Merge pull request #678 from carbon/nulls

Improve CQ7

src/ImageSharp.Drawing/Processing/Processors/Text/DrawTextProcessor.cs

@@ -37,9 +37,10 @@ namespace SixLabors.ImageSharp.Processing.Processors.Text
         {
             Guard.NotNull(text, nameof(text));
             Guard.NotNull(font, nameof(font));
-            if (brush == null && pen == null)
+
+            if (brush is null && pen is null)
             {
-                throw new ArgumentNullException($"at least one of {nameof(brush)} or {nameof(pen)} must not be null");
+                throw new ArgumentNullException($"Expected a {nameof(brush)} or {nameof(pen)}. Both were null");
             }
 
             this.Options = options;

src/ImageSharp/Common/Helpers/DebugGuard.cs

@@ -24,7 +24,7 @@ namespace SixLabors.ImageSharp
         public static void NotNull<T>(T value, string parameterName)
             where T : class
         {
-            if (value == null)
+            if (value is null)
             {
                 throw new ArgumentNullException(parameterName);
             }

src/ImageSharp/Common/Helpers/Guard.cs

@@ -22,7 +22,7 @@ namespace SixLabors.ImageSharp
         public static void NotNull<T>(T value, string parameterName)
             where T : class
         {
-            if (value == null)
+            if (value is null)
             {
                 throw new ArgumentNullException(parameterName);
             }
@@ -37,7 +37,7 @@ namespace SixLabors.ImageSharp
         /// <exception cref="ArgumentException"><paramref name="value"/> is empty or contains only blanks.</exception>
         public static void NotNullOrWhiteSpace(string value, string parameterName)
         {
-            if (value == null)
+            if (value is null)
             {
                 throw new ArgumentNullException(parameterName);
             }
@@ -58,7 +58,7 @@ namespace SixLabors.ImageSharp
         /// <exception cref="ArgumentException"><paramref name="value"/> is empty.</exception>
         public static void NotNullOrEmpty<T>(ICollection<T> value, string parameterName)
         {
-            if (value == null)
+            if (value is null)
             {
                 throw new ArgumentNullException(parameterName);
             }

src/ImageSharp/Formats/Bmp/BmpDecoder.cs

@@ -25,7 +25,6 @@ namespace SixLabors.ImageSharp.Formats.Bmp
     {
         /// <inheritdoc/>
         public Image<TPixel> Decode<TPixel>(Configuration configuration, Stream stream)
-
             where TPixel : struct, IPixel<TPixel>
         {
             Guard.NotNull(stream, nameof(stream));

src/ImageSharp/Formats/Gif/GifDecoderCore.cs

@@ -377,7 +377,7 @@ namespace SixLabors.ImageSharp.Formats.Gif
             ImageFrame<TPixel> currentFrame = null;
             ImageFrame<TPixel> imageFrame;
 
-            if (previousFrame == null)
+            if (previousFrame is null)
             {
                 // This initializes the image to become fully transparent because the alpha channel is zero.
                 image = new Image<TPixel>(this.configuration, imageWidth, imageHeight, this.metaData);
@@ -485,7 +485,7 @@ namespace SixLabors.ImageSharp.Formats.Gif
         private void RestoreToBackground<TPixel>(ImageFrame<TPixel> frame)
             where TPixel : struct, IPixel<TPixel>
         {
-            if (this.restoreArea == null)
+            if (this.restoreArea is null)
             {
                 return;
             }

src/ImageSharp/Formats/Gif/GifEncoderCore.cs

@@ -159,7 +159,7 @@ namespace SixLabors.ImageSharp.Formats.Gif
         {
             foreach (ImageFrame<TPixel> frame in image.Frames)
             {
-                if (quantized == null)
+                if (quantized is null)
                 {
                     quantized = this.quantizer.CreateFrameQuantizer<TPixel>().QuantizeFrame(frame);
                 }

src/ImageSharp/Formats/Gif/LzwDecoder.cs

@@ -56,9 +56,7 @@ namespace SixLabors.ImageSharp.Formats.Gif
         /// <exception cref="System.ArgumentNullException"><paramref name="stream"/> is null.</exception>
         public LzwDecoder(MemoryAllocator memoryAllocator, Stream stream)
         {
-            Guard.NotNull(stream, nameof(stream));
+            this.stream = stream ?? throw new ArgumentNullException(nameof(stream));
-
-            this.stream = stream;
 
             this.prefix = memoryAllocator.Allocate<int>(MaxStackSize, AllocationOptions.Clean);
             this.suffix = memoryAllocator.Allocate<int>(MaxStackSize, AllocationOptions.Clean);

src/ImageSharp/Formats/Jpeg/Components/Decoder/ColorConverters/JpegColorConverter.cs

