correct for both 4 bytes per pixel and 2 bytes

examples/live.rs

@@ -126,7 +126,7 @@ fn main() -> anyhow::Result<()> {
                         };
                         let g = frame[i * 2];
                         let b = frame[i * 2 + 1];
-                        let out_i = (y + x * HEIGHT) * 2;
+                        let out_i = ((HEIGHT - 1 - y) + (WIDTH - 1 - x) * HEIGHT) * 4;
                         swapped[out_i..out_i + 4].copy_from_slice(&[0, r, g, b]);
                     }
                 }