diff --git a/opengl/include/EGL/eglext.h b/opengl/include/EGL/eglext.h
index 4569b87..4c4cd4e 100644
--- a/opengl/include/EGL/eglext.h
+++ b/opengl/include/EGL/eglext.h
@@ -704,6 +704,7 @@
 #define EGL_SMPTE2086_WHITE_POINT_Y_EXT   0x3348
 #define EGL_SMPTE2086_MAX_LUMINANCE_EXT   0x3349
 #define EGL_SMPTE2086_MIN_LUMINANCE_EXT   0x334A
+#define EGL_METADATA_SCALING_EXT          50000
 #endif /* EGL_EXT_surface_SMPTE2086_metadata */
 
 #ifdef __cplusplus