diff --git a/nebula_decoders/include/nebula_decoders/nebula_decoders_common/point_filters/downsample_mask.hpp b/nebula_decoders/include/nebula_decoders/nebula_decoders_common/point_filters/downsample_mask.hpp
index f14420af..bc6ed40a 100644
--- a/nebula_decoders/include/nebula_decoders/nebula_decoders_common/point_filters/downsample_mask.hpp
+++ b/nebula_decoders/include/nebula_decoders/nebula_decoders_common/point_filters/downsample_mask.hpp
@@ -109,7 +109,8 @@ class DownsampleMaskFilter
 
     if (export_dithered_mask) {
       std::filesystem::path out_path{filename};
-      out_path = out_path.replace_extension("_dithered.png");
+      out_path = out_path.replace_filename(
+        out_path.stem().string() + "_dithered" + out_path.extension().string());
 
       try {
         dithered.write(out_path);