@@ -44,7 +44,8 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Components.Decoder.ColorConverters
         public static JpegColorConverter GetConverter(JpegColorSpace colorSpace)
         {
             JpegColorConverter converter = Converters.FirstOrDefault(c => c.ColorSpace == colorSpace);
-            if (converter == null)
+
+            if (converter is null)
             {
                 throw new Exception($"Could not find any converter for JpegColorSpace {colorSpace}!");
             }

src/ImageSharp/Formats/Jpeg/Components/GenericBlock8x8.cs

@@ -58,13 +58,14 @@ namespace SixLabors.ImageSharp.Formats.Jpeg.Components
         public void LoadAndStretchEdges<TPixel>(IPixelSource<TPixel> source, int sourceX, int sourceY)
             where TPixel : struct, IPixel<TPixel>
         {
-            var buffer = source.PixelBuffer as Buffer2D<T>;
+            if (source.PixelBuffer is Buffer2D<T> buffer)
-            if (buffer == null)
+            {
+                this.LoadAndStretchEdges(buffer, sourceX, sourceY);
+            }
+            else
             {
                 throw new InvalidOperationException("LoadAndStretchEdges<TPixels>() is only valid for TPixel == T !");
             }
-
-            this.LoadAndStretchEdges(buffer, sourceX, sourceY);
         }
 
         /// <summary>

src/ImageSharp/Formats/Jpeg/JpegDecoderCore.cs

@@ -538,7 +538,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
             if (ProfileResolver.IsProfile(profile, ProfileResolver.ExifMarker))
             {
                 this.isExif = true;
-                if (this.exifData == null)
+                if (this.exifData is null)
                 {
                     // The first 6 bytes (Exif00) will be skipped, because this is Jpeg specific
                     this.exifData = profile.Skip(Exif00).ToArray();
@@ -575,7 +575,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
                 byte[] profile = new byte[remaining];
                 this.InputStream.Read(profile, 0, remaining);
 
-                if (this.iccData == null)
+                if (this.iccData is null)
                 {
                     this.iccData = profile;
                 }

src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs

@@ -550,7 +550,8 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
         private void WriteDefineHuffmanTables(int componentCount)
         {
             // Table identifiers.
-            byte[] headers = { 0x00, 0x10, 0x01, 0x11 };
+            Span<byte> headers = stackalloc byte[] { 0x00, 0x10, 0x01, 0x11 };
+
             int markerlen = 2;
             HuffmanSpec[] specs = HuffmanSpec.TheHuffmanSpecs;
 
@@ -628,7 +629,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
 
             byte[] data = exifProfile?.ToByteArray();
 
-            if (data == null || data.Length == 0)
+            if (data is null || data.Length == 0)
             {
                 return;
             }
@@ -687,7 +688,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
         /// </exception>
         private void WriteIccProfile(IccProfile iccProfile)
         {
-            if (iccProfile == null)
+            if (iccProfile is null)
             {
                 return;
             }
@@ -698,7 +699,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg
 
             byte[] data = iccProfile.ToByteArray();
 
-            if (data == null || data.Length == 0)
+            if (data is null || data.Length == 0)
             {
                 return;
             }

src/ImageSharp/Formats/Png/PngDecoderCore.cs

@@ -239,7 +239,7 @@ namespace SixLabors.ImageSharp.Formats.Png
                                     this.ReadPhysicalChunk(metadata, chunk.Data.GetSpan());
                                     break;
                                 case PngChunkType.Data:
-                                    if (image == null)
+                                    if (image is null)
                                     {
                                         this.InitializeImage(metadata, out image);
                                     }
@@ -283,7 +283,7 @@ namespace SixLabors.ImageSharp.Formats.Png
                     }
                 }
 
-                if (image == null)
+                if (image is null)
                 {
                     throw new ImageFormatException("PNG Image does not contain a data chunk");
                 }

src/ImageSharp/Formats/Png/Zlib/ZlibInflateStream.cs

@@ -88,7 +88,7 @@ namespace SixLabors.ImageSharp.Formats.Png.Zlib
         public void AllocateNewBytes(int bytes)
         {
             this.currentDataRemaining = bytes;
-            if (this.compressedStream == null)
+            if (this.compressedStream is null)
             {
                 this.InitializeInflateStream();
             }

src/ImageSharp/Image.Decode.cs

@@ -70,7 +70,7 @@ namespace SixLabors.ImageSharp
             where TPixel : struct, IPixel<TPixel>
         {
             IImageDecoder decoder = DiscoverDecoder(stream, config, out IImageFormat format);
-            if (decoder == null)
+            if (decoder is null)
             {
                 return (null, null);
             }

src/ImageSharp/ImageExtensions.cs

@@ -32,7 +32,7 @@ namespace SixLabors.ImageSharp
 
             string ext = Path.GetExtension(filePath);
             IImageFormat format = source.GetConfiguration().ImageFormatsManager.FindFormatByFileExtension(ext);
-            if (format == null)
+            if (format is null)
             {
                 var sb = new StringBuilder();
                 sb.AppendLine($"Can't find a format that is associated with the file extention '{ext}'. Registered formats with there extensions include:");
@@ -46,7 +46,7 @@ namespace SixLabors.ImageSharp
 
             IImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
 
-            if (encoder == null)
+            if (encoder is null)
             {
                 var sb = new StringBuilder();
                 sb.AppendLine($"Can't find encoder for file extention '{ext}' using image format '{format.Name}'. Registered encoders include:");
@@ -94,7 +94,7 @@ namespace SixLabors.ImageSharp
             Guard.NotNull(format, nameof(format));
             IImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
 
-            if (encoder == null)
+            if (encoder is null)
             {
                 var sb = new StringBuilder();
                 sb.AppendLine("Can't find encoder for provided mime type. Available encoded:");

src/ImageSharp/ImageFrameCollection.cs

@@ -7,7 +7,6 @@ using System.Collections.Generic;
 using SixLabors.ImageSharp.Advanced;
 using SixLabors.ImageSharp.Memory;
 using SixLabors.ImageSharp.PixelFormats;
-using SixLabors.Memory;
 
 namespace SixLabors.ImageSharp
 {
@@ -23,9 +22,7 @@ namespace SixLabors.ImageSharp
 
         internal ImageFrameCollection(Image<TPixel> parent, int width, int height, TPixel backgroundColor)
         {
-            Guard.NotNull(parent, nameof(parent));
+            this.parent = parent ?? throw new ArgumentNullException(nameof(parent));
-
-            this.parent = parent;
 
             // Frames are already cloned within the caller
             this.frames.Add(new ImageFrame<TPixel>(parent.GetConfiguration(), width, height, backgroundColor));
@@ -33,9 +30,7 @@ namespace SixLabors.ImageSharp
 
         internal ImageFrameCollection(Image<TPixel> parent, int width, int height, MemorySource<TPixel> memorySource)
         {
-            Guard.NotNull(parent, nameof(parent));
+            this.parent = parent ?? throw new ArgumentNullException(nameof(parent));
-
-            this.parent = parent;
 
             // Frames are already cloned within the caller
             this.frames.Add(new ImageFrame<TPixel>(parent.GetConfiguration(), width, height, memorySource));

src/ImageSharp/MetaData/Profiles/Exif/ExifProfile.cs

@@ -128,7 +128,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
                 return null;
             }
 
-            if (this.data == null || this.data.Length < (this.thumbnailOffset + this.thumbnailLength))
+            if (this.data is null || this.data.Length < (this.thumbnailOffset + this.thumbnailLength))
             {
                 return null;
             }
@@ -235,7 +235,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         /// <returns>The <see cref="T:byte[]"/></returns>
         public byte[] ToByteArray()
         {
-            if (this.values == null)
+            if (this.values is null)
             {
                 return this.data;
             }
@@ -262,7 +262,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         private void SyncResolution(ExifTag tag, double resolution)
         {
             ExifValue value = this.GetValue(tag);
-            if (value == null)
+
+            if (value is null)
             {
                 return;
             }
@@ -283,7 +284,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
                 return;
             }
 
-            if (this.data == null)
+            if (this.data is null)
             {
                 this.values = new List<ExifValue>();
                 return;

src/ImageSharp/MetaData/Profiles/Exif/ExifReader.cs

@@ -76,7 +76,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         {
             var values = new List<ExifValue>();
 
-            if (this.ReadString(2) == "II")
+            // II == 0x4949
+            if (this.ReadUInt16() == 0x4949)
             {
                 this.endianness = Endianness.LittleEndian;
             }
@@ -202,7 +203,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
 
         private object ConvertValue(ExifDataType dataType, ReadOnlySpan<byte> buffer, uint numberOfComponents)
         {
-            if (buffer == null || buffer.Length == 0)
+            if (buffer.Length == 0)
             {
                 return null;
             }

src/ImageSharp/MetaData/Profiles/Exif/ExifTagDescriptionAttribute.cs

@@ -12,8 +12,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
     [AttributeUsage(AttributeTargets.Field, AllowMultiple = true)]
     internal sealed class ExifTagDescriptionAttribute : Attribute
     {
-        private object value;
+        private readonly object value;
-        private string description;
+        private readonly string description;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="ExifTagDescriptionAttribute"/> class.
@@ -37,7 +37,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         public static string GetDescription(ExifTag tag, object value)
         {
             FieldInfo field = tag.GetType().GetTypeInfo().GetDeclaredField(tag.ToString());
-            if (field == null)
+
+            if (field is null)
             {
                 return null;
             }

src/ImageSharp/MetaData/Profiles/Exif/ExifValue.cs

@@ -80,7 +80,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         {
             get
             {
-                if (this.Value == null)
+                if (this.Value is null)
                 {
                     return false;
                 }
@@ -101,7 +101,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         {
             get
             {
-                if (this.Value == null)
+                if (this.Value is null)
                 {
                     return 4;
                 }
@@ -213,7 +213,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         /// <inheritdoc/>
         public override string ToString()
         {
-            if (this.Value == null)
+            if (this.Value is null)
             {
                 return null;
             }
@@ -589,7 +589,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
                 type = type.GetElementType();
             }
 
