Commit c8010dcb3 for imagemagick.org

commit c8010dcb3a00a1df718a6c4ad9162957c10f2ef9
Author: Cristy <urban-warrior@imagemagick.org>
Date:   Sat Nov 7 10:37:26 2026 -0500

    add a threshold guard for HDRI mode

diff --git a/MagickCore/quantum-private.h b/MagickCore/quantum-private.h
index c4ea9fc5e..54ba17763 100644
--- a/MagickCore/quantum-private.h
+++ b/MagickCore/quantum-private.h
@@ -352,13 +352,18 @@ static inline QuantumAny ScaleQuantumToAny(const Quantum quantum,
 #if defined(MAGICKCORE_HDRI_SUPPORT)
   if ((IsNaN(quantum) != 0) || (quantum <= 0.0f))
     return((QuantumAny) 0UL);
+  if (quantum >= (Quantum) (QuantumRange-65536.0))
+    return(range);
+#else
+  if (quantum >= (Quantum) QuantumRange)
+    return(range);
 #endif
   value=(double) range*(double) quantum/(double) QuantumRange;
-  if (value >= 0x1p64)
-    return((QuantumAny) MagickULLConstant(18446744073709551615));
 #if defined(MAGICKCORE_HDRI_SUPPORT)
   value+=0.5;
 #endif
+  if (value >= (double) range)
+    return(range);
   return((QuantumAny) value);
 }