Here's a half-baked idea I had while working on a couple of projects using NFC tags. It's a detour from a detour ...
Anyway, something appeals to me about the idea of exchanging images via NFC tags. I don't quite know where to go with this, but here's a start for when inspiration strikes and I get back to it.
The tags I have are NTAG215 which, according to NFC Tools can only hold 540 bytes (everything I've seen online says 504 🤷), so it presents a little bit of a challenge: I created a 16x16 PNG file and it was 1.3K. I used ImageMagick to convert to several other formats with the following results:
| Format | Size |
|---|---|
| BMP | 3.1k |
| Farbfeld | 2k |
| GIF | 2k |
| JPG | 2.5k |
Perhaps if I played around with various options I could do better.
For now, I've opted for a fixed pallette and am just storing the color index of each pixel as a UInt8. Since my pallette has only 16 entries, I could pack the info into a nybble. Maybe later. As it is, this allows me to store a 16x16 image in 257 bytes (one byte for image size, in case I don't want to stick with just 16x16)—which easily fits on the tag.
Originally I intended to implement simple paint functionality, but decided I'd rather get back to my actual project. Let me know if you have interesting ideas on where to go with this; just create an issue.