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 > generate a marble-like pattern bitmap image, blazing fast.
 
-![](./images/sample1.bmp)
+![](./images/sample.gif)
 
 Written in pure C without librairies.
 
diff --git a/images/sample.gif b/images/sample.gif
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diff --git a/images/sample1.bmp b/images/sample1.bmp
deleted file mode 100644
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