diff --git a/src/ImageSharp/Formats/Jxl/IO/JxlAnsHelper.cs b/src/ImageSharp/Formats/Jxl/IO/JxlAnsHelper.cs
new file mode 100644
index 0000000000..babbfe8fd5
--- /dev/null
+++ b/src/ImageSharp/Formats/Jxl/IO/JxlAnsHelper.cs
@@ -0,0 +1,25 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+using System.Buffers;
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+using static SixLabors.ImageSharp.Formats.Jxl.IO.JxlAnsConstants;
+
+namespace SixLabors.ImageSharp.Formats.Jxl.IO;
+
+internal static class JxlAnsHelper
+{
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static int GetPopulationCountPrecision(int logCount, int shift)
+    {
+        int r = Math.Min(logCount, shift - ((AnsLogTableSize - logCount) >> 1));
+
+        if (r < 0)
+        {
+            return 0;
+        }
+
+        return r;
+    }
+}