Re-introduce IImageEncoder and split encoding pipelines.

src/ImageSharp/Advanced/AdvancedImageExtensions.cs

@@ -21,8 +21,8 @@ public static class AdvancedImageExtensions
     /// <param name="filePath">The target file path to save the image to.</param>
     /// <exception cref="ArgumentNullException">The file path is null.</exception>
     /// <exception cref="NotSupportedException">No encoder available for provided path.</exception>
-    /// <returns>The matching <see cref="ImageEncoder"/>.</returns>
+    /// <returns>The matching <see cref="IImageEncoder"/>.</returns>
-    public static ImageEncoder DetectEncoder(this Image source, string filePath)
+    public static IImageEncoder DetectEncoder(this Image source, string filePath)
     {
         Guard.NotNull(filePath, nameof(filePath));
 
@@ -40,13 +40,13 @@ public static class AdvancedImageExtensions
             throw new NotSupportedException(sb.ToString());
         }
 
-        ImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
+        IImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
 
         if (encoder is null)
         {
             StringBuilder sb = new();
             sb.AppendLine(CultureInfo.InvariantCulture, $"No encoder was found for extension '{ext}' using image format '{format.Name}'. Registered encoders include:");
-            foreach (KeyValuePair<IImageFormat, ImageEncoder> enc in source.GetConfiguration().ImageFormatsManager.ImageEncoders)
+            foreach (KeyValuePair<IImageFormat, IImageEncoder> enc in source.GetConfiguration().ImageFormatsManager.ImageEncoders)
             {
                 sb.AppendFormat(CultureInfo.InvariantCulture, " - {0} : {1}{2}", enc.Key, enc.Value.GetType().Name, Environment.NewLine);
             }

src/ImageSharp/Advanced/AotCompilerTools.cs

@@ -230,7 +230,7 @@ internal static class AotCompilerTools
     }
 
     /// <summary>
-    /// This method pre-seeds the all <see cref="ImageEncoder"/> in the AoT compiler.
+    /// This method pre-seeds the all <see cref="IImageEncoder"/> in the AoT compiler.
     /// </summary>
     /// <typeparam name="TPixel">The pixel format.</typeparam>
     [Preserve]
@@ -266,14 +266,14 @@ internal static class AotCompilerTools
     }
 
     /// <summary>
-    /// This method pre-seeds the <see cref="ImageEncoder"/> in the AoT compiler.
+    /// This method pre-seeds the <see cref="IImageEncoder"/> in the AoT compiler.
     /// </summary>
     /// <typeparam name="TPixel">The pixel format.</typeparam>
     /// <typeparam name="TEncoder">The encoder.</typeparam>
     [Preserve]
     private static void AotCompileImageEncoder<TPixel, TEncoder>()
         where TPixel : unmanaged, IPixel<TPixel>
-        where TEncoder : ImageEncoder
+        where TEncoder : IImageEncoder
     {
         default(TEncoder).Encode<TPixel>(default, default);
         default(TEncoder).EncodeAsync<TPixel>(default, default, default);

src/ImageSharp/Formats/Bmp/BmpEncoder.cs

@@ -24,16 +24,9 @@ public sealed class BmpEncoder : QuantizingImageEncoder
     public bool SupportTransparency { get; init; }
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         BmpEncoderCore encoder = new(this, image.GetMemoryAllocator());
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        BmpEncoderCore encoder = new(this, image.GetMemoryAllocator());
-        return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Formats/Gif/GifEncoder.cs

@@ -16,16 +16,9 @@ public sealed class GifEncoder : QuantizingImageEncoder
     public GifColorTableMode? ColorTableMode { get; init; }
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         GifEncoderCore encoder = new(image.GetConfiguration(), this);
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        GifEncoderCore encoder = new(image.GetConfiguration(), this);
-        return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Formats/ImageEncoder.cs → src/ImageSharp/Formats/IImageEncoder.cs

@@ -2,15 +2,13 @@
 // Licensed under the Six Labors Split License.
 
 using SixLabors.ImageSharp.PixelFormats;
-using SixLabors.ImageSharp.Processing;
-using SixLabors.ImageSharp.Processing.Processors.Quantization;
 
 namespace SixLabors.ImageSharp.Formats;
 
 /// <summary>
-/// The base class for all image encoders.
+/// Defines the contract for all image encoders.
 /// </summary>
-public abstract class ImageEncoder
+public interface IImageEncoder
 {
     /// <summary>
     /// Gets a value indicating whether to ignore decoded metadata when encoding.
@@ -23,7 +21,7 @@ public abstract class ImageEncoder
     /// <typeparam name="TPixel">The pixel format.</typeparam>
     /// <param name="image">The <see cref="Image{TPixel}" /> to encode from.</param>
     /// <param name="stream">The <see cref="Stream" /> to encode the image data to.</param>
-    public abstract void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    public void Encode<TPixel>(Image<TPixel> image, Stream stream)
         where TPixel : unmanaged, IPixel<TPixel>;
 
     /// <summary>
@@ -34,22 +32,6 @@ public abstract class ImageEncoder
     /// <param name="stream">The <see cref="Stream" /> to encode the image data to.</param>
     /// <param name="cancellationToken">The token to monitor for cancellation requests.</param>
     /// <returns>A <see cref="Task" /> representing the asynchronous operation.</returns>
-    public abstract Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+    public Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
         where TPixel : unmanaged, IPixel<TPixel>;
 }
-
-/// <summary>
-/// The base class for all image encoders that allow color palette generation via quantization.
-/// </summary>
-public abstract class QuantizingImageEncoder : ImageEncoder
-{
-    /// <summary>
-    /// Gets the quantizer used to generate the color palette.
-    /// </summary>
-    public IQuantizer Quantizer { get; init; } = KnownQuantizers.Octree;
-
-    /// <summary>
-    /// Gets the <see cref="IPixelSamplingStrategy"/> used for quantization when building color palettes.
-    /// </summary>
-    public IPixelSamplingStrategy PixelSamplingStrategy { get; init; } = new DefaultPixelSamplingStrategy();
-}

src/ImageSharp/Formats/IImageEncoderInternals.cs

@@ -1,4 +1,4 @@
-// Copyright (c) Six Labors.
+// Copyright (c) Six Labors.
 // Licensed under the Six Labors Split License.
 