-            if (type == null || type == typeof(ushort))
+            if (type is null || type == typeof(ushort))
             {
                 return new ExifValue(tag, ExifDataType.Short, value, isArray);
             }
@@ -616,7 +616,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         /// </exception>
         private void CheckValue(object value)
         {
-            if (value == null)
+            if (value is null)
             {
                 return;
             }

src/ImageSharp/MetaData/Profiles/Exif/ExifWriter.cs

@@ -20,9 +20,9 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Exif
         private ExifParts allowedParts;
         private IList<ExifValue> values;
         private List<int> dataOffsets;
-        private List<int> ifdIndexes;
+        private readonly List<int> ifdIndexes;
-        private List<int> exifIndexes;
+        private readonly List<int> exifIndexes;
-        private List<int> gpsIndexes;
+        private readonly List<int> gpsIndexes;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="ExifWriter"/> class.

src/ImageSharp/MetaData/Profiles/ICC/Curves/IccCurveSegment.cs

@@ -27,7 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public virtual bool Equals(IccCurveSegment other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }
@@ -40,4 +40,4 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
             return this.Signature == other.Signature;
         }
     }
-}
+}

src/ImageSharp/MetaData/Profiles/ICC/Curves/IccOneDimensionalCurve.cs

@@ -41,7 +41,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc />
         public bool Equals(IccOneDimensionalCurve other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/Curves/IccResponseCurve.cs

@@ -49,7 +49,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccResponseCurve other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/DataReader/IccDataReader.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.Text;
 
 namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
@@ -28,8 +29,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <param name="data">The data to read</param>
         public IccDataReader(byte[] data)
         {
-            Guard.NotNull(data, nameof(data));
+            this.data = data ?? throw new ArgumentNullException(nameof(data));
-            this.data = data;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/DataWriter/IccDataWriter.Primitives.cs

@@ -199,7 +199,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
 
             Guard.MustBeGreaterThan(length, 0, nameof(length));
 
-            if (value == null)
+            if (value is null)
             {
                 value = string.Empty;
             }

src/ImageSharp/MetaData/Profiles/ICC/DataWriter/IccDataWriter.TagDataEntry.cs

@@ -901,7 +901,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         {
             int size, count = 0;
 
-            if (value.Ascii == null)
+            if (value.Ascii is null)
             {
                 count += this.WriteUInt32(0);
             }
@@ -914,7 +914,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
                 this.dataStream.Position += size;
             }
 
-            if (value.Unicode == null)
+            if (value.Unicode is null)
             {
                 count += this.WriteUInt32(0);
                 count += this.WriteUInt32(0);
@@ -929,7 +929,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
                 this.dataStream.Position += size;
             }
 
-            if (value.ScriptCode == null)
+            if (value.ScriptCode is null)
             {
                 count += this.WriteUInt16(0);
                 count += this.WriteByte(0);

src/ImageSharp/MetaData/Profiles/ICC/IccProfile.cs

@@ -18,7 +18,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <summary>
         /// The byte array to read the ICC profile from
         /// </summary>
-        private byte[] data;
+        private readonly byte[] data;
 
         /// <summary>
         /// The backing file for the <see cref="Entries"/> property
@@ -200,7 +200,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
                 return;
             }
 
-            if (this.data == null)
+            if (this.data is null)
             {
                 this.header = new IccProfileHeader();
                 return;
@@ -217,7 +217,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
                 return;
             }
 
-            if (this.data == null)
+            if (this.data is null)
             {
                 this.entries = new List<IccTagDataEntry>();
                 return;

src/ImageSharp/MetaData/Profiles/ICC/IccTagDataEntry.cs

@@ -50,7 +50,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public virtual bool Equals(IccTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/MultiProcessElements/IccClutProcessElement.cs

@@ -17,8 +17,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccClutProcessElement(IccClut clutValue)
             : base(IccMultiProcessElementSignature.Clut, clutValue?.InputChannelCount ?? 1, clutValue?.OutputChannelCount ?? 1)
         {
-            Guard.NotNull(clutValue, nameof(clutValue));
+            this.ClutValue = clutValue ?? throw new ArgumentNullException(nameof(clutValue));
-            this.ClutValue = clutValue;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/MultiProcessElements/IccCurveSetProcessElement.cs

@@ -18,8 +18,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccCurveSetProcessElement(IccOneDimensionalCurve[] curves)
             : base(IccMultiProcessElementSignature.CurveSet, curves?.Length ?? 1, curves?.Length ?? 1)
         {
-            Guard.NotNull(curves, nameof(curves));
+            this.Curves = curves ?? throw new ArgumentNullException(nameof(curves));
-            this.Curves = curves;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/MultiProcessElements/IccMultiProcessElement.cs

