Add some more comments

src/ImageSharp/Formats/Exr/ExrHeaderAttributes.cs

@@ -5,6 +5,10 @@ using SixLabors.ImageSharp.Formats.Exr.Constants;
 
 namespace SixLabors.ImageSharp.Formats.Exr;
 
+/// <summary>
+/// The header of an EXR image.
+/// <see href="https://openexr.com/en/latest/TechnicalIntroduction.html#header"/>
+/// </summary>
 internal class ExrHeaderAttributes
 {
     public ExrHeaderAttributes(
@@ -33,25 +37,58 @@ internal class ExrHeaderAttributes
         this.ChunkCount = chunkCount;
     }
 
+    /// <summary>
+    /// Gets or sets a description of the image channels stored in the file.
+    /// </summary>
     public IList<ExrChannelInfo> Channels { get; set; }
 
+    /// <summary>
+    /// Gets or sets the compression method applied to the pixel data of all channels in the file.
+    /// </summary>
     public ExrCompression Compression { get; set; }
 
+    /// <summary>
+    /// Gets or sets the image’s data window.
+    /// </summary>
     public ExrBox2i DataWindow { get; set; }
 
+    /// <summary>
+    /// Gets or sets the image’s display window.
+    /// </summary>
     public ExrBox2i DisplayWindow { get; set; }
 
+    /// <summary>
+    /// Gets or sets in what order the scan lines in the file are stored in the file (increasing Y, decreasing Y, or, for tiled images, also random Y).
+    /// </summary>
     public ExrLineOrder LineOrder { get; set; }
 
+    /// <summary>
+    /// Gets or sets the aspect ratio of the image.
+    /// </summary>
     public float AspectRatio { get; set; }
 
+    /// <summary>
+    /// Gets or sets the screen width.
+    /// </summary>
     public float ScreenWindowWidth { get; set; }
 
+    /// <summary>
+    /// Gets or sets the screen window center.
+    /// </summary>
     public PointF ScreenWindowCenter { get; set; }
 
+    /// <summary>
+    /// Gets or sets the number of horizontal tiles.
+    /// </summary>
     public uint? TileXSize { get; set; }
 
+    /// <summary>
+    /// Gets or sets the number of vertical tiles.
+    /// </summary>
     public uint? TileYSize { get; set; }
 
+    /// <summary>
+    /// Gets or sets the chunk count. Indicates the number of chunks in this part. Required if the multipart bit (12) is set.
+    /// </summary>
     public int? ChunkCount { get; set; }
 }

src/ImageSharp/Formats/Exr/ExrUtils.cs

@@ -7,6 +7,12 @@ namespace SixLabors.ImageSharp.Formats.Exr;
 
 internal static class ExrUtils
 {
+    /// <summary>
+    /// Calcualtes the required bytes for a pixel row.
+    /// </summary>
+    /// <param name="channels">The image channels array.</param>
+    /// <param name="width">The width in pixels of a row.</param>
+    /// <returns>The number of bytes per row.</returns>
     public static uint CalculateBytesPerRow(IList<ExrChannelInfo> channels, uint width)
     {
         uint bytesPerRow = 0;
@@ -32,6 +38,11 @@ internal static class ExrUtils
         return bytesPerRow;
     }
 
+    /// <summary>
+    /// Determines how many pixel rows there are in a block. This varies depending on the compression used.
+    /// </summary>
+    /// <param name="compression">The compression used.</param>
+    /// <returns>Pixel rows in a block.</returns>
     public static uint RowsPerBlock(ExrCompression compression) => compression switch
     {
         ExrCompression.Zip or ExrCompression.Pxr24 => 16,

src/ImageSharp/Formats/Exr/IExrEncoderOptions.cs

@@ -1,17 +0,0 @@
-// Copyright (c) Six Labors.
-// Licensed under the Six Labors Split License.
-
-using SixLabors.ImageSharp.Formats.Exr.Constants;
-
-namespace SixLabors.ImageSharp.Formats.Exr;
-
-/// <summary>
-/// Configuration options for use during OpenExr encoding.
-/// </summary>
-internal interface IExrEncoderOptions
-{
-    /// <summary>
-    /// Gets the pixel type of the image.
-    /// </summary>
-    ExrPixelType? PixelType { get; }
-}