 using SixLabors.ImageSharp.PixelFormats;
@@ -6,7 +6,7 @@ using SixLabors.ImageSharp.PixelFormats;
 namespace SixLabors.ImageSharp.Formats;
 
 /// <summary>
-/// Abstraction for shared internals for ***DecoderCore implementations to be used with <see cref="ImageEncoderUtilities"/>.
+/// Abstraction for shared internals for ***DecoderCore implementations.
 /// </summary>
 internal interface IImageEncoderInternals
 {

src/ImageSharp/Formats/ImageDecoder.cs

@@ -13,6 +13,53 @@ namespace SixLabors.ImageSharp.Formats;
 /// </summary>
 public abstract class ImageDecoder : IImageDecoder
 {
+    /// <inheritdoc/>
+    public Image<TPixel> Decode<TPixel>(DecoderOptions options, Stream stream)
+        where TPixel : unmanaged, IPixel<TPixel>
+        => WithSeekableStream(
+              options,
+              stream,
+              s => this.Decode<TPixel>(options, s, default));
+
+    /// <inheritdoc/>
+    public Image Decode(DecoderOptions options, Stream stream)
+        => WithSeekableStream(
+              options,
+              stream,
+              s => this.Decode(options, s, default));
+
+    /// <inheritdoc/>
+    public Task<Image<TPixel>> DecodeAsync<TPixel>(DecoderOptions options, Stream stream, CancellationToken cancellationToken)
+        where TPixel : unmanaged, IPixel<TPixel>
+        => WithSeekableStreamAsync(
+            options,
+            stream,
+            (s, ct) => this.Decode<TPixel>(options, s, ct),
+            cancellationToken);
+
+    /// <inheritdoc/>
+    public Task<Image> DecodeAsync(DecoderOptions options, Stream stream, CancellationToken cancellationToken)
+        => WithSeekableStreamAsync(
+            options,
+            stream,
+            (s, ct) => this.Decode(options, s, ct),
+            cancellationToken);
+
+    /// <inheritdoc/>
+    public IImageInfo Identify(DecoderOptions options, Stream stream)
+          => WithSeekableStream(
+              options,
+              stream,
+              s => this.Identify(options, s, default));
+
+    /// <inheritdoc/>
+    public Task<IImageInfo> IdentifyAsync(DecoderOptions options, Stream stream, CancellationToken cancellationToken)
+         => WithSeekableStreamAsync(
+             options,
+             stream,
+             (s, ct) => this.Identify(options, s, ct),
+             cancellationToken);
+
     /// <summary>
     /// Decodes the image from the specified stream to an <see cref="Image{TPixel}" /> of a specific pixel type.
     /// </summary>
@@ -93,53 +140,6 @@ public abstract class ImageDecoder : IImageDecoder
         return currentSize.Width != targetSize.Width && currentSize.Height != targetSize.Height;
     }
 
-    /// <inheritdoc/>
-    public Image<TPixel> Decode<TPixel>(DecoderOptions options, Stream stream)
-        where TPixel : unmanaged, IPixel<TPixel>
-        => WithSeekableStream(
-              options,
-              stream,
-              s => this.Decode<TPixel>(options, s, default));
-
-    /// <inheritdoc/>
-    public Image Decode(DecoderOptions options, Stream stream)
-        => WithSeekableStream(
-              options,
-              stream,
-              s => this.Decode(options, s, default));
-
-    /// <inheritdoc/>
-    public Task<Image<TPixel>> DecodeAsync<TPixel>(DecoderOptions options, Stream stream, CancellationToken cancellationToken)
-        where TPixel : unmanaged, IPixel<TPixel>
-        => WithSeekableStreamAsync(
-            options,
-            stream,
-            (s, ct) => this.Decode<TPixel>(options, s, ct),
-            cancellationToken);
-
-    /// <inheritdoc/>
-    public Task<Image> DecodeAsync(DecoderOptions options, Stream stream, CancellationToken cancellationToken)
-        => WithSeekableStreamAsync(
-            options,
-            stream,
-            (s, ct) => this.Decode(options, s, ct),
-            cancellationToken);
-
-    /// <inheritdoc/>
-    public IImageInfo Identify(DecoderOptions options, Stream stream)
-          => WithSeekableStream(
-              options,
-              stream,
-              s => this.Identify(options, s, default));
-
-    /// <inheritdoc/>
-    public Task<IImageInfo> IdentifyAsync(DecoderOptions options, Stream stream, CancellationToken cancellationToken)
-         => WithSeekableStreamAsync(
-             options,
-             stream,
-             (s, ct) => this.Identify(options, s, ct),
-             cancellationToken);
-
     internal static T WithSeekableStream<T>(
         DecoderOptions options,
         Stream stream,
@@ -213,7 +213,7 @@ public abstract class ImageDecoder : IImageDecoder
         // code below to copy the stream to an in-memory buffer before invoking the action.
 
