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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"

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Your comment (zoomed in Chrome on Win 10): 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

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) 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"

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/

[1] https://twitter.com/jtaylor

Here's the repo of their build process for the core tesseract emscripten build

https://github.com/naptha/tesseract-emscripten/blob/master/j... specifically the line for lepton

Hey just a reminder that this is a ShowHN which has its own rules. Honesty is okay but aim to be respectful.

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.

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