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Show HN: QuaggaJS, a barcode scanner written in JavaScript

serratus.github.io

21–28 of 28 posts

Re: Show HN: QuaggaJS, a barcode scanner written in JavaScript

#21
post #9

This is great, but using the example with the webcam stream I could not get one correct reading of a barcode.

Have you really tried with Code128 or EAN13 encoded barcodes? In the demo, you can switch between those two modes. Make sure your camera has an auto-focus built in, because blurry images are not recognized robustly enough.

Re: Show HN: QuaggaJS, a barcode scanner written in JavaScript

#22

At present there is only one bar code scanner on firefoxos marketplace, with this library it looks like where will be better ones. Maybe consider making a quick FFOS App?

Yeah, I already tried the webpage on my Flame and it worked out of the box. This might be a great app for the FF-OS store indeed.

Re: Show HN: QuaggaJS, a barcode scanner written in JavaScript

#23
post #5
post #2

Invariant to scale and rotation in JS on mobile? That's fantastic! I just tested the Red Laser native app on my phone and it can handle scale/rotation too. But I never thought about rotation for the Red Laser app and always tried to align it properly between the [ ] brackets. I think apps that support scale/rotation should not show [ ] brackets but instead a central red +. Haven't dug deeply into how barcode_locator.…

There are a range of different methods that can be used, but your guess is probably correct regardless of which method you use: "breaking the image into smaller 'patches' and looping through those to look for chunks of a barcode". I would probably train a classifier (SVM or similar) using some rotation invariant feature, such as DAISY or ORB (BRIEF). I tried something similar for CRF image segmentation. This is might…

Thanks for this interesting input. I don't have much experience with classifiers, nor if they work well in JavaScript. I already implemented FAST and BRIEF in another project, but this solution was neither scale, nor rotation invariant. ORB seems to be a better fit for that. How would you implement your idea in JS?

Re: Show HN: QuaggaJS, a barcode scanner written in JavaScript

#24
Being able to scan barcodes using a web app is pretty cool. I used something similar when I was tinkering with transmitting data visually for the handshake step of webrtc: http://franklinta.com/2014/10/19/serverless-webrtc-using-qr-....

I used Lazarsoft's javascript QR code scanner which worked, but it wasn't very robust since it was a manual port of an early version of zxing. It is pretty easy to compile the c++ branch of zxing v2.3 using emscripten but it is a pain to optimize: https://github.com/fta2012/zxing-emscripten (or demo link: http://fta2012.github.io/zxing-emscripten/).

Re: Show HN: QuaggaJS, a barcode scanner written in JavaScript

#25

At present there is only one bar code scanner on firefoxos marketplace, with this library it looks like where will be better ones. Maybe consider making a quick FFOS App?

The problem of Firefox OS is the fix focus camera of over 1 meter and the max 5 mega pixel resolution. You can't get sharp barcode images. They are either blurry while to near, or too small while in focus.

I've build a Firefox OS app [1] that is theoretically enabled to scan barcodes, but it won't work with most devices out there.

[1] https://marketplace.firefox.com/app/qr-reader

Re: Show HN: QuaggaJS, a barcode scanner written in JavaScript

#27
post #25

At present there is only one bar code scanner on firefoxos marketplace, with this library it looks like where will be better ones. Maybe consider making a quick FFOS App?

The problem of Firefox OS is the fix focus camera of over 1 meter and the max 5 mega pixel resolution. You can't get sharp barcode images. They are either blurry while to near, or too small while in focus. I've build a Firefox OS app [1] that is theoretically enabled to scan barcodes, but it won't work with most devices out there. [1] https://marketplace.firefox.com/app/qr-reader

It's too bad that most of the problems when scanning barcodes are related to the missing auto-focus in browsers. I really hope this gets sorted out in the near feature.

I just tried your app and reading QR codes works really well. You are using an emscripten version of ZBar, right?

Re: Show HN: QuaggaJS, a barcode scanner written in JavaScript

#28

At present there is only one bar code scanner on firefoxos marketplace, with this library it looks like where will be better ones. Maybe consider making a quick FFOS App?

Yeah, I already tried the webpage on my Flame and it worked out of the box. This might be a great app for the FF-OS store indeed.

Hey there fellow flame user! I also have one, and yeah, it would make a great addition!

at the very least, it can be a web-webapp (firefoxOS let's you declare app manifests for online sites)

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