         // TODO: Avoid the existing double copy caused by calling IdentifyAsync followed by DecodeAsync.
-        // Perhaps we can make overloads accepting the chunked memorystream?
+        // Perhaps we can make overloads accepting the chunked memorystream? Or maybe AOT is good with pattern matching against types?
         Configuration configuration = options.Configuration;
         using ChunkedMemoryStream memoryStream = new(configuration.MemoryAllocator);
         await stream.CopyToAsync(memoryStream, configuration.StreamProcessingBufferSize, cancellationToken).ConfigureAwait(false);

src/ImageSharp/Formats/ImageEncoderUtilities.cs

@@ -1,56 +0,0 @@
-// Copyright (c) Six Labors.
-// Licensed under the Six Labors Split License.
-
-using SixLabors.ImageSharp.Advanced;
-using SixLabors.ImageSharp.PixelFormats;
-
-namespace SixLabors.ImageSharp.Formats;
-
-internal static class ImageEncoderUtilities
-{
-    public static async Task EncodeAsync<TPixel>(
-        this IImageEncoderInternals encoder,
-        Image<TPixel> image,
-        Stream stream,
-        CancellationToken cancellationToken)
-        where TPixel : unmanaged, IPixel<TPixel>
-    {
-        Configuration configuration = image.GetConfiguration();
-        if (stream.CanSeek)
-        {
-            await DoEncodeAsync(stream).ConfigureAwait(false);
-        }
-        else
-        {
-            using MemoryStream ms = new();
-            await DoEncodeAsync(ms);
-            ms.Position = 0;
-            await ms.CopyToAsync(stream, configuration.StreamProcessingBufferSize, cancellationToken)
-                    .ConfigureAwait(false);
-        }
-
-        Task DoEncodeAsync(Stream innerStream)
-        {
-            try
-            {
-                encoder.Encode(image, innerStream, cancellationToken);
-                return Task.CompletedTask;
-            }
-            catch (OperationCanceledException)
-            {
-                return Task.FromCanceled(cancellationToken);
-            }
-            catch (Exception ex)
-            {
-                return Task.FromException(ex);
-            }
-        }
-    }
-
-    public static void Encode<TPixel>(
-        this IImageEncoderInternals encoder,
-        Image<TPixel> image,
-        Stream stream)
-        where TPixel : unmanaged, IPixel<TPixel>
-        => encoder.Encode(image, stream, default);
-}

src/ImageSharp/Formats/ImageFormatManager.cs

@@ -17,9 +17,9 @@ public class ImageFormatManager
     private static readonly object HashLock = new();
 
     /// <summary>
-    /// The list of supported <see cref="ImageEncoder"/> keyed to mime types.
+    /// The list of supported <see cref="IImageEncoder"/> keyed to mime types.
     /// </summary>
-    private readonly ConcurrentDictionary<IImageFormat, ImageEncoder> mimeTypeEncoders = new();
+    private readonly ConcurrentDictionary<IImageFormat, IImageEncoder> mimeTypeEncoders = new();
 
     /// <summary>
     /// The list of supported <see cref="IImageDecoder"/> keyed to mime types.
@@ -64,9 +64,9 @@ public class ImageFormatManager
     internal IEnumerable<KeyValuePair<IImageFormat, IImageDecoder>> ImageDecoders => this.mimeTypeDecoders;
 
     /// <summary>
-    /// Gets the currently registered <see cref="ImageEncoder"/>s.
+    /// Gets the currently registered <see cref="IImageEncoder"/>s.
     /// </summary>
-    internal IEnumerable<KeyValuePair<IImageFormat, ImageEncoder>> ImageEncoders => this.mimeTypeEncoders;
+    internal IEnumerable<KeyValuePair<IImageFormat, IImageEncoder>> ImageEncoders => this.mimeTypeEncoders;
 
     /// <summary>
     /// Registers a new format provider.
@@ -117,7 +117,7 @@ public class ImageFormatManager
     /// </summary>
     /// <param name="imageFormat">The image format to register the encoder for.</param>
     /// <param name="encoder">The encoder to use,</param>
-    public void SetEncoder(IImageFormat imageFormat, ImageEncoder encoder)
+    public void SetEncoder(IImageFormat imageFormat, IImageEncoder encoder)
     {
         Guard.NotNull(imageFormat, nameof(imageFormat));
         Guard.NotNull(encoder, nameof(encoder));
@@ -172,12 +172,12 @@ public class ImageFormatManager
     /// For the specified mime type find the encoder.
     /// </summary>
     /// <param name="format">The format to discover</param>
-    /// <returns>The <see cref="ImageEncoder"/> if found otherwise null</returns>
+    /// <returns>The <see cref="IImageEncoder"/> if found otherwise null</returns>
-    public ImageEncoder FindEncoder(IImageFormat format)
+    public IImageEncoder FindEncoder(IImageFormat format)
     {
         Guard.NotNull(format, nameof(format));
 
-        return this.mimeTypeEncoders.TryGetValue(format, out ImageEncoder encoder)
+        return this.mimeTypeEncoders.TryGetValue(format, out IImageEncoder encoder)
             ? encoder
             : null;
     }

src/ImageSharp/Formats/Jpeg/JpegEncoder.cs

@@ -6,7 +6,7 @@ namespace SixLabors.ImageSharp.Formats.Jpeg;
 /// <summary>
 /// Encoder for writing the data image to a stream in jpeg format.
 /// </summary>
-public sealed class JpegEncoder : ImageEncoder
+public sealed class JpegEncoder : SynchronousImageEncoder
 {
     /// <summary>
     /// Backing field for <see cref="Quality"/>.
@@ -48,16 +48,9 @@ public sealed class JpegEncoder : ImageEncoder
     public JpegEncodingColor? ColorType { get; init; }
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         JpegEncoderCore encoder = new(this);
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        JpegEncoderCore encoder = new(this);
-        return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Formats/Pbm/PbmEncoder.cs

@@ -29,7 +29,7 @@ namespace SixLabors.ImageSharp.Formats.Pbm;
 /// </para>
 /// The specification of these images is found at <seealso href="http://netpbm.sourceforge.net/doc/pnm.html"/>.
 /// </summary>
-public sealed class PbmEncoder : ImageEncoder
+public sealed class PbmEncoder : SynchronousImageEncoder
 {
     /// <summary>
     /// Gets the encoding of the pixels.
@@ -42,21 +42,14 @@ public sealed class PbmEncoder : ImageEncoder
     public PbmColorType? ColorType { get; init; }
 
