Hacker News new | past | comments | ask | show | jobs | submit login

Here is a good demo of a streaming qr solution. Not ours but a good demo of the concept.


We use a similar method for offline wallet transfers of private crypto keys. I’ll note a couple things. Keep the frame simple and not too dense. Be careful on ecc settings. Higher res camera androids to be slower in our testing. Be ready to loop the series to catch missed frames. Gives your frames and order context. If it’s really sensitive dat, encrypt it before encoding you QR. assume the video can be stolen from a camera. Inject noisy frames To help obfuscate.

Another animated QR data transfer that uses fountain codes: https://github.com/divan/txqr

Hey, I wanted to use your library to send data from computer A to computer B, but I don't speak Go yet.

How easy would it be to implement a txqr reader for desktop? Piping zbarcam's output could be the easiest way.

Have you got any directions for me to do it? It would be a great addition to txqr!


I'm actually planning to make Go+Flutter application, which will work on iOS/Android, Desktop and Web. Out of curiosity, what's your use case?

I would use this in a security context.

I want to use a one-time pad with a friend. That requires generating a fully random file that I then need to send to my friend (physically). I don't have an Ethernet port on my machine to send the file on the wire, and I don't want to rely on weaker cryptography (WiFI, aes) to send this file (basically, everything is weaker than a one-time pad). I also don't want to leave undeletable traces of my one-time pad on a flash drive.

So what's left is the actual screen of the device, provided I don't have any hidden cameras where I live.

I could use a hard drive and then shred the secrets, but nothing is proven regarding the actual deletion of the files, and QR codes are much cooler!

Did you consider using the front camera for bidirectional phone-to-phone communication? That could allow frame re-transmits which would increase the data rate a lot.

That'd be definitely a whole new level, yes, but I think the simplicity of one-way diode communication has its own benefits.

I've been wondering how one could efficiently and reliably pack arbitrary data into YouTube videos, a hacky way to get free and obfuscated data storage. Streaming QR codes has been the most promising way I can think of, particularly since they offer resilience against YouTube's video re-encoding process and are standardized for far larger codes, which could be easily fit in a video for later parsing out by a tool. You could probably embed even greater data densities with a color QR solution too.

Put your data into description and comments.

Applications are open for YC Winter 2021

Guidelines | FAQ | Support | API | Security | Lists | Bookmarklet | Legal | Apply to YC | Contact