https://codeberg.org/blast/blastqr
Hello! I’ve been working on blastQR for a couple of years now and I thought this community might find it useful. Feel free to try it and ask me anything!
blastQR is a fully open-source file transfer app and protocol that works completely offline. You can even use it in airplane mode. Data is transferred through sequences of QR codes displayed on a sender device and scanned by a receiver device’s camera. It uses RaptorQ codes so the receiver can recover the file from any sufficiently large subset of frames.
Note that although I have made use of AI as a coding assistant I do not consider this to be a vibe-coded app and I do plan to continue improving it and supporting it in the future.
See video of blastQR in action: https://github.com/user-attachments/assets/038a2567-70c8-47c8-b165-dea858d1aef3
Here are some of the key features:
- Works fully offline: No internet, Wi-Fi, Bluetooth or servers. Your data stays offline.
- One-to-many distribution: Share the same file with multiple devices simultaneously using a single blastQR broadcast.
- Cross-platform: Android, iOS, macOS, Linux and Windows, plus a command-line tool that can send from a terminal, even over SSH.
- Password encryption: You can optionally encrypt files with an auto-generated password or a custom one.
- Media compression: The app supports lossy image compression and video transcoding for quicker transfers.
- Multiple codes on screen: Shows multiple QR codes at once for higher speed. With 8 codes at 60 fps, transfers peak at around 1.4 MB/s.
- Send multiple files in one go: They’re zipped into one transfer and unpacked into separate files on the receiver.
- Sound feedback: The receiver plays a short tone when it has the whole file, and the sender stops automatically when it hears it.
- Start scanning at any point: No need to catch every code, just keep the camera on the screen until it’s done. Blurry or missed codes don’t matter.
- Regular QR scanner: You can also scan normal QR codes and save them.
- Open protocol that other apps can implement
- Built-in file manager
I’m trying to build a small community around the project so it can be improved and maintained and so it can reach more people in the future.
Downloads for all platforms can be found here: https://codeberg.org/blast/blastqr/releases/latest
Thank you for the suggestion!
dev.blastapps.blastqr 60:E3:A6:C0:63:1D:C3:A0:0C:78:E4:C9:E4:89:B3:03:4F:A9:7D:49:D0:B9:3E:CF:56:B2:33:A8:C3:DD:F6:83it’s been added to the readme as well.
Dope, thank you very much!
Two more questions: Is there a way to set 8 codes for sending in the flatpak version, or is that limited to 6? Any idea why a pixel 8 pro on graphene wouldn’t allow 120/240 fps receiving? Highest I’ve been able to choose and test is 60fps. was thinking that it may be the resolution cap, but an iPhone comparison ran at 240fps with the same res (I think).
The app is limited to 6 right now but I’ll work on increasing it! The CLI tool does allows up to 12. Make sure you use Ghostty or Kitty for high frame rates if you do decide to try it.
A lot of phones cap the camera preview at 30fps actually so 60fps is quite good already. From the devices I tested only the iPhone let me select 60,120,240. You can see some benchmarks here: https://codeberg.org/blast/blastqr#real-world-benchmarks I don’t think you are missing out on performance if you can scan at 60fps. I recall at 120 the cpu was starting to be the bottleneck but I’ll have to do some more testing to confirm.
Yeah, thanks for the input. i did realise that the iPhone too performs best at 60FPS actually(anecdotally).
This is truly a cool project. thanks for your work!