@@ -44,7 +44,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public virtual bool Equals(IccMultiProcessElement other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccChromaticityTagDataEntry.cs

@@ -60,7 +60,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
             this.ChannelValues = channelValues;
 
             int channelLength = channelValues[0].Length;
-            bool channelsNotSame = channelValues.Any(t => t == null || t.Length != channelLength);
+            bool channelsNotSame = channelValues.Any(t => t is null || t.Length != channelLength);
             Guard.IsFalse(channelsNotSame, nameof(channelValues), "The number of values per channel is not the same for all channels");
         }
 

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccColorantOrderTagDataEntry.cs

@@ -48,7 +48,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccColorantOrderTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccColorantTableTagDataEntry.cs

@@ -50,7 +50,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccColorantTableTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccCrdInfoTagDataEntry.cs

@@ -94,7 +94,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccCrdInfoTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccCurveTagDataEntry.cs

@@ -96,7 +96,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccCurveTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccDataTagDataEntry.cs

@@ -42,8 +42,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccDataTagDataEntry(byte[] data, bool isAscii, IccProfileTag tagSignature)
             : base(IccTypeSignature.Data, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentException(nameof(data));
-            this.Data = data;
             this.IsAscii = isAscii;
         }
 
@@ -72,7 +71,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccDataTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccDateTimeTagDataEntry.cs

@@ -44,7 +44,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccDateTimeTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccFix16ArrayTagDataEntry.cs

@@ -27,8 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccFix16ArrayTagDataEntry(float[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.S15Fixed16Array, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>
@@ -45,7 +44,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccFix16ArrayTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccLut16TagDataEntry.cs

@@ -117,7 +117,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccLut16TagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccLut8TagDataEntry.cs

@@ -120,7 +120,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccLut8TagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccLutAToBTagDataEntry.cs

@@ -153,7 +153,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccLutAToBTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }
@@ -200,8 +200,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
 
         private bool EqualsCurve(IccTagDataEntry[] thisCurves, IccTagDataEntry[] entryCurves)
         {
-            bool thisNull = thisCurves == null;
+            bool thisNull = thisCurves is null;
-            bool entryNull = entryCurves == null;
+            bool entryNull = entryCurves is null;
 
             if (thisNull && entryNull)
             {
@@ -271,7 +271,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
 
         private Vector3? CreateMatrix3x1(float[] matrix)
         {
-            if (matrix == null)
+            if (matrix is null)
             {
                 return null;
             }
@@ -281,7 +281,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
 
         private Matrix4x4? CreateMatrix3x3(float[,] matrix)
         {
-            if (matrix == null)
+            if (matrix is null)
             {
                 return null;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccLutBToATagDataEntry.cs

@@ -153,7 +153,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccLutBToATagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }
@@ -200,8 +200,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
 
         private bool EqualsCurve(IccTagDataEntry[] thisCurves, IccTagDataEntry[] entryCurves)
         {
-            bool thisNull = thisCurves == null;
+            bool thisNull = thisCurves is null;
-            bool entryNull = entryCurves == null;
+            bool entryNull = entryCurves is null;
 
             if (thisNull && entryNull)
             {
@@ -271,7 +271,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
 
         private Vector3? CreateMatrix3x1(float[] matrix)
         {
-            if (matrix == null)
+            if (matrix is null)
             {
                 return null;
             }
@@ -281,7 +281,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
 
         private Matrix4x4? CreateMatrix3x3(float[,] matrix)
         {
-            if (matrix == null)
+            if (matrix is null)
             {
                 return null;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccMeasurementTagDataEntry.cs

@@ -79,7 +79,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccMeasurementTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccMultiLocalizedUnicodeTagDataEntry.cs

@@ -29,8 +29,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccMultiLocalizedUnicodeTagDataEntry(IccLocalizedString[] texts, IccProfileTag tagSignature)
             : base(IccTypeSignature.MultiLocalizedUnicode, tagSignature)
         {
-            Guard.NotNull(texts, nameof(texts));
+            this.Texts = texts ?? throw new ArgumentNullException(nameof(texts));
-            this.Texts = texts;
         }
 
         /// <summary>
@@ -47,7 +46,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccMultiLocalizedUnicodeTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccMultiProcessElementsTagDataEntry.cs

@@ -65,7 +65,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccMultiProcessElementsTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccProfileSequenceDescTagDataEntry.cs

