This post shows an example of scanning an image with C#. First of all start Visual Studio and create a new console application.

In this example I make use of the standard WIA scanning functionality in Windows 7. Reference the WIA dll in your new project. The dll can be found in the folder “c:\windows\system32\wiaaut.dll”.

The code below scans an image (A4 size) at the default 300 DPI and stores it as an uncompressed TIFF image.

namespace Scanner
{
   using System;
   sing System.Runtime.InteropServices;

   class Program
   {
      const string WIA_DEVICE_PROPERTY_PAGES_ID = "3096";
      const string WIA_DEVICE_PROPERTY_PAGES_ID = "3096";
      const string WIA_HORIZONTAL_SCAN_RESOLUTION_DPI = "6147";
      const string WIA_VERTICAL_SCAN_RESOLUTION_DPI = "6148";
      const string WIA_HORIZONTAL_SCAN_START_PIXEL = "6149";
      const string WIA_VERTICAL_SCAN_START_PIXEL = "6150";
      const string WIA_HORIZONTAL_SCAN_SIZE_PIXELS = "6151";
      const string WIA_VERTICAL_SCAN_SIZE_PIXELS = "6152";
      const string WIA_SCAN_BRIGHTNESS_PERCENTS = "6154";
      const string WIA_SCAN_CONTRAST_PERCENTS = "6155";
      const int widthA4at300dpi = 2480;
      const int heightA4at300dpi = 3508;

      static void Main(string[] args)
      {
         WIA.CommonDialogClass commonDialogClass = new WIA.CommonDialogClass();
         WIA.Device scannerDevice = null;

         try
         {
             scannerDevice = 
                commonDialogClass.ShowSelectDevice(
                   WIA.WiaDeviceType.ScannerDeviceType,
                   false, 
                   false);

             SetWIAProperty(scannerDevice.Properties, WIA_DEVICE_PROPERTY_PAGES_ID, 1);
             WIA.Item scannnerItem = scannerDevice.Items[1];

             SetA4(scannnerItem.Properties, 300);

             WIA.ImageFile scanResult = 
                commonDialogClass.ShowTransfer(
                   scannnerItem, 
                   WIA.FormatID.wiaFormatTIFF, 
                   false);

             scanResult.SaveFile("output.tiff");
         }
         catch (COMException ex)
         {
            if ((uint)ex.ErrorCode == 0x80210015)
            {
               Console.WriteLine("No scanner attached");
            }
            else
            {
               Console.WriteLine("Unknown error: {0}", (uint)ex.ErrorCode);
            }
         }
      }

      private static void SetA4(WIA.IProperties properties, int dpi)
      {
            int width = (int)((widthA4at300dpi / 300.0) * dpi);
            int height = (int)((heightA4at300dpi / 300.0) * dpi);

            SetWIAProperty(properties, WIA_HORIZONTAL_SCAN_RESOLUTION_DPI, dpi);
            SetWIAProperty(properties, WIA_VERTICAL_SCAN_RESOLUTION_DPI, dpi);
            SetWIAProperty(properties, WIA_HORIZONTAL_SCAN_START_PIXEL, 0);
            SetWIAProperty(properties, WIA_VERTICAL_SCAN_START_PIXEL, 0);
            SetWIAProperty(properties, WIA_HORIZONTAL_SCAN_SIZE_PIXELS, width);
            SetWIAProperty(properties, WIA_VERTICAL_SCAN_SIZE_PIXELS, height);
       }

       private static void SetWIAProperty(WIA.IProperties properties, 
              object propName, object propValue)
       {
          WIA.Property prop = properties.get_Item(ref propName);
          prop.set_Value(ref propValue);
       }
    }
}