Add failing tests

src/ImageSharp/ColorSpaces/Conversion/Implementation/Icc/Calculators/ClutCalculator.cs

@@ -14,6 +14,7 @@ internal class ClutCalculator : IVector4Calculator
     private readonly byte[] gridPointCount;
     private readonly int[] indexFactor;
     private readonly int nodeCount;
+    private readonly float[][] nodes;
 
     public ClutCalculator(IccClut clut)
     {
@@ -25,6 +26,7 @@ internal class ClutCalculator : IVector4Calculator
         this.gridPointCount = clut.GridPointCount;
         this.indexFactor = CalculateIndexFactor(clut.InputChannelCount, clut.GridPointCount);
         this.nodeCount = (int)Math.Pow(2, clut.InputChannelCount);
+        this.nodes = new float[this.nodeCount][];
     }
 
     public unsafe Vector4 Calculate(Vector4 value)
@@ -50,8 +52,7 @@ internal class ClutCalculator : IVector4Calculator
 
     private unsafe void Interpolate(float* values, int valueLength, float* result, int resultLength)
     {
-        float[][] nodes = new float[this.nodeCount][];
-        for (int i = 0; i < nodes.Length; i++)
+        for (int i = 0; i < this.nodes.Length; i++)
         {
             int index = 0;
             for (int j = 0; j < valueLength; j++)
@@ -61,7 +62,9 @@ internal class ClutCalculator : IVector4Calculator
                 index += (int)((this.indexFactor[j] * (position * fraction)) + 0.5f);
             }
 
-            nodes[i] = this.lut[index];
+            // TODO: The CMYK profile in our tests causes an out of range exception
+            // against 'lut'. Clamping the index leads to incorrect results.
+            this.nodes[i] = this.lut[index];
         }
 
         Span<float> factors = stackalloc float[this.nodeCount];
@@ -92,9 +95,9 @@ internal class ClutCalculator : IVector4Calculator
 
         for (int i = 0; i < resultLength; i++)
         {
-            for (int j = 0; j < nodes.Length; j++)
+            for (int j = 0; j < this.nodes.Length; j++)
             {
-                result[i] += nodes[j][i] * factors[j];
+                result[i] += this.nodes[j][i] * factors[j];
             }
         }
     }

tests/ImageSharp.Tests/Colorspaces/Icc/IccProfileConverterTests.cs

@@ -20,6 +20,7 @@ public class IccProfileConverterTests
     [WithFile(TestImages.Jpeg.ICC.WideRGB, PixelTypes.Rgb24)]
     [WithFile(TestImages.Jpeg.ICC.SRgb, PixelTypes.Rgb24)]
     [WithFile(TestImages.Jpeg.ICC.ProPhoto, PixelTypes.Rgb24)]
+    [WithFile(TestImages.Jpeg.ICC.CMYK, PixelTypes.Rgb24)]
     public void CanRoundTripProfile<TPixel>(TestImageProvider<TPixel> provider)
         where TPixel : unmanaged, IPixel<TPixel>
     {
@@ -45,6 +46,7 @@ public class IccProfileConverterTests
     [WithFile(TestImages.Jpeg.ICC.WideRGB, PixelTypes.Rgb24)]
     [WithFile(TestImages.Jpeg.ICC.SRgb, PixelTypes.Rgb24)]
     [WithFile(TestImages.Jpeg.ICC.ProPhoto, PixelTypes.Rgb24)]
+    [WithFile(TestImages.Jpeg.ICC.CMYK, PixelTypes.Rgb24)]
     public void CanConvertToSRGB<TPixel>(TestImageProvider<TPixel> provider)
         where TPixel : unmanaged, IPixel<TPixel>
     {

tests/ImageSharp.Tests/TestImages.cs

@@ -176,6 +176,7 @@ public static class TestImages
             public const string ProPhoto = "Jpg/icc-profiles/Momiji-ProPhoto-yes.jpg";
             public const string WideRGB = "Jpg/icc-profiles/Momiji-WideRGB-yes.jpg";
             public const string AppleRGB = "Jpg/icc-profiles/Momiji-AppleRGB-yes.jpg";
+            public const string CMYK = "Jpg/icc-profiles/issue-129.jpg";
         }
 
         public static class Progressive

tests/Images/Input/Jpg/icc-profiles/issue-129.jpg

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:e1728dd548d862ef3f960c82528716e0ad1b8eb0119a5eed4dfde51026d7bb74
+size 2903429