@@ -30,8 +30,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccProfileSequenceDescTagDataEntry(IccProfileDescription[] descriptions, IccProfileTag tagSignature)
             : base(IccTypeSignature.ProfileSequenceDesc, tagSignature)
         {
-            Guard.NotNull(descriptions, nameof(descriptions));
+            this.Descriptions = descriptions ?? throw new ArgumentNullException(nameof(descriptions));
-            this.Descriptions = descriptions;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccProfileSequenceIdentifierTagDataEntry.cs

@@ -28,8 +28,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccProfileSequenceIdentifierTagDataEntry(IccProfileSequenceIdentifier[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.ProfileSequenceIdentifier, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccScreeningTagDataEntry.cs

@@ -30,10 +30,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccScreeningTagDataEntry(IccScreeningFlag flags, IccScreeningChannel[] channels, IccProfileTag tagSignature)
             : base(IccTypeSignature.Screening, tagSignature)
         {
-            Guard.NotNull(channels, nameof(channels));
-
             this.Flags = flags;
-            this.Channels = channels;
+            this.Channels = channels ?? throw new ArgumentNullException(nameof(channels));
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccSignatureTagDataEntry.cs

@@ -28,12 +28,11 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccSignatureTagDataEntry(string signatureData, IccProfileTag tagSignature)
             : base(IccTypeSignature.Signature, tagSignature)
         {
-            Guard.NotNull(signatureData, nameof(signatureData));
+            this.SignatureData = signatureData ?? throw new ArgumentNullException(nameof(signatureData));
-            this.SignatureData = signatureData;
         }
 
         /// <summary>
-        /// Gets the Signature
+        /// Gets the signature data
         /// </summary>
         public string SignatureData { get; }
 

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccTextDescriptionTagDataEntry.cs

@@ -76,7 +76,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <returns>The converted entry</returns>
         public static explicit operator IccMultiLocalizedUnicodeTagDataEntry(IccTextDescriptionTagDataEntry textEntry)
         {
-            if (textEntry == null)
+            if (textEntry is null)
             {
                 return null;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccTextTagDataEntry.cs

@@ -27,8 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccTextTagDataEntry(string text, IccProfileTag tagSignature)
             : base(IccTypeSignature.Text, tagSignature)
         {
-            Guard.NotNull(text, nameof(text));
+            this.Text = text ?? throw new ArgumentNullException(nameof(text));
-            this.Text = text;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccUFix16ArrayTagDataEntry.cs

@@ -27,8 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccUFix16ArrayTagDataEntry(float[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.U16Fixed16Array, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccUInt16ArrayTagDataEntry.cs

@@ -27,8 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccUInt16ArrayTagDataEntry(ushort[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.UInt16Array, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccUInt32ArrayTagDataEntry.cs

@@ -27,8 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccUInt32ArrayTagDataEntry(uint[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.UInt32Array, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>
@@ -45,7 +44,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccUInt32ArrayTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccUInt64ArrayTagDataEntry.cs

@@ -28,8 +28,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccUInt64ArrayTagDataEntry(ulong[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.UInt64Array, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>
@@ -46,7 +45,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccUInt64ArrayTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccUInt8ArrayTagDataEntry.cs

@@ -27,8 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccUInt8ArrayTagDataEntry(byte[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.UInt8Array, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>
@@ -45,7 +44,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccUInt8ArrayTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccUcrBgTagDataEntry.cs

@@ -32,13 +32,9 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccUcrBgTagDataEntry(ushort[] ucrCurve, ushort[] bgCurve, string description, IccProfileTag tagSignature)
             : base(IccTypeSignature.UcrBg, tagSignature)
         {
-            Guard.NotNull(ucrCurve, nameof(ucrCurve));
+            this.UcrCurve = ucrCurve ?? throw new ArgumentNullException(nameof(ucrCurve));
-            Guard.NotNull(bgCurve, nameof(bgCurve));
+            this.BgCurve = bgCurve ?? throw new ArgumentNullException(nameof(bgCurve));
-            Guard.NotNull(description, nameof(description));
+            this.Description = description ?? throw new ArgumentNullException(nameof(description));
-
-            this.UcrCurve = ucrCurve;
-            this.BgCurve = bgCurve;
-            this.Description = description;
         }
 
         /// <summary>
@@ -65,7 +61,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccUcrBgTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccUnknownTagDataEntry.cs

@@ -27,8 +27,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccUnknownTagDataEntry(byte[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.Unknown, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>
@@ -45,7 +44,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccUnknownTagDataEntry other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/TagDataEntries/IccXyzTagDataEntry.cs

@@ -28,8 +28,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         public IccXyzTagDataEntry(Vector3[] data, IccProfileTag tagSignature)
             : base(IccTypeSignature.Xyz, tagSignature)
         {
-            Guard.NotNull(data, nameof(data));
+            this.Data = data ?? throw new ArgumentNullException(nameof(data));
-            this.Data = data;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/Various/IccClut.cs

