diff --git a/src/debug.h b/src/debug.h
index 52b5918d..d8035449 100644
--- a/src/debug.h
+++ b/src/debug.h
@@ -16,6 +16,6 @@
 
 FILE * open_cu_file(char *filename);
 void close_cu_file(FILE *fp);
-unsigned render_cu_file(encoder_control *encoder, unsigned depth, uint16_t xCtb, uint16_t yCtb, FILE *fp);
+unsigned render_cu_file(encoder_control *encoder, unsigned depth, uint16_t x_cu, uint16_t y_cu, FILE *fp);
 
 #endif