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This is pretty awesome. I would like to see the same thing for the decoder.
by bb88 2y ago
This is pretty awesome. I would like to see the same thing for the decoder.
- smitelli 2y agoSame. I always marvel at how my phone can decode a badly lit, blurry, 1/4 out of frame QR code as quickly as it does.
- bb88 2y agoMy first instinct would be to go look at the discrete cosine transform that JPEG uses. But I don't know how to do the other parts like aligning and using the timing patterns.
- kfl 2y agoMaybe you'll enjoy Piko and blinry's guide on reading QR codes without a computer: https://qr.blinry.org/ https://qr.blinry.org/
- bb88 2y agoYeah interesting, but not really any different than the original content. Maybe a little easier to grok. I was looking for algorithms to extract out a QR code from an image.
- phoronixrly 2y agoYeah, I've been looking for a guide to implementing qr readers from 0. Explicitly not 'oh just plug in this CV library in, feed it the image and it spits out the result' like all the stuff I find in Google on the topic. I am looking for a guide that walks you through implementing all the algorithms necessary after you have the decoded raw image data.
- vrighter 2y agofind a copy of the standard. A version of it is floating online. The latest version just added some clarifications, but is not needed. I built an implementation out of that, though the error correction part, of course, I had to learn somewhere else. But the spec is very readable