diff --git a/main.py b/main.py
index 5d562a2..11c0793 100644
--- a/main.py
+++ b/main.py
@@ -1,4 +1,5 @@
 import argparse
+import os
 
 from schema import InstructionSetSchema
 
@@ -19,11 +20,15 @@ description = """Examples:
 if __name__ == "__main__":
     parser = argparse.ArgumentParser(description=description, formatter_class=argparse.RawTextHelpFormatter)
     parser.add_argument("schema", help="Path to the schema description. Accepted formats are: YAML, JSON and XML")
-    parser.add_argument("-o", "--output", help="Output path", default="out.jpg")
+    parser.add_argument("-o", "--output", help="Output path. By default, the output file will have the same name as the schema description with the extension .png")
     parser.add_argument("-c", "--config", help="Path to the config file", default="config.json")
     parser.add_argument("-D", "--display", help="Enable pygame display of the result", action="store_true")
     
     args = parser.parse_args()
     
+    output = args.output
+    if output is None:
+        output = os.path.splitext(args.schema)[0] + ".png"
+    
     schema = InstructionSetSchema(args.schema, args.config, args.display)
-    schema.save(args.output)
\ No newline at end of file
+    schema.save(output)
\ No newline at end of file