calculate the aspect ratio of image

CalculateAspectRatio.cs

public Size CalculateAspectRation(int desiredWidth, int desiredHeight, Image image){

  var widthScale = (double)desiredWidth / image.Width;
  var heightScale = (double)desiredHeight / image.Height;
  var scale = widthScale < heightScale ? widthScale : heightScale;

  return new Size
  {
      Width = (int)(scale * image.Width),
      Height = (int)(scale * image.Height)
  };
  
}

CalculateAspectRatio.js

function CalculateAspectRatio(desiredWidth, desiredHeight, width, height) {
    var widthScale = parseFloat(desiredWidth / width);
    var heightScale = parseFloat(desiredHeight / height);
    var scale = widthScale < heightScale ? widthScale : heightScale;

    return {
        Width: parseInt(scale * width),
        Height: parseInt(scale * height)
    };
}