     /// <summary>
-    /// Gets the Data Type of the pixel components.
+    /// Gets the data type of the pixel components.
     /// </summary>
     public PbmComponentType? ComponentType { get; init; }
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         PbmEncoderCore encoder = new(image.GetConfiguration(), this);
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        PbmEncoderCore encoder = new(image.GetConfiguration(), this);
-        return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Formats/Png/PngEncoder.cs

@@ -74,19 +74,9 @@ public class PngEncoder : QuantizingImageEncoder
     public PngTransparentColorMode TransparentColorMode { get; init; }
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         using PngEncoderCore encoder = new(image.GetMemoryAllocator(), image.GetConfiguration(), this);
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override async Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        // The introduction of a local variable that refers to an object the implements
-        // IDisposable means you must use async/await, where the compiler generates the
-        // state machine and a continuation.
-        using PngEncoderCore encoder = new(image.GetMemoryAllocator(), image.GetConfiguration(), this);
-        await encoder.EncodeAsync(image, stream, cancellationToken).ConfigureAwait(false);
     }
 }

src/ImageSharp/Formats/QuantizingImageEncoder.cs

@@ -0,0 +1,23 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+using SixLabors.ImageSharp.Processing;
+using SixLabors.ImageSharp.Processing.Processors.Quantization;
+
+namespace SixLabors.ImageSharp.Formats;
+
+/// <summary>
+/// Acts as a base class for all image encoders that allow color palette generation via quantization.
+/// </summary>
+public abstract class QuantizingImageEncoder : SynchronousImageEncoder
+{
+    /// <summary>
+    /// Gets the quantizer used to generate the color palette.
+    /// </summary>
+    public IQuantizer Quantizer { get; init; } = KnownQuantizers.Octree;
+
+    /// <summary>
+    /// Gets the <see cref="IPixelSamplingStrategy"/> used for quantization when building color palettes.
+    /// </summary>
+    public IPixelSamplingStrategy PixelSamplingStrategy { get; init; } = new DefaultPixelSamplingStrategy();
+}

src/ImageSharp/Formats/SynchronousImageEncoder.cs

@@ -0,0 +1,94 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+using SixLabors.ImageSharp.Advanced;
+using SixLabors.ImageSharp.IO;
+using SixLabors.ImageSharp.PixelFormats;
+
+namespace SixLabors.ImageSharp.Formats;
+
+/// <summary>
+/// Acts as a base class for image encoders.
+/// Types that inherit this encoder are required to implement cancellable synchronous encoding operations only.
+/// </summary>
+public abstract class SynchronousImageEncoder : IImageEncoder
+{
+    /// <inheritdoc/>
+    public bool SkipMetadata { get; init; }
+
+    /// <inheritdoc/>
+    public void Encode<TPixel>(Image<TPixel> image, Stream stream)
+        where TPixel : unmanaged, IPixel<TPixel>
+         => this.EncodeWithSeekableStream(image, stream, default);
+
+    /// <inheritdoc/>
+    public Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+        where TPixel : unmanaged, IPixel<TPixel>
+        => this.EncodeWithSeekableStreamAsync(image, stream, cancellationToken);
+
+    /// <summary>
+    /// Encodes the image to the specified stream from the <see cref="Image{TPixel}" />.
+    /// </summary>
+    /// <remarks>
+    /// This method is designed to support the ImageSharp internal infrastructure and is not recommended for direct use.
+    /// </remarks>
+    /// <typeparam name="TPixel">The pixel format.</typeparam>
+    /// <param name="image">The <see cref="Image{TPixel}" /> to encode from.</param>
+    /// <param name="stream">The <see cref="Stream" /> to encode the image data to.</param>
+    /// <param name="cancellationToken">The token to monitor for cancellation requests.</param>
+    protected abstract void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+        where TPixel : unmanaged, IPixel<TPixel>;
+
+    private void EncodeWithSeekableStream<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+        where TPixel : unmanaged, IPixel<TPixel>
+    {
+        Configuration configuration = image.GetConfiguration();
+        if (stream.CanSeek)
+        {
+            this.Encode(image, stream, cancellationToken);
+        }
+        else
+        {
+            using ChunkedMemoryStream ms = new(configuration.MemoryAllocator);
+            this.Encode(image, stream, cancellationToken);
+            ms.Position = 0;
+            ms.CopyTo(stream, configuration.StreamProcessingBufferSize);
+        }
+    }
+
+    private async Task EncodeWithSeekableStreamAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+        where TPixel : unmanaged, IPixel<TPixel>
+    {
+        Configuration configuration = image.GetConfiguration();
+        if (stream.CanSeek)
+        {
+            await DoEncodeAsync(stream).ConfigureAwait(false);
+        }
+        else
+        {
+            using ChunkedMemoryStream ms = new(configuration.MemoryAllocator);
+            await DoEncodeAsync(ms);
+            ms.Position = 0;
+            await ms.CopyToAsync(stream, configuration.StreamProcessingBufferSize, cancellationToken)
+                    .ConfigureAwait(false);
+        }
+
+        Task DoEncodeAsync(Stream innerStream)
+        {
+            try
+            {
+                // TODO: Are synchronous IO writes OK? We avoid reads.
+                this.Encode(image, innerStream, cancellationToken);
+                return Task.CompletedTask;
+            }
+            catch (OperationCanceledException)
+            {
+                return Task.FromCanceled(cancellationToken);
+            }
+            catch (Exception ex)
+            {
+                return Task.FromException(ex);
+            }
+        }
+    }
+}

src/ImageSharp/Formats/Tga/TgaEncoder.cs

@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.Formats.Tga;
 /// <summary>
 /// Image encoder for writing an image to a stream as a targa truevision image.
 /// </summary>
-public sealed class TgaEncoder : ImageEncoder
+public sealed class TgaEncoder : SynchronousImageEncoder
 {
     /// <summary>
     /// Gets the number of bits per pixel.
@@ -21,16 +21,9 @@ public sealed class TgaEncoder : ImageEncoder
     public TgaCompression Compression { get; init; } = TgaCompression.RunLength;
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         TgaEncoderCore encoder = new(this, image.GetMemoryAllocator());
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        TgaEncoderCore encoder = new(this, image.GetMemoryAllocator());
-        return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Formats/Tiff/TiffEncoder.cs