@@ -116,7 +116,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <inheritdoc/>
         public bool Equals(IccClut other)
         {
-            if (other == null)
+            if (other is null)
             {
                 return false;
             }

src/ImageSharp/MetaData/Profiles/ICC/Various/IccColorantTableEntry.cs

@@ -28,9 +28,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <param name="pcs3">Third PCS value</param>
         public IccColorantTableEntry(string name, ushort pcs1, ushort pcs2, ushort pcs3)
         {
-            Guard.NotNull(name, nameof(name));
+            this.Name = name ?? throw new ArgumentNullException(nameof(name));
-
-            this.Name = name;
             this.Pcs1 = pcs1;
             this.Pcs2 = pcs2;
             this.Pcs3 = pcs3;

src/ImageSharp/MetaData/Profiles/ICC/Various/IccLocalizedString.cs

@@ -29,11 +29,8 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <param name="text">The text value of this string</param>
         public IccLocalizedString(CultureInfo culture, string text)
         {
-            Guard.NotNull(culture, nameof(culture));
+            this.Culture = culture ?? throw new ArgumentNullException(nameof(culture));
-            Guard.NotNull(text, nameof(text));
+            this.Text = text ?? throw new ArgumentNullException(nameof(text));
-
-            this.Culture = culture;
-            this.Text = text;
         }
 
         /// <summary>

src/ImageSharp/MetaData/Profiles/ICC/Various/IccLut.cs

@@ -16,8 +16,7 @@ namespace SixLabors.ImageSharp.MetaData.Profiles.Icc
         /// <param name="values">The LUT values</param>
         public IccLut(float[] values)
         {
-            Guard.NotNull(values, nameof(values));
+            this.Values = values ?? throw new ArgumentNullException(nameof(values));
-            this.Values = values;
         }
 
         /// <summary>

src/ImageSharp/PixelFormats/ColorBuilder{TPixel}.cs

@@ -28,7 +28,7 @@ namespace SixLabors.ImageSharp.PixelFormats
 
             hex = ToRgbaHex(hex);
 
-            if (hex == null || !uint.TryParse(hex, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out uint packedValue))
+            if (hex is null || !uint.TryParse(hex, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out uint packedValue))
             {
                 throw new ArgumentException("Hexadecimal string is not in the correct format.", nameof(hex));
             }

src/ImageSharp/Processing/DefaultInternalImageProcessorContext.cs

@@ -41,7 +41,7 @@ namespace SixLabors.ImageSharp.Processing
         /// <inheritdoc/>
         public Image<TPixel> Apply()
         {
-            if (!this.mutate && this.destination == null)
+            if (!this.mutate && this.destination is null)
             {
                 // Ensure we have cloned it if we are not mutating as we might have failed to register any processors
                 this.destination = this.source.Clone();
@@ -56,7 +56,7 @@ namespace SixLabors.ImageSharp.Processing
         /// <inheritdoc/>
         public IImageProcessingContext<TPixel> ApplyProcessor(IImageProcessor<TPixel> processor, Rectangle rectangle)
         {
-            if (!this.mutate && this.destination == null)
+            if (!this.mutate && this.destination is null)
             {
                 // This will only work if the first processor applied is the cloning one thus
                 // realistically for this optimization to work the resize must the first processor

src/ImageSharp/Processing/Processors/Binarization/BinaryOrderedDitherProcessor.cs

@@ -33,9 +33,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Binarization
         /// <param name="lowerColor">The color to use for pixels that are below the threshold.</param>
         public BinaryOrderedDitherProcessor(IOrderedDither dither, TPixel upperColor, TPixel lowerColor)
         {
-            Guard.NotNull(dither, nameof(dither));
+            this.Dither = dither ?? throw new ArgumentNullException(nameof(dither));
-
-            this.Dither = dither;
             this.UpperColor = upperColor;
             this.LowerColor = lowerColor;
         }

src/ImageSharp/Processing/Processors/Dithering/OrderedDitherPaletteProcessor.cs

@@ -34,8 +34,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Dithering
         public OrderedDitherPaletteProcessor(IOrderedDither dither, TPixel[] palette)
             : base(palette)
         {
-            Guard.NotNull(dither, nameof(dither));
+            this.Dither = dither ?? throw new ArgumentNullException(nameof(dither));
-            this.Dither = dither;
         }
 
         /// <summary>

src/ImageSharp/Processing/Processors/Dithering/PaletteDitherProcessorBase.cs

@@ -1,6 +1,7 @@
 // Copyright (c) Six Labors and contributors.
 // Licensed under the Apache License, Version 2.0.
 
