EnumToImageConverter.cs

public class EnumToImageConverter : IValueConverter
{
    public string SubFolder { get; set; }

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value is Enum && targetType == typeof(ImageSource))
        {
            var enumType = value.GetType();
            var format = String.IsNullOrEmpty(SubFolder) ? "/Assets/{0}/{2}.png" : "/Assets/{0}/{1}/{2}.png";
            var path = String.Format(format, enumType.Name, SubFolder, Enum.GetName(enumType, value));
            var uri = new Uri(path, UriKind.Relative);
            return new BitmapImage(uri);
        }

        return value;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}