using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.IO;

public class ImageClass
{
    
    private static byte[] ResizeImageFile(byte[] imageFile, int targetSize)
    {
        using (System.Drawing.Image oldImage = System.Drawing.Image.FromStream(new MemoryStream(imageFile)))
        {
            Size newSize = CalculateDimensions(oldImage.Size, targetSize);//User defined function to calculate image dimensions
            using (Bitmap newImage = new Bitmap(newSize.Width, newSize.Height, PixelFormat.Format24bppRgb))
            {
                using (Graphics canvas = Graphics.FromImage(newImage))
                {
                    canvas.SmoothingMode = SmoothingMode.AntiAlias;//set rendering quality of canvas
                    canvas.InterpolationMode = InterpolationMode.HighQualityBicubic;//set interpolation mode to HighQualityBiubic
                    canvas.PixelOffsetMode = PixelOffsetMode.HighQuality;
                    canvas.DrawImage(oldImage, new Rectangle(new Point(0, 0), newSize));//drow image in canvas with new size and with specific starting location
                    MemoryStream m = new MemoryStream();
                    newImage.Save(m, ImageFormat.Jpeg);//define image formate in which it is to be shown
                    return m.GetBuffer();//return image as byte array
                }
            }
        }
    }

    private static Size CalculateDimensions(Size oldSize, int targetSize)
    {
        Size newSize = new Size();

        //change the size according to the widh and height
        if (oldSize.Height > oldSize.Width)
        {
            newSize.Width = (int)(oldSize.Width * ((float)targetSize / (float)oldSize.Height));
            newSize.Height = targetSize;
        }
        else
        {
            newSize.Width = targetSize;
            newSize.Height = (int)(oldSize.Height * ((float)targetSize / (float)oldSize.Width));
        }
        return newSize;
    }
}