+using System;
 using System.Collections.Generic;
 using System.Numerics;
 using System.Runtime.CompilerServices;
@@ -28,8 +29,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Dithering
         /// <param name="palette">The palette to select substitute colors from.</param>
         protected PaletteDitherProcessorBase(TPixel[] palette)
         {
-            Guard.NotNull(palette, nameof(palette));
+            this.Palette = palette ?? throw new ArgumentNullException(nameof(palette));
-            this.Palette = palette;
             this.paletteVector = new Vector4[this.Palette.Length];
             PixelOperations<TPixel>.Instance.ToScaledVector4(this.Palette, this.paletteVector, this.Palette.Length);
         }

src/ImageSharp/Processing/Processors/Quantization/OctreeFrameQuantizer{TPixel}.cs

@@ -233,7 +233,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Quantization
                 {
                     // If so, check if I have a previous node setup. This will only occur if the first color in the image
                     // happens to be black, with an alpha component of zero.
-                    if (this.previousNode == null)
+                    if (this.previousNode is null)
                     {
                         this.previousColor = pixel;
                         this.root.AddColor(ref pixel, this.maxColorBits, 0, this, ref rgba);
@@ -309,7 +309,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Quantization
             {
                 // Find the deepest level containing at least one reducible node
                 int index = this.maxColorBits - 1;
-                while ((index > 0) && (this.ReducibleNodes[index] == null))
+                while ((index > 0) && (this.ReducibleNodes[index] is null))
                 {
                     index--;
                 }
@@ -440,7 +440,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Quantization
                                     | ((rgba.R & Mask[level]) >> shift);
 
                         OctreeNode child = this.children[index];
-                        if (child == null)
+                        if (child is null)
                         {
                             // Create a new child node and store it in the array
                             child = new OctreeNode(level + 1, colorBits, octree);

src/ImageSharp/Processing/Processors/Quantization/WuFrameQuantizer{TPixel}.cs

@@ -166,7 +166,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Quantization
         /// <inheritdoc/>
         protected override TPixel[] GetPalette()
         {
-            if (this.palette == null)
+            if (this.palette is null)
             {
                 this.palette = new TPixel[this.colors];
                 for (int k = 0; k < this.colors; k++)

src/ImageSharp/Processing/Processors/Transforms/AutoOrientProcessor.cs

@@ -73,13 +73,13 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
         /// <returns>The <see cref="OrientationMode"/></returns>
         private static OrientationMode GetExifOrientation(Image<TPixel> source)
         {
-            if (source.MetaData.ExifProfile == null)
+            if (source.MetaData.ExifProfile is null)
             {
                 return OrientationMode.Unknown;
             }
 
             ExifValue value = source.MetaData.ExifProfile.GetValue(ExifTag.Orientation);
-            if (value == null)
+            if (value is null)
             {
                 return OrientationMode.Unknown;
             }

src/ImageSharp/Processing/Processors/Transforms/RotateProcessor.cs

@@ -60,7 +60,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
         protected override void AfterImageApply(Image<TPixel> source, Image<TPixel> destination, Rectangle sourceRectangle)
         {
             ExifProfile profile = destination.MetaData.ExifProfile;
-            if (profile == null)
+            if (profile is null)
             {
                 return;
             }

src/ImageSharp/Processing/Processors/Transforms/TransformHelpers.cs

@@ -23,7 +23,7 @@ namespace SixLabors.ImageSharp.Processing.Processors.Transforms
             where TPixel : struct, IPixel<TPixel>
         {
             ExifProfile profile = image.MetaData.ExifProfile;
-            if (profile == null)
+            if (profile is null)
             {
                 return;
             }

tests/ImageSharp.Tests/Processing/Processors/Transforms/SkewTest.cs

@@ -73,9 +73,9 @@ namespace SixLabors.ImageSharp.Tests.Processing.Processors.Transforms
         {
             PropertyInfo property = typeof(KnownResamplers).GetTypeInfo().GetProperty(name);
 
-            if (property == null)
+            if (property is null)
             {
-                throw new Exception("Invalid property name!");
+                throw new Exception($"No resampler named '{name}");
             }
 
             return (IResampler)property.GetValue(null);

tests/ImageSharp.Tests/Processing/Transforms/AffineTransformTests.cs

@@ -228,9 +228,9 @@ namespace SixLabors.ImageSharp.Tests.Processing.Transforms
         {
             PropertyInfo property = typeof(KnownResamplers).GetTypeInfo().GetProperty(name);
 
-            if (property == null)
+            if (property is null)
             {
-                throw new Exception("Invalid property name!");
+                throw new Exception($"No resampler named {name}");
             }
 
             return (IResampler)property.GetValue(null);

tests/ImageSharp.Tests/Processing/Transforms/ProjectiveTransformTests.cs

@@ -124,9 +124,9 @@ namespace SixLabors.ImageSharp.Tests.Processing.Transforms
         {
             PropertyInfo property = typeof(KnownResamplers).GetTypeInfo().GetProperty(name);
 
-            if (property == null)
+            if (property is null)
             {
-                throw new Exception("Invalid property name!");
+                throw new Exception($"No resampler named {name}");
             }
 
             return (IResampler)property.GetValue(null);