https://learn.microsoft.com/en-us/dotnet/api/system.windows.media.imaging.gifbitmapencoder?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-9.0
GifBitmapEncoder Class (System.Windows.Media.Imaging) | Microsoft Learn
Defines an encoder that is used to encode Graphics Interchange Format (GIF) images.
class systemwindows mediaimagingmicrosoftlearn