Force software decoding when hardware decoder does not support keyframe only mode but requested by user

Signed-off-by: gnattu <gnattuoc@me.com>

MediaBrowser.MediaEncoding/Encoder/MediaEncoder.cs

@@ -814,6 +814,22 @@ namespace MediaBrowser.MediaEncoding.Encoder
             var options = allowHwAccel ? _configurationManager.GetEncodingOptions() : new EncodingOptions();
             threads ??= _threads;
 
+            if (enableKeyFrameOnlyExtraction)
+            {
+                var supportsKeyFrameOnly = !allowHwAccel
+                                           || (string.Equals(options.HardwareAccelerationType, "nvenc", StringComparison.OrdinalIgnoreCase) && options.EnableEnhancedNvdecDecoder)
+                                           || (string.Equals(options.HardwareAccelerationType, "amf", StringComparison.OrdinalIgnoreCase) && OperatingSystem.IsWindows() && options.PreferSystemNativeHwDecoder)
+                                           || (string.Equals(options.HardwareAccelerationType, "qsv", StringComparison.OrdinalIgnoreCase) && options.PreferSystemNativeHwDecoder)
+                                           || string.Equals(options.HardwareAccelerationType, "vaapi", StringComparison.OrdinalIgnoreCase)
+                                           || string.Equals(options.HardwareAccelerationType, "videotoolbox", StringComparison.OrdinalIgnoreCase);
+                if (!supportsKeyFrameOnly)
+                {
+                    // Disable hardware acceleration when the hardware decoder does not support keyframe only mode.
+                    allowHwAccel = false;
+                    options = new EncodingOptions();
+                }
+            }
+
             // A new EncodingOptions instance must be used as to not disable HW acceleration for all of Jellyfin.
             // Additionally, we must set a few fields without defaults to prevent null pointer exceptions.
             if (!allowHwAccel)