Add IJxlImageOutput

src/ImageSharp/Formats/Jxl/Processing/Decoder/JxlDecoderCore.cs

@@ -1928,8 +1928,7 @@ internal sealed class JxlDecoderCore : ImageDecoderCore, IDisposable
                             new PixelCallback(
                                 this.imageOutputInitCallback,
                                 this.imageOutputRunCallback,
-                                this.imageOutputDestroyCallback,
-                                this.imageOutputInitOpaque),
+                                this.imageOutputDestroyCallback),
                             this.imageOutBuffer,
                             this.imageOutputSize,
                             dimensions.Width,

src/ImageSharp/Formats/Jxl/Processing/Image/IJxlImageOutput.cs

@@ -0,0 +1,54 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+using SixLabors.ImageSharp.Formats.Jxl.Processing.Primitives;
+
+namespace SixLabors.ImageSharp.Formats.Jxl.Processing.Image;
+
+/// <summary>
+/// Abstracts a way for the codec to output images during decoding.
+/// </summary>
+internal interface IJxlImageOutput : IDisposable
+{
+    /// <summary>
+    /// Gets or sets the pixel format for the output pixels.
+    /// </summary>
+    public JxlPixelFormat PixelFormat { get; set; }
+
+    /// <summary>
+    /// Gets or sets the output bit depth for unsigned data types.
+    /// </summary>
+    public int BitsPerSample { get; set; }
+
+    /// <summary>
+    /// Gets or sets the pixel buffer for image output.
+    /// </summary>
+    public Memory<byte> Buffer { get; set; }
+
+    /// <summary>
+    /// Gets or sets length of a row of image buffer in bytes.
+    /// </summary>
+    public int Stride { get; set; }
+
+    /// <summary>
+    /// Outputs the image.
+    /// </summary>
+    /// <param name="data">Data where the image should be output.</param>
+    /// <param name="x">X offset</param>
+    /// <param name="y">Y offset</param>
+    /// <param name="pixels">Pixels to output.</param>
+    public void Output(
+        Span<byte> data,
+        int x,
+        int y,
+        Span<byte> pixels);
+
+    /// <summary>
+    /// Initializes image data.
+    /// </summary>
+    /// <param name="data">Output image data.</param>
+    /// <param name="numPixelsPerThread">Number of pixels a thread processes.</param>
+    public void Initialize(
+        Span<byte> data,
+        int numPixelsPerThread);
+}

src/ImageSharp/Formats/Jxl/Processing/Primitives/Delegates.cs

@@ -1,25 +0,0 @@
-// Copyright (c) Six Labors.
-// Licensed under the Six Labors Split License.
-
-namespace SixLabors.ImageSharp.Formats.Jxl.Processing.Primitives;
-
-internal delegate void JxlImageOutputCallback(
-    Span<byte> data,
-    int x,
-    int y,
-    int numPixels,
-    Span<byte> pixels);
-
-internal delegate void JxlImageOutputInitializeCallback(
-    Span<byte> data,
-    int numThreads,
-    int numPixelsPerThread);
-
-internal delegate void JxlImageOutputRunCallback(
-    Span<byte> data,
-    int x,
-    int y,
-    int numPixels,
-    Span<byte> pixels);
-
-internal delegate void JxlImageOutputDestroyCallback(Span<byte> data);