diff --git a/tests/files/zopfli_mode.png b/tests/files/zopfli_mode.png
index 3f9bdb1a..82ca1f07 100644
Binary files a/tests/files/zopfli_mode.png and b/tests/files/zopfli_mode.png differ
diff --git a/tests/flags.rs b/tests/flags.rs
index 53d84a22..baf0ea69 100644
--- a/tests/flags.rs
+++ b/tests/flags.rs
@@ -686,9 +686,9 @@ fn zopfli_mode() {
         input,
         &output,
         &opts,
-        RGB,
+        INDEXED,
         BitDepth::Eight,
-        RGB,
+        INDEXED,
         BitDepth::Eight,
     );
 }