using System; using System.Globalization; using System.Windows.Data; namespace NativeFilterDemo { public class AspectRatioValueConverter : IValueConverter { public object Convert(object value, Type targetType, object parameter, CultureInfo culture) { if (value is double) { double length = (double)value; return length * 3 / 4; //Fixed 4:3 aspect ratio } throw new NotSupportedException(); } public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) { throw new NotSupportedException(); } } }