Post #2499417

this QR code is printed at 4x scale on a 300 dpi printer so it has an effective resolution of 75 pixels per inch. this particular code is 1.687 inches wide and encodes 1,262 ascii characters, suggesting a data density of 0.443 kBpsi. I've done some testing and if I use my phone's zoom feature I can reliably scan this same code at only .75 inches wide, suggesting a possible data density of 2.24 kBpsi. larger QR codes are more dense, and in the extreme case of a 2kB code measuring 177 pixels wide, we would expect to see 2.61 kBpsi. for context, a GBA e-reader card can store "5824 bytes on two strips" and still have plenty of space in the middle of the card for artwork. if we did that with high-density QR codes it would require... 2.23 square inches, about 25% of a playing card, and a whopping 32% of a business card. the GBA e-reader is stupidly effective, probably because it's designed for a camera with a fixed focal length and isn't worried about data redundancy like the QR encoding is. I wonder how much farther I could push this if I implemented my own dotcode. also, kBpsi is fun to say!! https://sethmlarson.dev/dumping-nintendo-ereader-card-roms