diff --git a/tools/cg2glsl.py b/tools/cg2glsl.py
index 30cc2abdef..bb3535f528 100755
--- a/tools/cg2glsl.py
+++ b/tools/cg2glsl.py
@@ -97,6 +97,7 @@ def no_uniform(elem):
          '_video_size',
          '_texture_size',
          '_output_size',
+         '_output_dummy_size',
          '_frame_count',
          '_frame_direction',
          'sampler2D'