Migrate Gif encoder

src/ImageSharp/Formats/Gif/GifEncoder.cs

@@ -2,47 +2,30 @@
 // Licensed under the Six Labors Split License.
 
 using SixLabors.ImageSharp.Advanced;
-using SixLabors.ImageSharp.PixelFormats;
-using SixLabors.ImageSharp.Processing;
-using SixLabors.ImageSharp.Processing.Processors.Quantization;
 
 namespace SixLabors.ImageSharp.Formats.Gif;
 
 /// <summary>
 /// Image encoder for writing image data to a stream in gif format.
 /// </summary>
-public sealed class GifEncoder : IImageEncoder, IGifEncoderOptions
+public sealed class GifEncoder : QuantizingImageEncoder
 {
-    /// <summary>
-    /// Gets or sets the quantizer for reducing the color count.
-    /// Defaults to the <see cref="OctreeQuantizer"/>
-    /// </summary>
-    public IQuantizer Quantizer { get; set; } = KnownQuantizers.Octree;
-
     /// <summary>
     /// Gets or sets the color table mode: Global or local.
     /// </summary>
     public GifColorTableMode? ColorTableMode { get; set; }
 
-    /// <summary>
-    /// Gets or sets the <see cref="IPixelSamplingStrategy"/> used for quantization
-    /// when building a global color table in case of <see cref="GifColorTableMode.Global"/>.
-    /// </summary>
-    public IPixelSamplingStrategy GlobalPixelSamplingStrategy { get; set; } = new DefaultPixelSamplingStrategy();
-
     /// <inheritdoc/>
-    public void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
-        where TPixel : unmanaged, IPixel<TPixel>
     {
-        var encoder = new GifEncoderCore(image.GetConfiguration(), this);
+        GifEncoderCore encoder = new(image.GetConfiguration(), this);
         encoder.Encode(image, stream);
     }
 
     /// <inheritdoc/>
-    public Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-        where TPixel : unmanaged, IPixel<TPixel>
     {
-        var encoder = new GifEncoderCore(image.GetConfiguration(), this);
+        GifEncoderCore encoder = new(image.GetConfiguration(), this);
         return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Formats/Gif/GifEncoderCore.cs

@@ -33,6 +33,11 @@ internal sealed class GifEncoderCore : IImageEncoderInternals
     /// </summary>
     private readonly byte[] buffer = new byte[20];
 
+    /// <summary>
+    /// Whether to skip metadata during encode.
+    /// </summary>
+    private readonly bool skipMetadata;
+
     /// <summary>
     /// The quantizer used to generate the color palette.
     /// </summary>
@@ -57,14 +62,15 @@ internal sealed class GifEncoderCore : IImageEncoderInternals
     /// Initializes a new instance of the <see cref="GifEncoderCore"/> class.
     /// </summary>
     /// <param name="configuration">The configuration which allows altering default behaviour or extending the library.</param>
-    /// <param name="options">The options for the encoder.</param>
+    /// <param name="encoder">The gif encoder.</param>
-    public GifEncoderCore(Configuration configuration, IGifEncoderOptions options)
+    public GifEncoderCore(Configuration configuration, GifEncoder encoder)
     {
         this.configuration = configuration;
         this.memoryAllocator = configuration.MemoryAllocator;
-        this.quantizer = options.Quantizer;
+        this.skipMetadata = encoder.SkipMetadata;
-        this.colorTableMode = options.ColorTableMode;
+        this.quantizer = encoder.Quantizer;
-        this.pixelSamplingStrategy = options.GlobalPixelSamplingStrategy;
+        this.colorTableMode = encoder.ColorTableMode;
+        this.pixelSamplingStrategy = encoder.GlobalPixelSamplingStrategy;
     }
 
     /// <summary>
@@ -116,12 +122,15 @@ internal sealed class GifEncoderCore : IImageEncoderInternals
             this.WriteColorTable(quantized, stream);
         }
 
-        // Write the comments.
+        if (!this.skipMetadata)
-        this.WriteComments(gifMetadata, stream);
+        {
+            // Write the comments.
+            this.WriteComments(gifMetadata, stream);
 
-        // Write application extensions.
+            // Write application extensions.
-        XmpProfile xmpProfile = image.Metadata.XmpProfile ?? image.Frames.RootFrame.Metadata.XmpProfile;
+            XmpProfile xmpProfile = image.Metadata.XmpProfile ?? image.Frames.RootFrame.Metadata.XmpProfile;
-        this.WriteApplicationExtensions(stream, image.Frames.Count, gifMetadata.RepeatCount, xmpProfile);
+            this.WriteApplicationExtensions(stream, image.Frames.Count, gifMetadata.RepeatCount, xmpProfile);
+        }
 
         if (useGlobalTable)
         {

src/ImageSharp/Formats/Gif/IGifEncoderOptions.cs

@@ -1,27 +0,0 @@
-// Copyright (c) Six Labors.
-// Licensed under the Six Labors Split License.
-
-using SixLabors.ImageSharp.Processing.Processors.Quantization;
-
-namespace SixLabors.ImageSharp.Formats.Gif;
-
-/// <summary>
-/// The configuration options used for encoding gifs.
-/// </summary>
-internal interface IGifEncoderOptions
-{
-    /// <summary>
-    /// Gets the quantizer used to generate the color palette.
-    /// </summary>
-    IQuantizer Quantizer { get; }
-
-    /// <summary>
-    /// Gets the color table mode: Global or local.
-    /// </summary>
-    GifColorTableMode? ColorTableMode { get; }
-
-    /// <summary>
-    /// Gets the <see cref="IPixelSamplingStrategy"/> used for quantization when building a global color table.
-    /// </summary>
-    IPixelSamplingStrategy GlobalPixelSamplingStrategy { get; }
-}