Can now read/write all ICC Profiles

src/ImageSharp/Formats/Jpeg/JpegDecoderCore.cs

@@ -1000,7 +1000,14 @@ namespace ImageSharp.Formats
                 byte[] profile = new byte[remaining];
                 this.InputProcessor.ReadFull(profile, 0, remaining);
 
-                metadata.IccProfiles.Add(new IccProfile(profile));
+                if (metadata.IccProfile == null)
+                {
+                    metadata.IccProfile = new IccProfile(profile);
+                }
+                else
+                {
+                    metadata.IccProfile.Extend(profile);
+                }
             }
         }
 

src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs

@@ -700,42 +700,60 @@ namespace ImageSharp.Formats
         }
 
         /// <summary>
-        /// Writes the ICC profiles.
+        /// Writes the ICC profile.
         /// </summary>
-        /// <param name="iccProfiles">The list of ICC profiles.</param>
+        /// <param name="iccProfile">The ICC profile to write.</param>
         /// <exception cref="ImageFormatException">
         /// Thrown if any of the ICC profiles size exceeds the limit
         /// </exception>
-        private void WriteICCProfiles(IList<IccProfile> iccProfiles)
+        private void WriteIccProfile(IccProfile iccProfile)
         {
             // Just incase someone set the value to null by accident.
-            if (iccProfiles == null || !iccProfiles.Any())
+            if (iccProfile == null)
             {
                 return;
             }
 
+            const int IccOverheadLength = 14;
             const int Max = 65533;
-            int count = iccProfiles.Count;
+            const int MaxData = Max - IccOverheadLength;
 
-            for (int i = 1; i <= count; i++)
+            byte[] data = iccProfile.ToByteArray();
+
+            if (data == null || data.Length == 0)
             {
-                byte[] data = iccProfiles[i - 1]?.ToByteArray();
+                return;
+            }
 
-                if (data == null || data.Length == 0)
-                {
-                    continue;
-                }
+            // Calculate the number of markers we'll need, rounding up of course
+            int dataLength = data.Length;
+            int count = dataLength / MaxData;
 
-                if (data.Length > Max)
+            if (count * MaxData != dataLength)
+            {
+                count++;
+            }
+
+            // Per spec, counting starts at 1.
+            int current = 1;
+            int offset = 0;
+
+            while (dataLength > 0)
+            {
+                int length = dataLength; // Number of bytes to write.
+
+                if (length > MaxData)
                 {
-                    throw new ImageFormatException($"ICC profile size exceeds limit. nameof{Max}");
+                    length = MaxData;
                 }
 
+                dataLength -= length;
+
                 this.buffer[0] = JpegConstants.Markers.XFF;
                 this.buffer[1] = JpegConstants.Markers.APP2; // Application Marker
-                int length = data.Length + 16;
-                this.buffer[2] = (byte)((length >> 8) & 0xFF);
-                this.buffer[3] = (byte)(length & 0xFF);
+                int markerLength = length + 16;
+                this.buffer[2] = (byte)((markerLength >> 8) & 0xFF);
+                this.buffer[3] = (byte)(markerLength & 0xFF);
 
                 this.outputStream.Write(this.buffer, 0, 4);
 
@@ -751,11 +769,14 @@ namespace ImageSharp.Formats
                 this.buffer[9] = (byte)'L';
                 this.buffer[10] = (byte)'E';
                 this.buffer[11] = 0x00;
-                this.buffer[12] = (byte)i; // The position within the collection.
+                this.buffer[12] = (byte)current; // The position within the collection.
                 this.buffer[13] = (byte)count; // The total number of profiles.
 
-                this.outputStream.Write(this.buffer, 0, 14);
-                this.outputStream.Write(data, 0, data.Length);
+                this.outputStream.Write(this.buffer, 0, IccOverheadLength);
+                this.outputStream.Write(data, offset, length);
+
+                current++;
+                offset += length;
             }
         }
 
@@ -774,7 +795,7 @@ namespace ImageSharp.Formats
 
             image.MetaData.SyncProfiles();
             this.WriteExifProfile(image.MetaData.ExifProfile);
-            this.WriteICCProfiles(image.MetaData.IccProfiles);
+            this.WriteIccProfile(image.MetaData.IccProfile);
         }
 
         /// <summary>

src/ImageSharp/MetaData/ImageMetaData.cs

@@ -6,7 +6,6 @@
 namespace ImageSharp
 {
     using System.Collections.Generic;
-    using System.Linq;
     using ImageSharp.Formats;
 
     /// <summary>
@@ -61,36 +60,23 @@ namespace ImageSharp
                 this.Properties.Add(new ImageProperty(property));
             }
 
-            if (other.ExifProfile != null)
-            {
-                this.ExifProfile = new ExifProfile(other.ExifProfile);
-            }
-            else
-            {
-                this.ExifProfile = null;
-            }
+            this.ExifProfile = other.ExifProfile != null
+                ? new ExifProfile(other.ExifProfile)
+                : null;
 
-            if (other.IccProfiles != null && other.IccProfiles.Any())
-            {
-                this.IccProfiles = new List<IccProfile>(other.IccProfiles);
-            }
-            else
-            {
-                this.IccProfiles = new List<IccProfile>();
-            }
+            this.IccProfile = other.IccProfile != null
+                ? new IccProfile(other.IccProfile)
+                : null;
         }
 