@@ -40,16 +40,9 @@ public class TiffEncoder : QuantizingImageEncoder
     public TiffPredictor? HorizontalPredictor { get; init; }
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         TiffEncoderCore encode = new(this, image.GetMemoryAllocator());
-        encode.Encode(image, stream);
+        encode.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        TiffEncoderCore encoder = new(this, image.GetMemoryAllocator());
-        return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Formats/Webp/WebpEncoder.cs

@@ -8,7 +8,7 @@ namespace SixLabors.ImageSharp.Formats.Webp;
 /// <summary>
 /// Image encoder for writing an image to a stream in the Webp format.
 /// </summary>
-public sealed class WebpEncoder : ImageEncoder
+public sealed class WebpEncoder : SynchronousImageEncoder
 {
     /// <summary>
     /// Gets the webp file format used. Either lossless or lossy.
@@ -80,16 +80,9 @@ public sealed class WebpEncoder : ImageEncoder
     public int NearLosslessQuality { get; init; } = 100;
 
     /// <inheritdoc/>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
     {
         WebpEncoderCore encoder = new(this, image.GetMemoryAllocator());
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <inheritdoc/>
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        WebpEncoderCore encoder = new(this, image.GetMemoryAllocator());
-        return encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

src/ImageSharp/Image.cs

@@ -101,7 +101,7 @@ public abstract partial class Image : IImage, IConfigurationProvider
     /// <param name="stream">The stream to save the image to.</param>
     /// <param name="encoder">The encoder to save the image with.</param>
     /// <exception cref="ArgumentNullException">Thrown if the stream or encoder is null.</exception>
-    public void Save(Stream stream, ImageEncoder encoder)
+    public void Save(Stream stream, IImageEncoder encoder)
     {
         Guard.NotNull(stream, nameof(stream));
         Guard.NotNull(encoder, nameof(encoder));
@@ -118,7 +118,7 @@ public abstract partial class Image : IImage, IConfigurationProvider
     /// <param name="cancellationToken">The token to monitor for cancellation requests.</param>
     /// <exception cref="ArgumentNullException">Thrown if the stream or encoder is null.</exception>
     /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
-    public Task SaveAsync(Stream stream, ImageEncoder encoder, CancellationToken cancellationToken = default)
+    public Task SaveAsync(Stream stream, IImageEncoder encoder, CancellationToken cancellationToken = default)
     {
         Guard.NotNull(stream, nameof(stream));
         Guard.NotNull(encoder, nameof(encoder));
@@ -189,11 +189,11 @@ public abstract partial class Image : IImage, IConfigurationProvider
 
     private class EncodeVisitor : IImageVisitor, IImageVisitorAsync
     {
-        private readonly ImageEncoder encoder;
+        private readonly IImageEncoder encoder;
 
         private readonly Stream stream;
 
-        public EncodeVisitor(ImageEncoder encoder, Stream stream)
+        public EncodeVisitor(IImageEncoder encoder, Stream stream)
         {
             this.encoder = encoder;
             this.stream = stream;

src/ImageSharp/ImageExtensions.cs

@@ -43,14 +43,12 @@ public static partial class ImageExtensions
     /// <param name="encoder">The encoder to save the image with.</param>
     /// <exception cref="ArgumentNullException">The path is null.</exception>
     /// <exception cref="ArgumentNullException">The encoder is null.</exception>
-    public static void Save(this Image source, string path, ImageEncoder encoder)
+    public static void Save(this Image source, string path, IImageEncoder encoder)
     {
         Guard.NotNull(path, nameof(path));
         Guard.NotNull(encoder, nameof(encoder));
-        using (Stream fs = source.GetConfiguration().FileSystem.Create(path))
+        using Stream fs = source.GetConfiguration().FileSystem.Create(path);
-        {
+        source.Save(fs, encoder);
-            source.Save(fs, encoder);
-        }
     }
 
     /// <summary>
@@ -66,7 +64,7 @@ public static partial class ImageExtensions
     public static async Task SaveAsync(
         this Image source,
         string path,
-        ImageEncoder encoder,
+        IImageEncoder encoder,
         CancellationToken cancellationToken = default)
     {
         Guard.NotNull(path, nameof(path));
@@ -96,14 +94,14 @@ public static partial class ImageExtensions
             throw new NotSupportedException("Cannot write to the stream.");
         }
 
-        ImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
+        IImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
 
         if (encoder is null)
         {
             StringBuilder sb = new();
             sb.AppendLine("No encoder was found for the provided mime type. Registered encoders include:");
 
-            foreach (KeyValuePair<IImageFormat, ImageEncoder> val in source.GetConfiguration().ImageFormatsManager.ImageEncoders)
+            foreach (KeyValuePair<IImageFormat, IImageEncoder> val in source.GetConfiguration().ImageFormatsManager.ImageEncoders)
             {
                 sb.AppendFormat(CultureInfo.InvariantCulture, " - {0} : {1}{2}", val.Key.Name, val.Value.GetType().Name, Environment.NewLine);
             }
@@ -140,14 +138,14 @@ public static partial class ImageExtensions
             throw new NotSupportedException("Cannot write to the stream.");
         }
 
-        ImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
+        IImageEncoder encoder = source.GetConfiguration().ImageFormatsManager.FindEncoder(format);
 
         if (encoder is null)
         {
             StringBuilder sb = new();
             sb.AppendLine("No encoder was found for the provided mime type. Registered encoders include:");
 
