matrix-sdk-qrcode-0.15.0 has been yanked.
matrix-sdk-qrcode is a crate to easily generate and parse QR codes for interactive verification using QR codes in Matrix.
Usage
This is probably not the crate you are looking for, it's used internally in the matrix-sdk.
If you still want to play with QR codes, here is a helpful example.
Encode into a QR code
use ;
use Luma;