annotations/Azaion.Common/Extensions/BitmapExtensions.cs

using System.IO;
using System.Windows.Media;
using System.Windows.Media.Imaging;

namespace Azaion.Common.Extensions;

public static class BitmapExtensions
{
    public static async Task<BitmapImage> OpenImage(this string imagePath)
    {
        await using var stream = File.OpenRead(imagePath);
        return OpenImage(stream);
    }

    public static BitmapImage OpenImage(this Stream stream)
    {
        stream.Seek(0, SeekOrigin.Begin);
        var image = new BitmapImage();
        image.BeginInit();
        image.CacheOption = BitmapCacheOption.OnLoad;
        image.StreamSource = stream;
        image.EndInit();
        image.Freeze();
        return image;
    }

    public static Color CreateTransparent(this Color color, byte transparency) =>
        Color.FromArgb(transparency, color.R, color.G, color.B);

    public static async Task SaveImage(this BitmapSource bitmap, string path, CancellationToken ct = default)
    {
        await using var stream = new FileStream(path, FileMode.Create);
        var encoder = new JpegBitmapEncoder();

        encoder.Frames.Add(BitmapFrame.Create(bitmap));
        encoder.Save(stream);
        await stream.FlushAsync(ct);
    }
}