps an Emscripten'd copy of Tesseract, I would have expected close to identical performance. This might have to do with the way we threshold images, with the age of the tesseract version we're using, or both. I'll look into it! Edit: In addition to those differences, I think your font size is still a bit too small. On an unedited screenshot from a macbook (https://i.imgur.com/iv4ZdSt.png https://i.imgur.com/iv4ZdSt.png) I get Although Google's API is certainly better, Tesseract.js should work similarly if you increase the font size. Screenshots taken on 'retina' devices are around the smallest text it can handle well. Edit: A screenshot of the same text at a higher resolution: https:[[imgur.com[a[W7IGu Tesseract.js output: https:[[imgur.com[a[niIfM “I am also a top professional on thumbtack which is a site for people looking for professional services like on gig salad. Please see my reviews from my clients there as well"
  - jaytaylor 10y ago
    What do you mean by "emscripten'd"? Is Tesseract.js using emscripten to effectively bundle the 150KLOC of C/C++ from tesseract-ocr and the upstream dependency on leptonica [0]? If so, that's amazing! > This might have to do with the way we threshold images, > with the age of the tesseract version we're using, or > both. I'll look into it! I'd be very interested to hear about what is required to make it "match" native functionality. Please do drop me a line if/when you get it figured out! (I'm @jtaylor on twitter [1]) [0] http://www.leptonica.org/ http://www.leptonica.org/ [1] https://twitter.com/jtaylor https://twitter.com/jtaylor
    - mumphster 10y ago
      Here's the repo of their build process for the core tesseract emscripten build https://github.com/naptha/tesseract-emscripten/blob/master/javascript/Makefile#L4 https://github.com/naptha/tesseract-emscripten/blob/master/j... specifically the line for lepton
- brazzledazzle 10y ago
  Hey just a reminder that this is a ShowHN which has its own rules. Honesty is okay but aim to be respectful.
oriolid 10y ago
I've used Tesseract for a production OCR project some years ago, and can confirm too that it just doesn't work at screen resolution. On the other hand, performance on high DPI photos was quite OK. Google Vision API wasn't around at that time so I can't compare.

jaytaylor 10y ago

Your comment (zoomed in Chrome on Win 10): http://i.imgur.com/uuFhw90.png http://i.imgur.com/uuFhw90.png Tesseract.js analysis: Although Googie's API is certaihiy better, Tesseract.js should work simiiarly if you increase the font size. Screenshots taken on 'retiha’ devices are around the smailest text it can handie well. Edit: A screenshot of the same text at a higher resolution: httgs:[[imgurxomZaN/UGu Tesseract.js output: httgs://imguricom[a[hiIfM This is a neat toy, but not impressive compared to the results from tesseract-ocr/tesseract [0]: $ curl -s http://i.imgur.com/uuFhw90.png \ | tesseract stdin stdout Although Google's API is certainly better, Tesseract.js should work similarly if you increase the font size. Screenshots taken on 'retina' devices are around the smallest text it can handle well. Edit: A screenshot of the same text at a higher resolution: https:[ZimguncomlalWHGu Tesseract.js output: https:[[imgur.com[a[nilfM Notice how Tesseract.js results suffer from being unable to differentiate between n's and h's, i's and l's. [0] https://github.com/tesseract-ocr/tesseract https://github.com/tesseract-ocr/tesseract

bijection 10y ago
That's interesting! Given that Tesseract.js wraps an Emscripten'd copy of Tesseract, I would have expected close to identical performance. This might have to do with the way we threshold images, with the age of the tesseract version we're using, or both. I'll look into it! Edit: In addition to those differences, I think your font size is still a bit too small. On an unedited screenshot from a macbook (https://i.imgur.com/iv4ZdSt.png https://i.imgur.com/iv4ZdSt.png) I get Although Google's API is certainly better, Tesseract.js should work similarly if you increase the font size. Screenshots taken on 'retina' devices are around the smallest text it can handle well. Edit: A screenshot of the same text at a higher resolution: https:[[imgur.com[a[W7IGu Tesseract.js output: https:[[imgur.com[a[niIfM “I am also a top professional on thumbtack which is a site for people looking for professional services like on gig salad. Please see my reviews from my clients there as well"
- jaytaylor 10y ago
  What do you mean by "emscripten'd"? Is Tesseract.js using emscripten to effectively bundle the 150KLOC of C/C++ from tesseract-ocr and the upstream dependency on leptonica [0]? If so, that's amazing! > This might have to do with the way we threshold images, > with the age of the tesseract version we're using, or > both. I'll look into it! I'd be very interested to hear about what is required to make it "match" native functionality. Please do drop me a line if/when you get it figured out! (I'm @jtaylor on twitter [1]) [0] http://www.leptonica.org/ http://www.leptonica.org/ [1] https://twitter.com/jtaylor https://twitter.com/jtaylor
  - mumphster 10y ago
    Here's the repo of their build process for the core tesseract emscripten build https://github.com/naptha/tesseract-emscripten/blob/master/javascript/Makefile#L4 https://github.com/naptha/tesseract-emscripten/blob/master/j... specifically the line for lepton
brazzledazzle 10y ago
Hey just a reminder that this is a ShowHN which has its own rules. Honesty is okay but aim to be respectful.

oriolid 10y ago

I've used Tesseract for a production OCR project some years ago, and can confirm too that it just doesn't work at screen resolution. On the other hand, performance on high DPI photos was quite OK. Google Vision API wasn't around at that time so I can't compare.