ImageSharp/tests/ImageSharp.Benchmarks/Codecs/EncodeGif.cs

// Copyright (c) Six Labors and contributors.
// Licensed under the Apache License, Version 2.0.

using System.Drawing.Imaging;
using System.IO;
using BenchmarkDotNet.Attributes;
using SixLabors.ImageSharp.Formats.Gif;
using SixLabors.ImageSharp.PixelFormats;
using SixLabors.ImageSharp.Processing;
using SixLabors.ImageSharp.Processing.Processors.Quantization;
using SixLabors.ImageSharp.Tests;
using SDImage = System.Drawing.Image;

namespace SixLabors.ImageSharp.Benchmarks.Codecs
{
    [Config(typeof(Config.ShortClr))]
    public class EncodeGif : BenchmarkBase
    {
        // System.Drawing needs this.
        private Stream bmpStream;
        private SDImage bmpDrawing;
        private Image<Rgba32> bmpCore;

        [GlobalSetup]
        public void ReadImages()
        {
            if (this.bmpStream == null)
            {
                this.bmpStream = File.OpenRead(Path.Combine(TestEnvironment.InputImagesDirectoryFullPath, TestImages.Bmp.Car));
                this.bmpCore = Image.Load<Rgba32>(this.bmpStream);
                this.bmpStream.Position = 0;
                this.bmpDrawing = SDImage.FromStream(this.bmpStream);
            }
        }

        [GlobalCleanup]
        public void Cleanup()
        {
            this.bmpStream.Dispose();
            this.bmpCore.Dispose();
            this.bmpDrawing.Dispose();
        }

        [Benchmark(Baseline = true, Description = "System.Drawing Gif")]
        public void GifSystemDrawing()
        {
            using (var memoryStream = new MemoryStream())
            {
                this.bmpDrawing.Save(memoryStream, ImageFormat.Gif);
            }
        }

        [Benchmark(Description = "ImageSharp Gif")]
        public void GifCore()
        {
            // Try to get as close to System.Drawing's output as possible
            var options = new GifEncoder
            {
                Quantizer = new WebSafePaletteQuantizer(new QuantizerOptions { Dither = KnownDitherings.Bayer4x4 })
            };

            using (var memoryStream = new MemoryStream())
            {
                this.bmpCore.SaveAsGif(memoryStream, options);
            }
        }
    }
}