-            foreach (KeyValuePair<IImageFormat, ImageEncoder> val in source.GetConfiguration().ImageFormatsManager.ImageEncoders)
+            foreach (KeyValuePair<IImageFormat, IImageEncoder> val in source.GetConfiguration().ImageFormatsManager.ImageEncoders)
             {
                 sb.AppendFormat(CultureInfo.InvariantCulture, " - {0} : {1}{2}", val.Key.Name, val.Value.GetType().Name, Environment.NewLine);
             }

tests/ImageSharp.Tests/Formats/ImageFormatManagerTests.cs

@@ -56,7 +56,7 @@ public class ImageFormatManagerTests
     [Fact]
     public void RegisterNullMimeTypeEncoder()
     {
-        Assert.Throws<ArgumentNullException>(() => this.DefaultFormatsManager.SetEncoder(null, new Mock<ImageEncoder>().Object));
+        Assert.Throws<ArgumentNullException>(() => this.DefaultFormatsManager.SetEncoder(null, new Mock<IImageEncoder>().Object));
         Assert.Throws<ArgumentNullException>(() => this.DefaultFormatsManager.SetEncoder(BmpFormat.Instance, null));
         Assert.Throws<ArgumentNullException>(() => this.DefaultFormatsManager.SetEncoder(null, null));
     }
@@ -72,14 +72,14 @@ public class ImageFormatManagerTests
     [Fact]
     public void RegisterMimeTypeEncoderReplacesLast()
     {
-        ImageEncoder encoder1 = new Mock<ImageEncoder>().Object;
+        IImageEncoder encoder1 = new Mock<IImageEncoder>().Object;
         this.FormatsManagerEmpty.SetEncoder(TestFormat.GlobalTestFormat, encoder1);
-        ImageEncoder found = this.FormatsManagerEmpty.FindEncoder(TestFormat.GlobalTestFormat);
+        IImageEncoder found = this.FormatsManagerEmpty.FindEncoder(TestFormat.GlobalTestFormat);
         Assert.Equal(encoder1, found);
 
-        ImageEncoder encoder2 = new Mock<ImageEncoder>().Object;
+        IImageEncoder encoder2 = new Mock<IImageEncoder>().Object;
         this.FormatsManagerEmpty.SetEncoder(TestFormat.GlobalTestFormat, encoder2);
-        ImageEncoder found2 = this.FormatsManagerEmpty.FindEncoder(TestFormat.GlobalTestFormat);
+        IImageEncoder found2 = this.FormatsManagerEmpty.FindEncoder(TestFormat.GlobalTestFormat);
         Assert.Equal(encoder2, found2);
         Assert.NotEqual(found, found2);
     }

tests/ImageSharp.Tests/Image/ImageSaveTests.cs

@@ -16,8 +16,8 @@ public class ImageSaveTests : IDisposable
 {
     private readonly Image<Rgba32> image;
     private readonly Mock<IFileSystem> fileSystem;
-    private readonly Mock<ImageEncoder> encoder;
+    private readonly Mock<IImageEncoder> encoder;
-    private readonly Mock<ImageEncoder> encoderNotInFormat;
+    private readonly Mock<IImageEncoder> encoderNotInFormat;
     private IImageFormatDetector localMimeTypeDetector;
     private Mock<IImageFormat> localImageFormat;
 
@@ -27,9 +27,9 @@ public class ImageSaveTests : IDisposable
         this.localImageFormat.Setup(x => x.FileExtensions).Returns(new[] { "png" });
         this.localMimeTypeDetector = new MockImageFormatDetector(this.localImageFormat.Object);
 
-        this.encoder = new Mock<ImageEncoder>();
+        this.encoder = new Mock<IImageEncoder>();
 
-        this.encoderNotInFormat = new Mock<ImageEncoder>();
+        this.encoderNotInFormat = new Mock<IImageEncoder>();
 
         this.fileSystem = new Mock<IFileSystem>();
         var config = new Configuration

tests/ImageSharp.Tests/Image/ImageTests.Save.cs

@@ -68,7 +68,7 @@ public partial class ImageTests
         {
             using var image = new Image<Rgba32>(5, 5);
             image.Dispose();
-            ImageEncoder encoder = Mock.Of<ImageEncoder>();
+            IImageEncoder encoder = Mock.Of<IImageEncoder>();
             using (var stream = new MemoryStream())
             {
                 Assert.Throws<ObjectDisposedException>(() => image.Save(stream, encoder));

tests/ImageSharp.Tests/Image/ImageTests.SaveAsync.cs

@@ -102,7 +102,7 @@ public partial class ImageTests
         {
             var image = new Image<Rgba32>(5, 5);
             image.Dispose();
-            ImageEncoder encoder = Mock.Of<ImageEncoder>();
+            IImageEncoder encoder = Mock.Of<IImageEncoder>();
             using (var stream = new MemoryStream())
             {
                 await Assert.ThrowsAsync<ObjectDisposedException>(async () => await image.SaveAsync(stream, encoder));
@@ -120,7 +120,7 @@ public partial class ImageTests
         {
             using (var image = new Image<Rgba32>(5, 5))
             {
-                ImageEncoder encoder = image.DetectEncoder(filename);
+                IImageEncoder encoder = image.DetectEncoder(filename);
                 using (var stream = new MemoryStream())
                 {
                     var asyncStream = new AsyncStreamWrapper(stream, () => false);

tests/ImageSharp.Tests/Image/ImageTests.cs

@@ -328,7 +328,7 @@ public partial class ImageTests
         public void KnownExtension_ReturnsEncoder()
         {
             using var image = new Image<L8>(1, 1);
-            ImageEncoder encoder = image.DetectEncoder("dummy.png");
+            IImageEncoder encoder = image.DetectEncoder("dummy.png");
             Assert.NotNull(encoder);
             Assert.IsType<PngEncoder>(encoder);
         }

