I have a very slight problem in that I went to grad school when professionals still used calculators, and real professionals used HP calculators. And so I still own, and use, a variety of HP scientific calculators. I can quit any time I want, I swear.
The HP-48 line (for instance) transferred files via an LED/photodiode pair. You'd point the calculators at each other and let them flash away until they were done. This seems to be that, but much better. Or at least much faster.
They were quite popular before Bluetooth (Bluetooth file transfers are actually a different physical layer for the same protocol called OBEX) and quite ironically interoperable across phone and PDA manufacturers, as far as I remember.
It’s extremely sad that we’ve gone from being able to send a photo or business card across manufacturers to needing (incredibly clever!) contortions like this, on vastly more powerful hardware that can literally talk to satellites and run local LLMs.
What I wouldn't give for a mobile>mobile or desktop/laptop>mobile cross platform file transfer that only required camera permissions at 2mbit/sec or similar speeds.
All of the non-internet ios > android file transfer options I've seen are very clunky.
I thought about this technology for bitcoin offline wallet. So like you'll get any mobile phone, install some bitcoin app, put it to aircraft mode (or even destroy all wireless chips if you can do that). Or just laptop. Then you'd use it to generate wallet, sign transaction and then QR this transaction and receive it via another phone which is connected to the internet. So private key is never leaving offline device and all communication with the outside world is through human-eye controllable channel. Should be impossible to compromise using digital methods (assuming that wallet application is trustworthy).
Coldcard does this with a microSD card which seems more secure than broadcasting light. Using open source wallet like Sparrow and running own Bitcoin node with Electrum server further improves security and privacy.
Wait why do the QR codes actually look like the video frames? I interpreted this as "convert the binary of an arbitrary file into a series of QR codes". Is that just a coincidence?
They overlayed the edges of the video frames on the QR codes, and then the built in error correction compensates for the missing data. It's explained in the paper.
And thus does the wheel of technology spin.
I have a very slight problem in that I went to grad school when professionals still used calculators, and real professionals used HP calculators. And so I still own, and use, a variety of HP scientific calculators. I can quit any time I want, I swear.
The HP-48 line (for instance) transferred files via an LED/photodiode pair. You'd point the calculators at each other and let them flash away until they were done. This seems to be that, but much better. Or at least much faster.
Infrared ports are basically that!
They were quite popular before Bluetooth (Bluetooth file transfers are actually a different physical layer for the same protocol called OBEX) and quite ironically interoperable across phone and PDA manufacturers, as far as I remember.
It’s extremely sad that we’ve gone from being able to send a photo or business card across manufacturers to needing (incredibly clever!) contortions like this, on vastly more powerful hardware that can literally talk to satellites and run local LLMs.
IrDA. I remember having it on laptops, palmtops, printers and such but I don’t think I ever actually used it.
https://en.wikipedia.org/wiki/Infrared_Data_Association
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TIL OBEX is older than Bluetooth.
"when professionals still used calculators"
Silly me and my slide rule. When your cells run out, I'll still be calculating logs like there is no tomorrow.
I also own a quite early Texas Instruments calculator (it was my Dad's and so are the slide rules) but I only keep that to spell out BOOBIES.
I am too young to have ever used a slide rule in anger, but that doesn't mean I don't have one. My mother's, when she went to grad school.
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An LED and a photodiode are basically a single pixel screen and camera, so this is basically that but in parallel.
Same as a Bluetooth or Wi-Fi antenna, if you squint hard enough :)
What I wouldn't give for a mobile>mobile or desktop/laptop>mobile cross platform file transfer that only required camera permissions at 2mbit/sec or similar speeds.
All of the non-internet ios > android file transfer options I've seen are very clunky.
This is really neat.
I stumbled across this recently: https://github.com/sz3/libcimbar
If you haven't already, try compressing the video using Handbrake to cut down on its size. 1 GB for 5 minutes is quite a lot.
I thought about this technology for bitcoin offline wallet. So like you'll get any mobile phone, install some bitcoin app, put it to aircraft mode (or even destroy all wireless chips if you can do that). Or just laptop. Then you'd use it to generate wallet, sign transaction and then QR this transaction and receive it via another phone which is connected to the internet. So private key is never leaving offline device and all communication with the outside world is through human-eye controllable channel. Should be impossible to compromise using digital methods (assuming that wallet application is trustworthy).
SeedSigner does this, using an RPi with screen/camera.
https://seedsigner.com
Coldcard does this with a microSD card which seems more secure than broadcasting light. Using open source wallet like Sparrow and running own Bitcoin node with Electrum server further improves security and privacy.
That’s what we did when we built air-gapped Bitcoin cold storage: https://github.com/square/subzero
Wait why do the QR codes actually look like the video frames? I interpreted this as "convert the binary of an arbitrary file into a series of QR codes". Is that just a coincidence?
They overlayed the edges of the video frames on the QR codes, and then the built in error correction compensates for the missing data. It's explained in the paper.
It’s like how QRs can be abused to appear like certain images, just a little stunt on top of the implementation
Please make a live demo version of this using only JavaScript and HTML :D
Seems like the site is down :(