Load a WebP image
using (Bitmap image = WebPFormat.LoadFromStream(new FileStream("image.webp", FileMode.Open, FileAccess.Read)))
{
image.Save("image.png", ImageFormat.Png);
}
Save a WebP image
using (Image image = Image.FromFile("image.jpg"))
{
Bitmap bitmap = new Bitmap(image);
WebPFormat.SaveToFile("image.webp", bitmap);
}
For more info take a look here webp