Rename properties and add metadata tests

src/ImageSharp/Formats/Png/PngDecoderCore.cs

@@ -1258,7 +1258,7 @@ internal sealed class PngDecoderCore : IImageDecoderInternals
     {
         this.animationControl = AnimationControl.Parse(data);
 
-        pngMetadata.NumberPlays = this.animationControl.NumberPlays;
+        pngMetadata.RepeatCount = this.animationControl.NumberPlays;
     }
 
     /// <summary>

src/ImageSharp/Formats/Png/PngEncoderCore.cs

@@ -176,7 +176,7 @@ internal sealed class PngEncoderCore : IImageEncoderInternals, IDisposable
 
         if (image.Frames.Count > 1)
         {
-            this.WriteAnimationControlChunk(stream, image.Frames.Count, pngMetadata.NumberPlays);
+            this.WriteAnimationControlChunk(stream, image.Frames.Count, pngMetadata.RepeatCount);
 
             // TODO: We should attempt to optimize the output by clipping the indexed result to
             // non-transparent bounds. That way we can assign frame control bounds and encode
@@ -996,8 +996,8 @@ internal sealed class PngEncoderCore : IImageEncoderInternals, IDisposable
             height: (uint)imageFrame.Height,
             xOffset: 0,
             yOffset: 0,
-            delayNumerator: frameMetadata.DelayNumerator,
-            delayDenominator: frameMetadata.DelayDenominator,
+            delayNumerator: (ushort)frameMetadata.FrameDelay.Numerator,
+            delayDenominator: (ushort)frameMetadata.FrameDelay.Denominator,
             disposeOperation: frameMetadata.DisposalMethod,
             blendOperation: frameMetadata.BlendMethod);
 

src/ImageSharp/Formats/Png/PngFrameMetadata.cs

@@ -23,21 +23,18 @@ public class PngFrameMetadata : IDeepCloneable
     /// <param name="other">The metadata to create an instance from.</param>
     private PngFrameMetadata(PngFrameMetadata other)
     {
-        this.DelayNumerator = other.DelayNumerator;
-        this.DelayDenominator = other.DelayDenominator;
+        this.FrameDelay = other.FrameDelay;
         this.DisposalMethod = other.DisposalMethod;
         this.BlendMethod = other.BlendMethod;
     }
 
     /// <summary>
-    /// Gets or sets the frame delay fraction numerator
+    /// Gets or sets the frame delay for animated images.
+    /// If not 0, when utilized in Png animation, this field specifies the number of hundredths (1/100) of a second to
+    /// wait before continuing with the processing of the Data Stream.
+    /// The clock starts ticking immediately after the graphic is rendered.
     /// </summary>
-    public ushort DelayNumerator { get; set; }
-
-    /// <summary>
-    /// Gets or sets the frame delay fraction denominator
-    /// </summary>
-    public ushort DelayDenominator { get; set; }
+    public Rational FrameDelay { get; set; }
 
     /// <summary>
     /// Gets or sets the type of frame area disposal to be done after rendering this frame
@@ -55,8 +52,7 @@ public class PngFrameMetadata : IDeepCloneable
     /// <param name="frameControl">The chunk to create an instance from.</param>
     internal void FromChunk(in FrameControl frameControl)
     {
-        this.DelayNumerator = frameControl.DelayNumerator;
-        this.DelayDenominator = frameControl.DelayDenominator;
+        this.FrameDelay = new Rational(frameControl.DelayNumerator, frameControl.DelayDenominator);
         this.DisposalMethod = frameControl.DisposeOperation;
         this.BlendMethod = frameControl.BlendOperation;
     }

src/ImageSharp/Formats/Png/PngMetadata.cs

@@ -29,7 +29,7 @@ public class PngMetadata : IDeepCloneable
         this.Gamma = other.Gamma;
         this.InterlaceMethod = other.InterlaceMethod;
         this.TransparentColor = other.TransparentColor;
-        this.NumberPlays = other.NumberPlays;
+        this.RepeatCount = other.RepeatCount;
 
         if (other.ColorTable?.Length > 0)
         {
@@ -80,9 +80,9 @@ public class PngMetadata : IDeepCloneable
     public IList<PngTextData> TextData { get; set; } = new List<PngTextData>();
 
