Can now save some ICC profiles

CMYK Image throws an error when trying to parse/write entries

src/ImageSharp/Formats/Jpeg/JpegDecoderCore.cs

@@ -6,6 +6,7 @@
 namespace ImageSharp.Formats
 {
     using System;
+    using System.Collections.Generic;
     using System.IO;
     using System.Runtime.CompilerServices;
     using System.Threading.Tasks;
@@ -88,11 +89,6 @@ namespace ImageSharp.Formats
         /// </summary>
         private bool isExif;
 
-        /// <summary>
-        /// Whether the image has an ICC header
-        /// </summary>
-        private bool isIcc;
-
         /// <summary>
         /// The vertical resolution. Calculated if the image has a JFIF header.
         /// </summary>
@@ -997,11 +993,11 @@ namespace ImageSharp.Formats
                 identifier[10] == 'E' &&
                 identifier[11] == '\0')
             {
-                this.isIcc = true;
                 remaining -= Icclength;
                 byte[] profile = new byte[remaining];
                 this.InputProcessor.ReadFull(profile, 0, remaining);
-                metadata.IccProfile = new IccProfile(profile);
+
+                metadata.IccProfiles.Add(new IccProfile(profile));
             }
         }
 
@@ -1021,8 +1017,11 @@ namespace ImageSharp.Formats
             remaining -= 13;
 
             // TODO: We should be using constants for this.
-            this.isJfif = this.Temp[0] == 'J' && this.Temp[1] == 'F' && this.Temp[2] == 'I' && this.Temp[3] == 'F'
+            this.isJfif = this.Temp[0] == 'J' &&
-                          && this.Temp[4] == '\x00';
+                          this.Temp[1] == 'F' &&
+                          this.Temp[2] == 'I' &&
+                          this.Temp[3] == 'F' &&
+                          this.Temp[4] == '\x00';
 
             if (this.isJfif)
             {

src/ImageSharp/Formats/Jpeg/JpegEncoderCore.cs

@@ -6,7 +6,9 @@
 namespace ImageSharp.Formats
 {
     using System.Buffers;
+    using System.Collections.Generic;
     using System.IO;
+    using System.Linq;
     using System.Runtime.CompilerServices;
     using ImageSharp.Formats.Jpg;
     using ImageSharp.Formats.Jpg.Components;
@@ -109,7 +111,7 @@ namespace ImageSharp.Formats
         /// <summary>
         /// A scratch buffer to reduce allocations.
         /// </summary>
-        private readonly byte[] buffer = new byte[16];
+        private readonly byte[] buffer = new byte[20];
 
         /// <summary>
         /// A buffer for reducing the number of stream writes when emitting Huffman tables. 64 seems to be enough.
@@ -514,19 +516,17 @@ namespace ImageSharp.Formats
             this.buffer[12] = 0x01; // versionlo
             this.buffer[13] = 0x01; // xyunits as dpi
 
-            // No thumbnail
-            this.buffer[14] = 0x00; // Thumbnail width
-            this.buffer[15] = 0x00; // Thumbnail height
-
-            this.outputStream.Write(this.buffer, 0, 16);
-
             // Resolution. Big Endian
-            this.buffer[0] = (byte)(horizontalResolution >> 8);
+            this.buffer[14] = (byte)(horizontalResolution >> 8);
-            this.buffer[1] = (byte)horizontalResolution;
+            this.buffer[15] = (byte)horizontalResolution;
-            this.buffer[2] = (byte)(verticalResolution >> 8);
+            this.buffer[16] = (byte)(verticalResolution >> 8);
-            this.buffer[3] = (byte)verticalResolution;
+            this.buffer[17] = (byte)verticalResolution;
 
-            this.outputStream.Write(this.buffer, 0, 4);
+            // No thumbnail
+            this.buffer[18] = 0x00; // Thumbnail width
+            this.buffer[19] = 0x00; // Thumbnail height
+
+            this.outputStream.Write(this.buffer, 0, 20);
         }
 
         /// <summary>
@@ -674,7 +674,7 @@ namespace ImageSharp.Formats
         /// <exception cref="ImageFormatException">
         /// Thrown if the EXIF profile size exceeds the limit
         /// </exception>
-        private void WriteProfile(ExifProfile exifProfile)
+        private void WriteExifProfile(ExifProfile exifProfile)
         {
             const int Max = 65533;
             byte[] data = exifProfile?.ToByteArray();
@@ -699,6 +699,66 @@ namespace ImageSharp.Formats
             this.outputStream.Write(data, 0, data.Length);
         }
 
