diff --git a/exp/kerokero/prepare_data.py b/exp/kerokero/prepare_data.py
--- a/exp/kerokero/prepare_data.py
+++ b/exp/kerokero/prepare_data.py
@@ -113,6 +113,11 @@ def show(img,filename="x"):
 
 
 if __name__=="__main__":
-	root=sys.argv[1]
-	for d in traverseDirs(root):
-		harvestDir(d)
+	((trainImages,trainLabels),(testImages,testLabels))=loadDataset(sys.argv[1])
+	np.savez_compressed(
+		sys.argv[2],
+		trainImages=trainImages,
+		trainLabels=trainLabels,
+		testImages=testImages,
+		testLabels=testLabels
+	)