     /// <summary>
-    /// Gets or sets the number of times to loop this APNG.  0 indicates infinite looping. TODO: RepeatCount!!
+    /// Gets or sets the number of times to loop this APNG.  0 indicates infinite looping.
     /// </summary>
-    public int NumberPlays { get; set; }
+    public int RepeatCount { get; set; }
 
     /// <inheritdoc/>
     public IDeepCloneable DeepClone() => new PngMetadata(this);

src/ImageSharp/Primitives/Rational.cs

@@ -70,7 +70,7 @@ public readonly struct Rational : IEquatable<Rational>
     /// <param name="bestPrecision">Whether to use the best possible precision when parsing the value.</param>
     public Rational(double value, bool bestPrecision)
     {
-        var rational = LongRational.FromDouble(Math.Abs(value), bestPrecision);
+        LongRational rational = LongRational.FromDouble(Math.Abs(value), bestPrecision);
 
         this.Numerator = (uint)rational.Numerator;
         this.Denominator = (uint)rational.Denominator;
@@ -109,7 +109,7 @@ public readonly struct Rational : IEquatable<Rational>
     /// <returns>
     /// The <see cref="Rational"/>.
     /// </returns>
-    public static Rational FromDouble(double value) => new Rational(value, false);
+    public static Rational FromDouble(double value) => new(value, false);
 
     /// <summary>
     /// Converts the specified <see cref="double"/> to an instance of this type.
@@ -119,24 +119,19 @@ public readonly struct Rational : IEquatable<Rational>
     /// <returns>
     /// The <see cref="Rational"/>.
     /// </returns>
-    public static Rational FromDouble(double value, bool bestPrecision) => new Rational(value, bestPrecision);
+    public static Rational FromDouble(double value, bool bestPrecision) => new(value, bestPrecision);
 
     /// <inheritdoc/>
     public override bool Equals(object? obj) => obj is Rational other && this.Equals(other);
 
     /// <inheritdoc/>
     public bool Equals(Rational other)
-    {
-        var left = new LongRational(this.Numerator, this.Denominator);
-        var right = new LongRational(other.Numerator, other.Denominator);
-
-        return left.Equals(right);
-    }
+        => this.Numerator == other.Numerator && this.Denominator == other.Denominator;
 
     /// <inheritdoc/>
     public override int GetHashCode()
     {
-        var self = new LongRational(this.Numerator, this.Denominator);
+        LongRational self = new(this.Numerator, this.Denominator);
         return self.GetHashCode();
     }
 
@@ -169,7 +164,7 @@ public readonly struct Rational : IEquatable<Rational>
     /// <returns>The <see cref="string"/></returns>
     public string ToString(IFormatProvider provider)
     {
-        var rational = new LongRational(this.Numerator, this.Denominator);
+        LongRational rational = new(this.Numerator, this.Denominator);
         return rational.ToString(provider);
     }
 }

tests/ImageSharp.Tests/Formats/Png/PngEncoderTests.cs

@@ -457,8 +457,23 @@ public partial class PngEncoderTests
         using Image<Rgba32> output = Image.Load<Rgba32>(memStream);
         ImageComparer.Exact.VerifySimilarity(output, image);
 
-        // TODO: Additional assertations regarding metadata.
         Assert.Equal(5, image.Frames.Count);
+        Assert.Equal(image.Frames.Count, output.Frames.Count);
+
+        PngMetadata originalMetadata = image.Metadata.GetPngMetadata();
+        PngMetadata outputMetadata = output.Metadata.GetPngMetadata();
+
+        Assert.Equal(originalMetadata.RepeatCount, outputMetadata.RepeatCount);
+
+        for (int i = 0; i < image.Frames.Count; i++)
+        {
+            PngFrameMetadata originalFrameMetadata = image.Frames[i].Metadata.GetPngFrameMetadata();
+            PngFrameMetadata outputFrameMetadata = output.Frames[i].Metadata.GetPngFrameMetadata();
+
+            Assert.Equal(originalFrameMetadata.FrameDelay, outputFrameMetadata.FrameDelay);
+            Assert.Equal(originalFrameMetadata.BlendMethod, outputFrameMetadata.BlendMethod);
+            Assert.Equal(originalFrameMetadata.DisposalMethod, outputFrameMetadata.DisposalMethod);
+        }
     }
 