         /// <summary>
-        /// Gets or sets the resolution of the image in x- direction. It is defined as
-        ///  number of dots per inch and should be an positive value.
+        /// Gets or sets the resolution of the image in x- direction.
+        /// It is defined as the number of dots per inch and should be an positive value.
         /// </summary>
         /// <value>The density of the image in x- direction.</value>
         public double HorizontalResolution
         {
-            get
-            {
-                return this.horizontalResolution;
-            }
+            get => this.horizontalResolution;
 
             set
             {
@@ -102,16 +88,13 @@ namespace ImageSharp
         }
 
         /// <summary>
-        /// Gets or sets the resolution of the image in y- direction. It is defined as
-        /// number of dots per inch and should be an positive value.
+        /// Gets or sets the resolution of the image in y- direction.
+        /// It is defined as the number of dots per inch and should be an positive value.
         /// </summary>
         /// <value>The density of the image in y- direction.</value>
         public double VerticalResolution
         {
-            get
-            {
-                return this.verticalResolution;
-            }
+            get => this.verticalResolution;
 
             set
             {
@@ -130,7 +113,7 @@ namespace ImageSharp
         /// <summary>
         /// Gets or sets the list of ICC profiles.
         /// </summary>
-        public IList<IccProfile> IccProfiles { get; set; } = new List<IccProfile>();
+        public IccProfile IccProfile { get; set; }
 
         /// <inheritdoc/>
         public int FrameDelay { get; set; }

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

@@ -7,6 +7,8 @@ namespace ImageSharp
 {
     using System.Numerics;
 
+    using ImageSharp.Memory;
+
     /// <summary>
     /// Provides methods to write ICC data types
     /// </summary>

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

@@ -5,9 +5,9 @@
 
 namespace ImageSharp
 {
+    using System;
     using System.Collections.Generic;
 #if !NETSTANDARD1_1
-    using System;
     using System.Security.Cryptography;
 #endif
 
@@ -19,7 +19,7 @@ namespace ImageSharp
         /// <summary>
         /// The byte array to read the ICC profile from
         /// </summary>
-        private readonly byte[] data;
+        private byte[] data;
 
         /// <summary>
         /// The backing file for the <see cref="Entries"/> property
@@ -35,7 +35,7 @@ namespace ImageSharp
         /// Initializes a new instance of the <see cref="IccProfile"/> class.
         /// </summary>
         public IccProfile()
-            : this(null)
+            : this((byte[])null)
         {
         }
 
@@ -48,6 +48,20 @@ namespace ImageSharp
             this.data = data;
         }
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="IccProfile"/> class
+        /// by making a copy from another ICC profile.
+        /// </summary>
+        /// <param name="other">The other ICC profile, where the clone should be made from.</param>
+        /// <exception cref="System.ArgumentNullException"><paramref name="other"/> is null.</exception>>
+        public IccProfile(IccProfile other)
+        {
+            Guard.NotNull(other, nameof(other));
+
+            // TODO: Do we need to copy anything else?
+            this.data = other.data;
+        }
+
         /// <summary>
         /// Initializes a new instance of the <see cref="IccProfile"/> class.
         /// </summary>
@@ -73,10 +87,7 @@ namespace ImageSharp
                 return this.header;
             }
 
-            set
-            {
-                this.header = value;
-            }
+            set => this.header = value;
         }
 
         /// <summary>
@@ -106,7 +117,7 @@ namespace ImageSharp
             byte[] header = new byte[128];
             Buffer.BlockCopy(data, 0, header, 0, 128);
 
-            using (MD5 md5 = MD5.Create())
+            using (var md5 = MD5.Create())
             {
                 // Zero out some values
                 Array.Clear(header, 44, 4);     // Profile flags
@@ -117,20 +128,31 @@ namespace ImageSharp
                 byte[] hash = md5.ComputeHash(data);
 
                 // Read values from hash
-                IccDataReader reader = new IccDataReader(hash);
+                var reader = new IccDataReader(hash);
                 return reader.ReadProfileId();
             }
         }
 
 #endif
 
+        /// <summary>
+        /// Extends the profile with additional data.
+        /// </summary>
+        /// <param name="bytes">The array containing addition profile data.</param>
+        public void Extend(byte[] bytes)
+        {
+            int currentLength = this.data.Length;
+            Array.Resize(ref this.data, currentLength + bytes.Length);
+            Buffer.BlockCopy(bytes, 0, this.data, currentLength, bytes.Length);
+        }
+
         /// <summary>
         /// Converts this instance to a byte array.
         /// </summary>
         /// <returns>The <see cref="T:byte[]"/></returns>
         public byte[] ToByteArray()
         {
-            IccWriter writer = new IccWriter();
+            var writer = new IccWriter();
             return writer.Write(this);
         }
 
@@ -147,7 +169,7 @@ namespace ImageSharp
                 return;
             }
 
-            IccReader reader = new IccReader();
+            var reader = new IccReader();
             this.header = reader.ReadHeader(this.data);
         }
 
@@ -164,7 +186,7 @@ namespace ImageSharp
                 return;
             }
 
-            IccReader reader = new IccReader();
+            var reader = new IccReader();
             this.entries = new List<IccTagDataEntry>(reader.ReadTagData(this.data));
         }
     }

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

@@ -8,6 +8,8 @@ namespace ImageSharp
     using System;
     using System.Linq;
 
+    using ImageSharp.Memory;
+
     /// <summary>
     /// A matrix element to process data
     /// </summary>

tests/ImageSharp.Tests/MetaData/Profiles/ICC/DataWriter/IccDataWriter.MatrixTests.cs

@@ -6,6 +6,9 @@
 namespace ImageSharp.Tests.Icc
 {
     using System.Numerics;
+
+    using ImageSharp.Memory;
+
     using Xunit;
 
     public class IccDataWriterMatrixTests

tests/ImageSharp.Tests/TestDataIcc/IccTestDataMatrix.cs

@@ -7,6 +7,8 @@ using System.Numerics;
 
 namespace ImageSharp.Tests
 {
+    using ImageSharp.Memory;
+
     internal static class IccTestDataMatrix
     {
         #region 2D