Always set YcbcrSubSampling to 1:1 for TiffCompression.Jpeg, fixes issue #2679

Author: brianpopow

src/ImageSharp/Formats/Tiff/TiffDecoderOptionsParser.cs

@@ -620,15 +620,33 @@ private static void ParseCompression(this TiffDecoderCore options, TiffCompressi
                 }
 
                 options.CompressionType = TiffDecoderCompressionType.OldJpeg;
-                AdjustOptionsYCbCrJpegCompression(options);
+                if (options.PhotometricInterpretation is TiffPhotometricInterpretation.YCbCr)
+                {
+                    // Note: Setting PhotometricInterpretation and color type to RGB here, since the jpeg decoder will handle the conversion of the pixel data.
+                    options.PhotometricInterpretation = TiffPhotometricInterpretation.Rgb;
+                    options.ColorType = TiffColorType.Rgb;
+                }
 
                 break;
             }
 
             case TiffCompression.Jpeg:
             {
                 options.CompressionType = TiffDecoderCompressionType.Jpeg;
-                AdjustOptionsYCbCrJpegCompression(options);
+                if (options.PhotometricInterpretation is TiffPhotometricInterpretation.YCbCr && options.JpegTables is null)
+                {
+                    // Note: Setting PhotometricInterpretation and color type to RGB here, since the jpeg decoder will handle the conversion of the pixel data.
+                    options.PhotometricInterpretation = TiffPhotometricInterpretation.Rgb;
+                    options.ColorType = TiffColorType.Rgb;
+                }
+
+                // Some tiff encoder set this to values different from [1, 1]. The jpeg decoder already handles this,
+                // so we set this always to [1, 1], see: https://github.com/SixLabors/ImageSharp/issues/2679
+                if (options.PhotometricInterpretation is TiffPhotometricInterpretation.YCbCr)
+                {
+                    options.YcbcrSubSampling[0] = 1;
+                    options.YcbcrSubSampling[1] = 1;
+                }
 
                 break;
             }
@@ -647,24 +665,6 @@ private static void ParseCompression(this TiffDecoderCore options, TiffCompressi
         }
     }
 
-    private static void AdjustOptionsYCbCrJpegCompression(TiffDecoderCore options)
-    {
-        if (options.PhotometricInterpretation is TiffPhotometricInterpretation.YCbCr)
-        {
-            // Note: Setting PhotometricInterpretation and color type to RGB here, since the jpeg decoder will handle the conversion of the pixel data.
-            options.PhotometricInterpretation = TiffPhotometricInterpretation.Rgb;
-            options.ColorType = TiffColorType.Rgb;
-        }
-
-        if (options.PhotometricInterpretation is TiffPhotometricInterpretation.YCbCr)
-        {
-            // Some tiff encoder set this to values different from [1, 1]. The jpeg decoder already handles this,
-            // so we set this always to [1, 1], see: https://github.com/SixLabors/ImageSharp/issues/2679
-            options.YcbcrSubSampling[0] = 1;
-            options.YcbcrSubSampling[1] = 1;
-        }
-    }
-
     private static bool IsBiColorCompression(TiffCompression? compression)
     {
         if (compression is TiffCompression.Ccitt1D or TiffCompression.CcittGroup3Fax or