diff --git a/README.md b/README.md
index 3afd87c8..5d01014a 100644
--- a/README.md
+++ b/README.md
@@ -178,4 +178,4 @@ Feel free to contact us in the following ways:
 * Dingtalk group: 34059705
 * slack channel: #xquic in quicdev group
 
-  <img src="docs/images/dingtalk_group.png" width=200 alt="dingtalk group"/>
+  <img src="docs/images/dingtalk_group.JPG" width=200 alt="dingtalk group"/>
diff --git a/docs/images/dingtalk_group.JPG b/docs/images/dingtalk_group.JPG
new file mode 100644
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diff --git a/docs/images/dingtalk_group.png b/docs/images/dingtalk_group.png
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