tests/ImageSharp.Tests/Image/LargeImageIntegrationTests.cs

@@ -55,7 +55,7 @@ public class LargeImageIntegrationTests
 
             Configuration configuration = Configuration.Default.Clone();
             configuration.PreferContiguousImageBuffers = true;
-            ImageEncoder encoder = configuration.ImageFormatsManager.FindEncoder(
+            IImageEncoder encoder = configuration.ImageFormatsManager.FindEncoder(
                 configuration.ImageFormatsManager.FindFormatByFileExtension(formatInner));
             string dir = TestEnvironment.CreateOutputDirectory(".Temp");
             string path = Path.Combine(dir, $"{Guid.NewGuid()}.{formatInner}");

tests/ImageSharp.Tests/Metadata/Profiles/XMP/XmpProfileTests.cs

@@ -242,7 +242,7 @@ public class XmpProfileTests
         return profile;
     }
 
-    private static Image<Rgba32> WriteAndRead(Image<Rgba32> image, ImageEncoder encoder)
+    private static Image<Rgba32> WriteAndRead(Image<Rgba32> image, IImageEncoder encoder)
     {
         using (var memStream = new MemoryStream())
         {

tests/ImageSharp.Tests/TestFormat.cs

@@ -233,7 +233,7 @@ public class TestFormat : IConfigurationModule, IImageFormat
         public DecoderOptions GeneralOptions { get; init; } = DecoderOptions.Default;
     }
 
-    public class TestEncoder : ImageEncoder
+    public class TestEncoder : IImageEncoder
     {
         private readonly TestFormat testFormat;
 
@@ -243,13 +243,17 @@ public class TestFormat : IConfigurationModule, IImageFormat
 
         public IEnumerable<string> FileExtensions => this.testFormat.SupportedExtensions;
 
-        public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+        public bool SkipMetadata { get; init; }
+
+        public void Encode<TPixel>(Image<TPixel> image, Stream stream)
+            where TPixel : unmanaged, IPixel<TPixel>
         {
             // TODO record this happened so we can verify it.
         }
 
-        public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+        public Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-           => Task.CompletedTask;  // TODO record this happened so we can verify it.
+            where TPixel : unmanaged, IPixel<TPixel>
+            => Task.CompletedTask;  // TODO record this happened so we can verify it.
     }
 
     public struct TestPixelForAgnosticDecode : IPixel<TestPixelForAgnosticDecode>

tests/ImageSharp.Tests/TestUtilities/ImagingTestCaseUtility.cs

@@ -158,7 +158,7 @@ public class ImagingTestCaseUtility
     public string SaveTestOutputFile(
         Image image,
         string extension = null,
-        ImageEncoder encoder = null,
+        IImageEncoder encoder = null,
         object testOutputDetails = null,
         bool appendPixelTypeToFileName = true,
         bool appendSourceFileOrDescription = true)
@@ -203,7 +203,7 @@ public class ImagingTestCaseUtility
     public string[] SaveTestOutputFileMultiFrame<TPixel>(
         Image<TPixel> image,
         string extension = "png",
-        ImageEncoder encoder = null,
+        IImageEncoder encoder = null,
         object testOutputDetails = null,
         bool appendPixelTypeToFileName = true)
         where TPixel : unmanaged, IPixel<TPixel>

tests/ImageSharp.Tests/TestUtilities/ReferenceCodecs/ImageSharpPngEncoderWithDefaultConfiguration.cs

@@ -1,7 +1,6 @@
 // Copyright (c) Six Labors.
 // Licensed under the Six Labors Split License.
 
-using SixLabors.ImageSharp.Formats;
 using SixLabors.ImageSharp.Formats.Png;
 using SixLabors.ImageSharp.Memory;
 
@@ -13,38 +12,13 @@ namespace SixLabors.ImageSharp.Tests.TestUtilities.ReferenceCodecs;
 /// </summary>
 public sealed class ImageSharpPngEncoderWithDefaultConfiguration : PngEncoder
 {
-    /// <summary>
+    /// <inheritdoc/>
-    /// Encodes the image to the specified stream from the <see cref="Image{TPixel}"/>.
+    protected override void Encode<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    /// </summary>
-    /// <typeparam name="TPixel">The pixel format.</typeparam>
-    /// <param name="image">The <see cref="Image{TPixel}"/> to encode from.</param>
-    /// <param name="stream">The <see cref="Stream"/> to encode the image data to.</param>
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
     {
         Configuration configuration = Configuration.Default;
         MemoryAllocator allocator = configuration.MemoryAllocator;
 
         using PngEncoderCore encoder = new(allocator, configuration, this);
-        encoder.Encode(image, stream);
+        encoder.Encode(image, stream, cancellationToken);
-    }
-
-    /// <summary>
-    /// Encodes the image to the specified stream from the <see cref="Image{TPixel}"/>.
-    /// </summary>
-    /// <typeparam name="TPixel">The pixel format.</typeparam>
-    /// <param name="image">The <see cref="Image{TPixel}"/> to encode from.</param>
-    /// <param name="stream">The <see cref="Stream"/> to encode the image data to.</param>
-    /// <param name="cancellationToken">The token to monitor for cancellation requests.</param>
-    /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
-    public override async Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
-    {
-        Configuration configuration = Configuration.Default;
-        MemoryAllocator allocator = configuration.MemoryAllocator;
-
-        // The introduction of a local variable that refers to an object the implements
-        // IDisposable means you must use async/await, where the compiler generates the
-        // state machine and a continuation.
-        using PngEncoderCore encoder = new(allocator, configuration, this);
-        await encoder.EncodeAsync(image, stream, cancellationToken);
     }
 }

tests/ImageSharp.Tests/TestUtilities/ReferenceCodecs/SystemDrawingReferenceEncoder.cs

