Use enums for encoding options (#12561)

MediaBrowser.Model/Entities/TonemappingMode.cs

@@ -0,0 +1,34 @@
+#pragma warning disable SA1300 // Lowercase required for backwards compat.
+
+namespace MediaBrowser.Model.Entities;
+
+/// <summary>
+/// Enum containing tonemapping modes.
+/// </summary>
+public enum TonemappingMode
+{
+    /// <summary>
+    /// Auto.
+    /// </summary>
+    auto = 0,
+
+    /// <summary>
+    /// Max.
+    /// </summary>
+    max = 1,
+
+    /// <summary>
+    /// RGB.
+    /// </summary>
+    rgb = 2,
+
+    /// <summary>
+    /// Lum.
+    /// </summary>
+    lum = 3,
+
+    /// <summary>
+    /// ITP.
+    /// </summary>
+    itp = 4
+}