     [Theory]

tests/ImageSharp.Tests/Formats/Png/PngFrameMetadataTests.cs

@@ -0,0 +1,35 @@
+// Copyright (c) Six Labors.
+// Licensed under the Six Labors Split License.
+
+using SixLabors.ImageSharp.Formats.Png;
+
+namespace SixLabors.ImageSharp.Tests.Formats.Png;
+
+[Trait("Format", "Png")]
+public class PngFrameMetadataTests
+{
+    [Fact]
+    public void CloneIsDeep()
+    {
+        PngFrameMetadata meta = new()
+        {
+            FrameDelay = new(1, 0),
+            DisposalMethod = PngDisposalMethod.Background,
+            BlendMethod = PngBlendMethod.Over,
+        };
+
+        PngFrameMetadata clone = (PngFrameMetadata)meta.DeepClone();
+
+        Assert.True(meta.FrameDelay.Equals(clone.FrameDelay));
+        Assert.True(meta.DisposalMethod.Equals(clone.DisposalMethod));
+        Assert.True(meta.BlendMethod.Equals(clone.BlendMethod));
+
+        clone.FrameDelay = new(2, 1);
+        clone.DisposalMethod = PngDisposalMethod.Previous;
+        clone.BlendMethod = PngBlendMethod.Source;
+
+        Assert.False(meta.FrameDelay.Equals(clone.FrameDelay));
+        Assert.False(meta.DisposalMethod.Equals(clone.DisposalMethod));
+        Assert.False(meta.BlendMethod.Equals(clone.BlendMethod));
+    }
+}

tests/ImageSharp.Tests/Formats/Png/PngMetadataTests.cs

@@ -31,15 +31,25 @@ public class PngMetadataTests
             ColorType = PngColorType.GrayscaleWithAlpha,
             InterlaceMethod = PngInterlaceMode.Adam7,
             Gamma = 2,
-            TextData = new List<PngTextData> { new PngTextData("name", "value", "foo", "bar") }
+            TextData = new List<PngTextData> { new PngTextData("name", "value", "foo", "bar") },
+            RepeatCount = 123
         };
 
         PngMetadata clone = (PngMetadata)meta.DeepClone();
 
+        Assert.True(meta.BitDepth == clone.BitDepth);
+        Assert.True(meta.ColorType == clone.ColorType);
+        Assert.True(meta.InterlaceMethod == clone.InterlaceMethod);
+        Assert.True(meta.Gamma.Equals(clone.Gamma));
+        Assert.False(meta.TextData.Equals(clone.TextData));
+        Assert.True(meta.TextData.SequenceEqual(clone.TextData));
+        Assert.True(meta.RepeatCount == clone.RepeatCount);
+
         clone.BitDepth = PngBitDepth.Bit2;
         clone.ColorType = PngColorType.Palette;
         clone.InterlaceMethod = PngInterlaceMode.None;
         clone.Gamma = 1;
+        clone.RepeatCount = 321;
 
         Assert.False(meta.BitDepth == clone.BitDepth);
         Assert.False(meta.ColorType == clone.ColorType);
@@ -47,6 +57,7 @@ public class PngMetadataTests
         Assert.False(meta.Gamma.Equals(clone.Gamma));
         Assert.False(meta.TextData.Equals(clone.TextData));
         Assert.True(meta.TextData.SequenceEqual(clone.TextData));
+        Assert.False(meta.RepeatCount == clone.RepeatCount);
     }
 
     [Theory]