diff --git a/src/gui/render_templates_hq.h b/src/gui/render_templates_hq.h
index 002f1fff..3bfd65e3 100644
--- a/src/gui/render_templates_hq.h
+++ b/src/gui/render_templates_hq.h
@@ -41,17 +41,17 @@ static inline bool diffYUV(Bit32u yuv1, Bit32u yuv2)
 	Bit32u mask;
 
 	diff = ((yuv1 & Ymask) - (yuv2 & Ymask));
-	mask = diff >> 31; // -1 if value < 0, 0 otherwise
+	mask = ((Bit32s)diff) >> 31; // ~1/-1 if value < 0, 0 otherwise
 	diff = (diff ^ mask) - mask; //-1: ~value + 1; 0: value
 	if (diff > trY) return true;
 
 	diff = ((yuv1 & Umask) - (yuv2 & Umask));
-	mask = diff >> 31; // -1 if value < 0, 0 otherwise
+	mask = ((Bit32s)diff)>> 31; // ~1/-1 if value < 0, 0 otherwise
 	diff = (diff ^ mask) - mask; //-1: ~value + 1; 0: value
 	if (diff > trU) return true;
 
 	diff = ((yuv1 & Vmask) - (yuv2 & Vmask));
-	mask = diff >> 31; // -1 if value < 0, 0 otherwise
+	mask = ((Bit32s)diff) >> 31; // ~1/-1 if value < 0, 0 otherwise
 	diff = (diff ^ mask) - mask; //-1: ~value + 1; 0: value
 	if (diff > trV) return true;