+        /// <summary>
+        /// Writes the ICC profiles.
+        /// </summary>
+        /// <param name="iccProfiles">The list of ICC profiles.</param>
+        /// <exception cref="ImageFormatException">
+        /// Thrown if any of the ICC profiles size exceeds the limit
+        /// </exception>
+        private void WriteICCProfiles(IList<IccProfile> iccProfiles)
+        {
+            // Just incase someone set the value to null by accident.
+            if (iccProfiles == null || !iccProfiles.Any())
+            {
+                return;
+            }
+
+            const int Max = 65533;
+            int count = iccProfiles.Count;
+
+            for (int i = 1; i <= count; i++)
+            {
+                byte[] data = iccProfiles[i - 1]?.ToByteArray();
+
+                if (data == null || data.Length == 0)
+                {
+                    continue;
+                }
+
+                if (data.Length > Max)
+                {
+                    throw new ImageFormatException($"ICC profile size exceeds limit. nameof{Max}");
+                }
+
+                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);
+
+                this.outputStream.Write(this.buffer, 0, 4);
+
+                this.buffer[0] = (byte)'I';
+                this.buffer[1] = (byte)'C';
+                this.buffer[2] = (byte)'C';
+                this.buffer[3] = (byte)'_';
+                this.buffer[4] = (byte)'P';
+                this.buffer[5] = (byte)'R';
+                this.buffer[6] = (byte)'O';
+                this.buffer[7] = (byte)'F';
+                this.buffer[8] = (byte)'I';
+                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[13] = (byte)count; // The total number of profiles.
+
+                this.outputStream.Write(this.buffer, 0, 14);
+                this.outputStream.Write(data, 0, data.Length);
+            }
+        }
+
         /// <summary>
         /// Writes the metadata profiles to the image.
         /// </summary>
@@ -713,7 +773,8 @@ namespace ImageSharp.Formats
             }
 
             image.MetaData.SyncProfiles();
-            this.WriteProfile(image.MetaData.ExifProfile);
+            this.WriteExifProfile(image.MetaData.ExifProfile);
+            this.WriteICCProfiles(image.MetaData.IccProfiles);
         }
 
         /// <summary>

src/ImageSharp/MetaData/ImageMetaData.cs

@@ -7,6 +7,7 @@ namespace ImageSharp
 {
     using System;
     using System.Collections.Generic;
+    using System.Linq;
 
     /// <summary>
     /// Encapsulates the metadata of an image.
@@ -67,6 +68,15 @@ namespace ImageSharp
             {
                 this.ExifProfile = null;
             }
+
+            if (other.IccProfiles != null && other.IccProfiles.Any())
+            {
+                this.IccProfiles = new List<IccProfile>(other.IccProfiles);
+            }
+            else
+            {
+                this.ExifProfile = null;
+            }
         }
 
         /// <summary>
@@ -83,10 +93,10 @@ namespace ImageSharp
 
             set
             {
-              if (value > 0)
+                if (value > 0)
-              {
+                {
-                  this.horizontalResolution = value;
+                    this.horizontalResolution = value;
-              }
+                }
             }
         }
 
@@ -117,9 +127,9 @@ namespace ImageSharp
         public ExifProfile ExifProfile { get; set; }
 
         /// <summary>
-        /// Gets or sets the ICC profile.
+        /// Gets or sets the list of ICC profiles.
         /// </summary>
-        public IccProfile IccProfile { get; set; }
+        public IList<IccProfile> IccProfiles { get; set; } = new List<IccProfile>();
 
         /// <summary>
         /// Gets or sets the frame delay for animated images.

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

@@ -12,7 +12,7 @@ namespace ImageSharp
     /// <summary>
     /// Provides methods to write ICC data types
     /// </summary>
-    internal sealed partial class IccDataWriter
+    internal sealed partial class IccDataWriter : IDisposable
     {
         private static readonly bool IsLittleEndian = BitConverter.IsLittleEndian;
         private static readonly Encoding AsciiEncoding = Encoding.GetEncoding("ASCII");
@@ -22,6 +22,11 @@ namespace ImageSharp
         /// </summary>
         private readonly MemoryStream dataStream;
 
+        /// <summary>
+        /// To detect redundant calls
+        /// </summary>
+        private bool isDisposed = false;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="IccDataWriter"/> class.
         /// </summary>
@@ -167,6 +172,12 @@ namespace ImageSharp
             return this.WriteEmpty(p >= 4 ? 0 : p);
         }
 
+        /// <inheritdoc/>
+        public void Dispose()
+        {
+            this.Dispose(true);
+        }
+
         /// <summary>
         /// Writes given bytes from pointer
         /// </summary>
@@ -228,5 +239,18 @@ namespace ImageSharp
 
             return count;
         }
+
+        private void Dispose(bool disposing)
+        {
+            if (!this.isDisposed)
+            {
+                if (disposing)
+                {
+                    this.dataStream?.Dispose();
+                }
+
+                this.isDisposed = true;
+            }
+        }
     }
 }

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

@@ -124,6 +124,16 @@ namespace ImageSharp
 
 #endif
 
+        /// <summary>
+        /// Converts this instance to a byte array.
+        /// </summary>
+        /// <returns>The <see cref="T:byte[]"/></returns>
+        public byte[] ToByteArray()
+        {
+            IccWriter writer = new IccWriter();
+            return writer.Write(this);
+        }
+
         private void InitializeHeader()
         {
             if (this.header != null)

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

@@ -22,11 +22,13 @@ namespace ImageSharp
         {
             Guard.NotNull(profile, nameof(profile));
 
-            IccDataWriter writer = new IccDataWriter();
+            using (IccDataWriter writer = new IccDataWriter())
-            IccTagTableEntry[] tagTable = this.WriteTagData(writer, profile.Entries);
+            {
-            this.WriteTagTable(writer, tagTable);
+                IccTagTableEntry[] tagTable = this.WriteTagData(writer, profile.Entries);
-            this.WriteHeader(writer, profile.Header);
+                this.WriteTagTable(writer, tagTable);
-            return writer.GetData();
+                this.WriteHeader(writer, profile.Header);
+                return writer.GetData();
+            }
         }
 
         private void WriteHeader(IccDataWriter writer, IccProfileHeader header)