using System;

using System.Collections;

using System.Drawing;

using System.Drawing.Imaging;

using System.IO;

using System.Net;

using System.Text;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Image Magic Numbers");

        Console.WriteLine("Loaading image from url, save to disk, convert to Image object and show  size ");

        Test1();

    }

      public static void Test1()

        {

              var url = "https://raw.githubusercontent.com/moh-hassan/Images/master/kodim03.png";

            //var url = "http://asd-pc/kodim03.png";

            System.Drawing.Image img = null;

​

            WebClient wc = new WebClient();

            using (MemoryStream stream = new MemoryStream(wc.DownloadData(url)))

            {

                Console.WriteLine("Raw bytes from Url Stream: {0}", stream.Length); //502888

                ImageInfo(stream);

                 //Console.WriteLine("Fill Image object from Url Stream");

              //  img = Image.FromStream(stream);               

            //    

             //   Console.WriteLine("Image.FromStream to byteArray size {0}   ", ImageToByteArray(img).Length );

             //   Byte[] result = (Byte[])new ImageConverter().ConvertTo(img, typeof(byte[]));

             //   Console.WriteLine("ImageConverter().ConvertTo(img,byte[])  size {0}  ", result.Length );

              //  result=null;

             //ImageInfo(img);

                //write filesize on disk

                //what stream to process metadata

                //return GetData(stream);

            }

         GC.Collect();

                DownloadFile(new Uri( url), "temp.png");

                long fileSize = new FileInfo("temp.png").Length;

                Console.WriteLine("file  downloaded and saved to disk, size: {0}",fileSize);

          GC.Collect();

​

        }

     public static void ImageInfo(Image image)

        {

            using (MemoryStream stream = new MemoryStream())

            {

                byte[] imageBytes;

                //image.Save(stream, image.RawFormat);

                image.Save(stream,  ImageFormat.Png);

                imageBytes = new byte[stream.Length];

                imageBytes = stream.ToArray();

                Console.WriteLine("image read from disk to memorystream as RawFormat used for metadata extract, size {0}", imageBytes.Length);

                 Console.WriteLine("Image.FromStream to byteArray size {0}   ", ImageToByteArray(image).Length );

                Byte[] result = (Byte[])new ImageConverter().ConvertTo(image, typeof(byte[]));

                Console.WriteLine("ImageConverter().ConvertTo(img,byte[])  size {0}  ", result.Length );

            }

        }

    public static void ImageInfo(Stream stream2)

        {

          var image = System.Drawing.Image.FromStream(stream2);

           using (MemoryStream stream = new MemoryStream())

            {

                byte[] imageBytes;

                //image.Save(stream, image.RawFormat);

                image.Save(stream,  ImageFormat.Png);

                imageBytes = new byte[stream.Length];

                imageBytes = stream.ToArray();

                Console.WriteLine("stream -> image-> memorystream -> imagbytes,  for metadata extract, size {0}", imageBytes.Length);

            }

        }

      public static void DownloadFile(Uri address, string filePath)

        {

            using (var client = new WebClient())

            using (var stream = client.OpenRead(address))

            using (var file = File.Create(filePath))

            {

                var buffer = new byte[4096];

                int bytesReceived;

                while ((bytesReceived = stream.Read(buffer, 0, buffer.Length)) != 0)

                {

                    file.Write(buffer, 0, bytesReceived);

                }

            }

           var readAllBytes = File.ReadAllBytes("temp.png");

            Console.WriteLine("File.ReadAllBytes from disk , size  :{0}", readAllBytes.Length);

​

        }

      public static byte[] ImageToByteArray( Image image)

        {

            Byte[] result = (Byte[])new ImageConverter().ConvertTo(image, typeof(byte[]));

            return result;

        }

}