@@ -3,10 +3,11 @@
 
 using System.Drawing.Imaging;
 using SixLabors.ImageSharp.Formats;
+using SixLabors.ImageSharp.PixelFormats;
 
 namespace SixLabors.ImageSharp.Tests.TestUtilities.ReferenceCodecs;
 
-public class SystemDrawingReferenceEncoder : ImageEncoder
+public class SystemDrawingReferenceEncoder : IImageEncoder
 {
     private readonly ImageFormat imageFormat;
 
@@ -17,13 +18,17 @@ public class SystemDrawingReferenceEncoder : ImageEncoder
 
     public static SystemDrawingReferenceEncoder Bmp { get; } = new SystemDrawingReferenceEncoder(ImageFormat.Bmp);
 
-    public override void Encode<TPixel>(Image<TPixel> image, Stream stream)
+    public bool SkipMetadata { get; init; }
+
+    public void Encode<TPixel>(Image<TPixel> image, Stream stream)
+        where TPixel : unmanaged, IPixel<TPixel>
     {
         using System.Drawing.Bitmap sdBitmap = SystemDrawingBridge.To32bppArgbSystemDrawingBitmap(image);
         sdBitmap.Save(stream, this.imageFormat);
     }
 
-    public override Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+    public Task EncodeAsync<TPixel>(Image<TPixel> image, Stream stream, CancellationToken cancellationToken)
+        where TPixel : unmanaged, IPixel<TPixel>
     {
         using (System.Drawing.Bitmap sdBitmap = SystemDrawingBridge.To32bppArgbSystemDrawingBitmap(image))
         {

tests/ImageSharp.Tests/TestUtilities/TestEnvironment.Formats.cs

@@ -26,7 +26,7 @@ public static partial class TestEnvironment
         return Configuration.ImageFormatsManager.FindDecoder(format);
     }
 
-    internal static ImageEncoder GetReferenceEncoder(string filePath)
+    internal static IImageEncoder GetReferenceEncoder(string filePath)
     {
         IImageFormat format = GetImageFormat(filePath);
         return Configuration.ImageFormatsManager.FindEncoder(format);
@@ -43,7 +43,7 @@ public static partial class TestEnvironment
         this Configuration cfg,
         IImageFormat imageFormat,
         IImageDecoder decoder,
-        ImageEncoder encoder,
+        IImageEncoder encoder,
         IImageFormatDetector detector)
     {
         cfg.ImageFormatsManager.SetDecoder(imageFormat, decoder);
@@ -61,8 +61,8 @@ public static partial class TestEnvironment
             new WebpConfigurationModule(),
             new TiffConfigurationModule());
 
-        ImageEncoder pngEncoder = IsWindows ? SystemDrawingReferenceEncoder.Png : new ImageSharpPngEncoderWithDefaultConfiguration();
+        IImageEncoder pngEncoder = IsWindows ? SystemDrawingReferenceEncoder.Png : new ImageSharpPngEncoderWithDefaultConfiguration();
-        ImageEncoder bmpEncoder = IsWindows ? SystemDrawingReferenceEncoder.Bmp : new BmpEncoder();
+        IImageEncoder bmpEncoder = IsWindows ? SystemDrawingReferenceEncoder.Bmp : new BmpEncoder();
 
         // Magick codecs should work on all platforms
         cfg.ConfigureCodecs(

tests/ImageSharp.Tests/TestUtilities/TestImageExtensions.cs

@@ -30,7 +30,7 @@ public static class TestImageExtensions
         string extension = "png",
         bool appendPixelTypeToFileName = true,
         bool appendSourceFileOrDescription = true,
-        ImageEncoder encoder = null)
+        IImageEncoder encoder = null)
         => image.DebugSave(
             provider,
             (object)testOutputDetails,
@@ -57,7 +57,7 @@ public static class TestImageExtensions
         string extension = "png",
         bool appendPixelTypeToFileName = true,
         bool appendSourceFileOrDescription = true,
-        ImageEncoder encoder = null)
+        IImageEncoder encoder = null)
     {
         if (TestEnvironment.RunsWithCodeCoverage)
         {
@@ -77,7 +77,7 @@ public static class TestImageExtensions
     public static void DebugSave(
         this Image image,
         ITestImageProvider provider,
-        ImageEncoder encoder,
+        IImageEncoder encoder,
         FormattableString testOutputDetails,
         bool appendPixelTypeToFileName = true)
         => image.DebugSave(provider, encoder, (object)testOutputDetails, appendPixelTypeToFileName);
@@ -93,7 +93,7 @@ public static class TestImageExtensions
     public static void DebugSave(
         this Image image,
         ITestImageProvider provider,
-        ImageEncoder encoder,
+        IImageEncoder encoder,
         object testOutputDetails = null,
         bool appendPixelTypeToFileName = true)
         => provider.Utility.SaveTestOutputFile(
@@ -664,7 +664,7 @@ public static class TestImageExtensions
         ITestImageProvider provider,
         string extension,
         object testOutputDetails,
-        ImageEncoder encoder,
+        IImageEncoder encoder,
         ImageComparer customComparer = null,
         bool appendPixelTypeToFileName = true,
         string referenceImageExtension = null,

tests/ImageSharp.Tests/TestUtilities/Tests/TestEnvironmentTests.cs

@@ -62,7 +62,7 @@ public class TestEnvironmentTests
             return;
         }
 
-        ImageEncoder encoder = TestEnvironment.GetReferenceEncoder(fileName);
+        IImageEncoder encoder = TestEnvironment.GetReferenceEncoder(fileName);
         Assert.IsType(expectedEncoderType, encoder);
     }
 
@@ -96,7 +96,7 @@ public class TestEnvironmentTests
             return;
         }
 
-        ImageEncoder encoder = TestEnvironment.GetReferenceEncoder(fileName);
+        IImageEncoder encoder = TestEnvironment.GetReferenceEncoder(fileName);
         Assert.IsType(expectedEncoderType, encoder);
     }