Warum viele QR-Codes nicht scannen: die vergessene weiße Ruhezone

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Ein QR-Code lässt sich oft nicht scannen, obwohl er korrekt aussieht, weil der leere Rand um das Muster fehlt. Diese sogenannte Ruhezone hilft der Kamera, den Code vom Text oder Bildern in der Umgebung zu unterscheiden. Der Standard empfiehlt mindestens vier Module Abstand auf allen Seiten. Typische Fehler sind zu enge Platzierung an Rahmen, unruhige Hintergründe oder zu starkes Verkleinern des Codes. Der Autor rät zu einem freien Rand in Hintergrundfarbe und einem Test auf einem echten Smartphone in Druckgröße; er bietet außerdem einen kostenpflichtigen Generator an, der die Ruhezone automatisch einhält.

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