WPF image speed benchmark.

Program.cs

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System.IO;
using System.Windows.Media.Imaging;

BenchmarkRunner.Run<WpfBitmapSourceBenchmark>();

public class WpfBitmapSourceBenchmark
{
    [Params(@"img100x100.bmp", @"img1000x1000.bmp")]
    public string? FilePath { get; set; }

    private const BitmapCreateOptions CreateOptions = BitmapCreateOptions.IgnoreColorProfile;
    private const BitmapCacheOption CacheOption = BitmapCacheOption.OnLoad;

    private FileStream? _stream;

    [GlobalSetup]
    public void GlobalSetup()
    {
        _stream = File.OpenRead(FilePath!);
    }

    [GlobalCleanup]
    public void GlobalCleanup()
    {
        _stream?.Dispose();
    }

    [Benchmark]
    public BitmapImage BitmapImage_FromStream()
    {
        BitmapImage image = new();
        image.BeginInit();
        image.CreateOptions = CreateOptions;
        image.CacheOption = CacheOption;
        image.StreamSource = _stream;
        image.EndInit();
        image.Freeze();
        return image;
    }

    [Benchmark]
    public BitmapFrame BitmapFrame_FromStream()
    {
        BitmapFrame image = BitmapFrame.Create(_stream, CreateOptions, CacheOption);
        image.Freeze();
        return image;
    }

    [Benchmark]
    public BitmapSource BitmapDecoder_FromStream()
    {
        BitmapDecoder decorder = BitmapDecoder.Create(_stream, CreateOptions, CacheOption);
        BitmapSource image = decorder.Frames[0];
        image.Freeze();
        return image;
    }
}

result.md

BenchmarkDotNet v0.13.12, Windows 11 (10.0.22621.3155/22H2/2022Update/SunValley2) AMD Ryzen 7 PRO 4750GE with Radeon Graphics, 1 CPU, 16 logical and 8 physical cores .NET SDK 8.0.200 [Host] : .NET 8.0.2 (8.0.224.6711), X64 RyuJIT AVX2 [AttachedDebugger] DefaultJob : .NET 8.0.2 (8.0.224.6711), X64 RyuJIT AVX2

Method	FilePath	Mean	Error	StdDev
BitmapImage_FromStream	img1000x1000.bmp	4,376.1 us	10.75 us	10.06 us
BitmapFrame_FromStream	img1000x1000.bmp	4,383.9 us	11.66 us	9.74 us
BitmapDecoder_FromStream	img1000x1000.bmp	4,404.9 us	38.44 us	35.96 us
BitmapImage_FromStream	img100x100.bmp	322.5 us	1.17 us	1.04 us
BitmapFrame_FromStream	img100x100.bmp	315.8 us	1.07 us	0.95 us
BitmapDecoder_FromStream	img100x100.bmp	316.2 us	0.84 us	0.75 us