Other image format

[SMAH1]

Now, I use StbImageSharp to load image and convert by:

using StbImageSharp;

namespace TestUiAOT.Helper;

public static class BmpWriter
{
    public static void ConvertToBmp(string inputPath, string outputBmpPath)
    {
        using var fs = File.OpenRead(inputPath);
        var img = ImageResult.FromStream(fs, ColorComponents.RedGreenBlueAlpha);

        using var bw = new BinaryWriter(File.Create(outputBmpPath));
        WriteBmp32(bw, img.Width, img.Height, img.Data);
    }

    public static byte[] ConvertToBmp(byte[] data)
    {
        var img = ImageResult.FromMemory(data, ColorComponents.RedGreenBlueAlpha);

        using var ms = new MemoryStream();
        using var bw = new BinaryWriter(ms);
        WriteBmp32(bw, img.Width, img.Height, img.Data);
        return ms.ToArray();
    }

    // rgba: length = width*height*4, top-left origin
    private static void WriteBmp32(BinaryWriter bw, int width, int height, byte[] rgba)
    {
        const int fileHeaderSize = 14;
        const int infoHeaderSize = 40;
        int pixelDataSize = width * height * 4;
        int fileSize = fileHeaderSize + infoHeaderSize + pixelDataSize;
        int pixelDataOffset = fileHeaderSize + infoHeaderSize;

        // BITMAPFILEHEADER
        bw.Write((byte)'B');
        bw.Write((byte)'M');
        bw.Write(fileSize);
        bw.Write((short)0);
        bw.Write((short)0);
        bw.Write(pixelDataOffset);

        // BITMAPINFOHEADER
        bw.Write(infoHeaderSize);
        bw.Write(width);
        bw.Write(-height);               // top-down
        bw.Write((short)1);              // planes
        bw.Write((short)32);             // bpp
        bw.Write(0);                     // BI_RGB (no compression)
        bw.Write(pixelDataSize);
        bw.Write(2835);                  // 72 DPI ~= 2835 ppm
        bw.Write(2835);
        bw.Write(0);                     // colors used
        bw.Write(0);                     // important colors

        // Pixel data: BGRA
        for (int i = 0; i < rgba.Length; i += 4)
        {
            byte r = rgba[i + 0];
            byte g = rgba[i + 1];
            byte b = rgba[i + 2];
            byte a = rgba[i + 3];

            bw.Write(b);
            bw.Write(g);
            bw.Write(r);
            bw.Write(a);
        }
    }
}

to convert Gif like:

        var ys = EmbeddedResourceService.LoadEmbedded("Embed.Earth.gif");
        var bmpData = BmpWriter.ConvertToBmp(ys);
        convertedImage = ImageSource.FromBytes(bmpData)!;

I think using a "separate package" (Mention in #31) to load/convert the image is a quick way.
This solution is AOT-Friendly.