File talk:Qr-code-ver-40.png

Image doesn't appear to scan. Perhaps the PNG is suffering from compression artifacts? — Preceding unsigned comment added by 144.118.3.35 (talk)

PNGs don't have compression artifacts, because they aren't lossy like JPEGs and such. Unless you're saying it was passed through a lossy format before being converted to PNG? Even then, it being a QR code, there's so much error correction, it should be scannable anyway. In fact, I find it does scan if upscaled without interpolation (so the modules are squares of, say, 4×4 pixels), so probably scanning such large codes with single-pixel or blurry modules is difficult. Having the weird artifacts of a camera pointed at a video display (like Moiré patterns, for instance) doesn't help either. Moral of the story: avoid using huge QR codes unless really necessary, and if necessary, don't use single-pixel modules. ddawson (talk) 18:32, 2 January 2019 (UTC)