These unused member functions use other members that don't exist.

Upstream equivalent: https://sourceforge.net/p/mjpeg/Code/3513/

--- mjpegtools-2.2.1/y4mdenoise/Region2D.hh	2021-09-05 07:14:13.037372932 +0100
+++ mjpegtools-2.2.1/y4mdenoise/Region2D.hh	2025-07-04 18:59:57.891570454 +0100
@@ -404,6 +404,7 @@
 
 
 
+#if 0
 // Add the given horizontal extent to the region.
 template <class INDEX, class SIZE>
 template <class REGION, class REGION_TEMP>
@@ -480,6 +481,7 @@
 	PrintRegion (a_rTemp);
 	assert (false);
 }
+#endif
 
 
 
@@ -513,6 +515,7 @@
 
 
 
+#if 0
 // Make the current region represent the union between itself
 // and the other given region.
 template <class INDEX, class SIZE>
@@ -686,6 +689,7 @@
 	PrintRegion (a_rTemp);
 	assert (false);
 }
+#endif