diff --git a/assets/images/sharp-brain-overlay.jpg b/assets/images/sharp-brain-overlay.jpg
new file mode 100644
index 0000000..33c4407
Binary files /dev/null and b/assets/images/sharp-brain-overlay.jpg differ
diff --git a/assets/images/sharp-brain-overlay.png b/assets/images/sharp-brain-overlay.png
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diff --git a/collections/_beginners/get-started.md b/collections/_beginners/get-started.md
index 1b648cf..0d6a586 100644
--- a/collections/_beginners/get-started.md
+++ b/collections/_beginners/get-started.md
@@ -227,7 +227,7 @@ Shift キー・Ctrl キー・Alt キーは現実のキーボードに近い配
 
 [SHARP Brain](https://github.com/tslmy/sharp-brain-keyboard-overlay) は Buildroot 版に標準で含まれています。Debian/Brainux 版では Packagecloud からインストールできます。以下に SHARP Brain の表示例を示します。
 
-<img src="/assets/images/sharp-brain-overlay.png" width=640px>
+<img src="/assets/images/sharp-brain-overlay.jpg" width=640px>
 
 
 ## 電源を切る