From: "Brent"
| On Sat, 13 Feb 2010 07:59:11 -0500, David H. Lipman wrote:
For this scenario a TWAIN capable program that will scan and create a PDF.
| David,
| I don't understand the TWAIN part. I tried all the suggested programs but
| none could find the printer.
| Which side do I need the TWAIN software?
| On the PC side where I run the application to talk to the printer?
Brent:
All scanners have two seperate but merging softwares that allow them to be used by a
computer.
1. Hardware drivers.
2. TWAIN GUI middleware.
Once a given scanner has its hardware drivers installed, the Operating System knows how to
communucate with the hardware.
Once the TWAIN GUI middleware is installed any program that is TWAIN complaint will be
able to use the scanner.
For example I have a Canon colour flatbed and a HP 100 laser scanner attachment.
Now the Cannon has both #1 and #2 in two separate installers and connects via USB v2.0.
It shows up in Device Manager under "Imaging Devices" (WinXP).
The HP Lasetjet 1100 has an attachment that plugs in the front of the laser printer. The
Laserprinter connects to PC via parallel port. However in my case, it is connected to an
external HP JetDirect print server. Here #1 and #2 is included into one installer for its
own application, "Laserjet Document Assiastant" and it runs in the background and you tell
it if the Printer+Scanner is connected via parallel port or over then LAN.
Take a program like XnView. It is a TWAIN compliant graphics application. Thus *any*
TWAIN complaint scanner who had their software installed correctly (Part #1 and #2) then
one can choose which is the default scanner. (Note the OS can only define one device as
"default scanner" at a time and thus once set, that chosen scann will the dafault for ALL
TWAIN compliant software under that OS).
One the default scanner is chosen you can actually initiate a scan and hold the object in
memory. Now its dependent upon what TWAIN compliant application does as its objective.
If it is XnView its is considered a graphic and thus you can now save it in any of the
standard formats like; .JPG, .PNG, .TIFF, .DCX., .PVX, etc.... Add PDFCreator from
SourceForge into the picture and you can now create a PDF from the scanned object.
Lets use another scnerio:
Lets us say you have Open Office (OO). OO is TWAIN comliant and can natively create PDFs.
Thus many of the modules will be able to scan into its respective Office application such
as its Word Processor and from there perform the scan and subsequently create a PDF.
No matter what application that one uses when you have chosen the deafult scanner, you
will use that particular scanner's TWAIN GUI interface. It will allow you resize, scan
portion, allow colour/B&W/Grey Scale and indicate at what Dot Per Inch (DPI) level.
So to sum it all up, the TWAIN is a standard for any TWAIN compliant application to use
and TWAIN compliant scanner. The TWAIN GUI is the middlware provided by the scanner
manufacturer and provides an interface to the device. With it you tell the scanner what
to sca, how to scan and in what format. Once scanned it is delivered to the requesting
application. That requesting application (through its TWAIN compliance) then can use the
scanned image for whatever pupose it needs.
http://en.wikipedia.org/wiki/TWAIN
--
Dave
http://www.claymania.com/removal-trojan-adware.html
Multi-AV -
http://www.pctipp.ch/downloads/dl/35905.asp