ImageSharp/tests/ImageSharp.Tests/Processing/Processors/Quantization/WuQuantizerTests.cs

// Copyright (c) Six Labors.
// Licensed under the Six Labors Split License.

using SixLabors.ImageSharp.PixelFormats;
using SixLabors.ImageSharp.Processing;
using SixLabors.ImageSharp.Processing.Processors.Quantization;

namespace SixLabors.ImageSharp.Tests.Processing.Processors.Quantization;

[Trait("Category", "Processors")]
public class WuQuantizerTests
{
    [Fact]
    public void WuQuantizerConstructor()
    {
        var expected = new QuantizerOptions { MaxColors = 128 };
        var quantizer = new WuQuantizer(expected);

        Assert.Equal(expected.MaxColors, quantizer.Options.MaxColors);
        Assert.Equal(QuantizerConstants.DefaultDither, quantizer.Options.Dither);

        expected = new QuantizerOptions { Dither = null };
        quantizer = new WuQuantizer(expected);
        Assert.Equal(QuantizerConstants.MaxColors, quantizer.Options.MaxColors);
        Assert.Null(quantizer.Options.Dither);

        expected = new QuantizerOptions { Dither = KnownDitherings.Atkinson };
        quantizer = new WuQuantizer(expected);
        Assert.Equal(QuantizerConstants.MaxColors, quantizer.Options.MaxColors);
        Assert.Equal(KnownDitherings.Atkinson, quantizer.Options.Dither);

        expected = new QuantizerOptions { Dither = KnownDitherings.Atkinson, MaxColors = 0 };
        quantizer = new WuQuantizer(expected);
        Assert.Equal(QuantizerConstants.MinColors, quantizer.Options.MaxColors);
        Assert.Equal(KnownDitherings.Atkinson, quantizer.Options.Dither);
    }

    [Fact]
    public void WuQuantizerCanCreateFrameQuantizer()
    {
        var quantizer = new WuQuantizer();
        IQuantizer<Rgba32> frameQuantizer = quantizer.CreatePixelSpecificQuantizer<Rgba32>(Configuration.Default);

        Assert.NotNull(frameQuantizer);
        Assert.NotNull(frameQuantizer.Options);
        Assert.Equal(QuantizerConstants.DefaultDither, frameQuantizer.Options.Dither);
        frameQuantizer.Dispose();

        quantizer = new WuQuantizer(new QuantizerOptions { Dither = null });
        frameQuantizer = quantizer.CreatePixelSpecificQuantizer<Rgba32>(Configuration.Default);

        Assert.NotNull(frameQuantizer);
        Assert.Null(frameQuantizer.Options.Dither);
        frameQuantizer.Dispose();

        quantizer = new WuQuantizer(new QuantizerOptions { Dither = KnownDitherings.Atkinson });
        frameQuantizer = quantizer.CreatePixelSpecificQuantizer<Rgba32>(Configuration.Default);
        Assert.NotNull(frameQuantizer);
        Assert.Equal(KnownDitherings.Atkinson, frameQuantizer.Options.Dither);
        frameQuantizer.Dispose();
    }
}