Override PhotometricInterpretation to RGB, if it's YCbCr and Jpeg compressed

src/ImageSharp/Common/Helpers/Numerics.cs

@@ -968,7 +968,7 @@ namespace SixLabors.ImageSharp
         /// Tells whether input value is outside of the given range.
         /// </summary>
         /// <param name="value">Value.</param>
-        /// <param name="min">Mininum value, inclusive.</param>
+        /// <param name="min">Minimum value, inclusive.</param>
         /// <param name="max">Maximum value, inclusive.</param>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static bool IsOutOfRange(int value, int min, int max)

src/ImageSharp/Formats/Tiff/Compression/Decompressors/JpegTiffCompression.cs

@@ -65,13 +65,11 @@ namespace SixLabors.ImageSharp.Formats.Tiff.Compression.Decompressors
                         jpegDecoder.ParseStream(stream, spectralConverterGray, CancellationToken.None);
 
                         // TODO: Should we pass through the CancellationToken from the tiff decoder?
-                        using var decompressedBuffer = spectralConverterGray.GetPixelBuffer(CancellationToken.None);
+                        using Buffer2D<L8> decompressedBuffer = spectralConverterGray.GetPixelBuffer(CancellationToken.None);
                         CopyImageBytesToBuffer(buffer, decompressedBuffer);
                         break;
                     }
 
-                    // If the PhotometricInterpretation is YCbCr we explicitly assume the JPEG data is in RGB color space.
-                    // There seems no other way to determine that the JPEG data is RGB colorspace (no APP14 marker, componentId's are not RGB).
                     case TiffPhotometricInterpretation.YCbCr:
                     case TiffPhotometricInterpretation.Rgb:
                     {
@@ -82,7 +80,7 @@ namespace SixLabors.ImageSharp.Formats.Tiff.Compression.Decompressors
                         jpegDecoder.ParseStream(stream, spectralConverter, CancellationToken.None);
 
                         // TODO: Should we pass through the CancellationToken from the tiff decoder?
-                        using var decompressedBuffer = spectralConverter.GetPixelBuffer(CancellationToken.None);
+                        using Buffer2D<Rgb24> decompressedBuffer = spectralConverter.GetPixelBuffer(CancellationToken.None);
                         CopyImageBytesToBuffer(buffer, decompressedBuffer);
                         break;
                     }

src/ImageSharp/Formats/Tiff/PhotometricInterpretation/YCbCrConverter.cs

@@ -19,16 +19,16 @@ namespace SixLabors.ImageSharp.Formats.Tiff.PhotometricInterpretation
 
         private static readonly Rational[] DefaultLuma =
         {
-            new Rational(299, 1000),
-            new Rational(587, 1000),
-            new Rational(114, 1000)
+            new(299, 1000),
+            new(587, 1000),
+            new(114, 1000)
         };
 
         private static readonly Rational[] DefaultReferenceBlackWhite =
         {
-            new Rational(0, 1), new Rational(255, 1),
-            new Rational(128, 1), new Rational(255, 1),
-            new Rational(128, 1), new Rational(255, 1)
+            new(0, 1), new(255, 1),
+            new(128, 1), new(255, 1),
+            new(128, 1), new(255, 1)
         };
 
         public YCbCrConverter(Rational[] referenceBlackAndWhite, Rational[] coefficients)

src/ImageSharp/Formats/Tiff/TiffDecoderCore.cs

@@ -228,7 +228,7 @@ namespace SixLabors.ImageSharp.Formats.Tiff
         /// <typeparam name="TPixel">The pixel format.</typeparam>
         /// <param name="tags">The IFD tags.</param>
         /// <param name="cancellationToken">The token to monitor cancellation.</param>
-        /// <returns> The tiff frame. </returns>
+        /// <returns>The tiff frame.</returns>
         private ImageFrame<TPixel> DecodeFrame<TPixel>(ExifProfile tags, CancellationToken cancellationToken)
             where TPixel : unmanaged, IPixel<TPixel>
         {

src/ImageSharp/Formats/Tiff/TiffDecoderOptionsParser.cs

@@ -459,6 +459,13 @@ namespace SixLabors.ImageSharp.Formats.Tiff
                 case TiffCompression.Jpeg:
                 {
                     options.CompressionType = TiffDecoderCompressionType.Jpeg;
+
+                    if (options.PhotometricInterpretation is TiffPhotometricInterpretation.YCbCr && options.JpegTables is null)
+                    {
+                        // Note: Setting PhotometricInterpretation to RGB here, since the jpeg decoder will handle the conversion of the pixel data.
+                        options.PhotometricInterpretation = TiffPhotometricInterpretation.Rgb;
+                    }
+
                     break;
                 }
 

tests/ImageSharp.Tests/Formats/Tiff/TiffDecoderTests.cs

@@ -642,6 +642,7 @@ namespace SixLabors.ImageSharp.Tests.Formats.Tiff
         [WithFile(RgbJpegCompressed, PixelTypes.Rgba32)]
         [WithFile(RgbWithStripsJpegCompressed, PixelTypes.Rgba32)]
         [WithFile(YCbCrJpegCompressed, PixelTypes.Rgba32)]
+        [WithFile(YCbCrJpegCompressed2, PixelTypes.Rgba32)]
         [WithFile(RgbJpegCompressedNoJpegTable, PixelTypes.Rgba32)]
         [WithFile(GrayscaleJpegCompressed, PixelTypes.Rgba32)]
         public void TiffDecoder_CanDecode_JpegCompressed<TPixel>(TestImageProvider<TPixel> provider)

tests/ImageSharp.Tests/TestImages.cs

@@ -834,6 +834,7 @@ namespace SixLabors.ImageSharp.Tests
             public const string RgbYCbCr888Contiguoush2v2 = "Tiff/rgb-ycbcr-contig-08_h2v2.tiff";
             public const string RgbYCbCr888Contiguoush4v4 = "Tiff/rgb-ycbcr-contig-08_h4v4.tiff";
             public const string YCbCrJpegCompressed = "Tiff/ycbcr_jpegcompressed.tiff";
+            public const string YCbCrJpegCompressed2 = "Tiff/ycbcr_jpegcompressed2.tiff";
             public const string FlowerRgb444Contiguous = "Tiff/flower-rgb-contig-04.tiff";
             public const string FlowerRgb444Planar = "Tiff/flower-rgb-planar-04.tiff";
             public const string FlowerRgb222Contiguous = "Tiff/flower-rgb-contig-02.tiff";

tests/Images/Input/Tiff/ycbcr_jpegcompressed2.tiff

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:533f92b6a45c2de4dc0f3cdb8debf45dcfe84790cfa652404b2f44e15f06e44f
+size 38816