Twain and Delphi

Acquire images from scanners, cameras and image capture devices using Delphi. See how to import (and wrap in a component) an image scan control within Delphi.

Technology Without An Interesting Name

TWAIN is a program that lets you scan an image (using a scanner) directly into the application (such as PhotoShop, Photo Paint) where you want to work with the image. Without TWAIN, you would have to close an application that was open, open a special application to receive the image, and then move the image to the application where you wanted to work with it.

Within Delphi

Even though you could use some of the third-party components below, you already might have everything you need to scan an image from a Delphi application. The setup program for Imaging (tool that ships with Windows > 98) installs the Image Scan control (OCX) and the 32-bit TWAIN DLLs. All you have to do is to import this ActiveX control in Delphi and generate a component wrapper:

I'll give you a code snippet on accessing the TImgScan component. Drop one on a form and provide an OnClick event handler for a Button control.

if ImgScan1.ScannerAvailable then
 try 
   ImgScan1.OpenScanner;
   ImgScan1.ScanTo := 2;   
   ImgScan1.Image:='c:\MyPicture.gif';
   ImgScan1.StartScan ;
   Application.ProcessMessages;
 finally  
   ImgScan1.CloseScanner ;
 end;

The rest of the code is yours to explore - there is an imgocxd.hlp help on the Kodak Imaging site.