Thursday, 31 March 2016

What is WIA & TWAIN

Reports On (TWAIN & WIA)

Similarities: 
  • As long as a driver exists, both are able to acquire images from devices such as a scanner or camera.  For devices like cameras, sometimes the driver is actually WIA but we can access it via the "TWAIN compatibility layer". 
  • Acquire images with a dialog. 
  • Programmatically set properties of the device and acquire the images programmatically without showing a dialog 
  •  Not all capabilities are supported by each device, so you can query the device for the ones that it does support. 





Functions of the TWAIN and WIA scanners
Functions
TWAIN
WIA
1. Scan
Scan from the exposure glass
Yes
Yes
Continuous scanning from the ADF
Yes
Yes
ADF Read-ahead
Yes
Yes 
Specify the number of originals to be scanned from the ADF
Yes 
Yes 
Preview
Yes
Yes 
Scan using an application that do not have user interface
Yes
Yes
2. Setting
Driver selection
Yes
Yes
Initial Settings
  • Unit of Measure: (mm, inch, pixel)
Yes
No
  • Compression
Yes
No
Deskew
Yes
No
Start from Scanner
Yes
No
Save/Delete Mode
Yes
No
Specify original size
  • When scanning from the exposure glass
Yes
Yes 
  • When scanning from the ADF
Yes
Yes
Orig.Orientn.
Yes
Yes 
Orientation:
Yes
Yes 
Scan Settings:
  • 1 Sided
Yes
Yes
  • 2 Sided
Yes
Yes
  • 2 Sided (Top to Top, Top to Bottom)
Yes
No
Resolution
Yes
Yes
Brightness:
Yes
Yes
Contrast:
Yes
Yes
Threshold:
Yes
Yes 
Col. /Grad.:
  • Binary
Yes
Yes
  • Grey Scale
Yes
Yes
  • 8 Colors
Yes
No
  • 16770K colors (Full color)
Yes
Yes
Gam-Curve:
Yes
No
Eras.Bgrnd:
Yes
No
Advanced
  • Filter (Filter, Dropout Col.)
Yes
No
  • Color Matching (ICM:, Inversion)
Yes
No
Save/Delete Scanning Area
Yes
No
Specify original size (specify scan area manually)
Yes
No
Comb./Series
Yes
No
Endorser
Yes
No
3. Properties
General
  • Diagnosis (Scan test)
No
Yes
Authenticate
  • User Code:
Yes
Yes
  • General User Authentication
Yes
Yes
Network Connection
  • Settings for using a specific scanner
Yes
Yes
  • SNMP V3 Auth.information
Yes
Yes
Driver version display
Yes
Yes
  

Differences:-

see the difference between WIA and TWAIN

SlN.
TWAIN
WIA
1
Twain uses a dialog created by the device manufacturer. TWAIN dialog will provide more options and advanced control over the device

WIA uses a common dialog for all devices that means it is does not provide more option and advance control over the device.

2
TWAIN is supported on all versions of Windows, on Mac OS (8, 9, and X). TWAIN 2.0 early for Linux, Unix, and 64-bit Windows.
WIA only works on windows ME, XP and Vista and above.
3
TWAIN API supports both WIA-based and Twain based scanners.
WIA applications are guaranteed to be base-level compatible with all WIA-based scanners.
4
TWAIN will support Windows, Linux and Mac OS X using TWAIN drivers.
WIA will support Windows applications such Windows Fax and Scan and Paint without the need for any additional software.
5
TWAIN has three transfer modes (Native, Memory, File).
WIA has only 2 transfer modes (Memory and File). 
6
Most TWAIN sources save the settings of a previous scan.
WIA has limited functionality and does not.
7
TWAIN allows you to use custom capabilities that the device manufacturer has created even though they don't exist in the TWAIN specifications.
 WIA does not allow you to custom capabilities that device manufacturer has created or provided.
8
TWAIN supports options for each page when scanning in duplex mode.
WIA uses the same setting for both sides when we are scanning in duplex mode.  
9
TWAIN API is designed for use by C/C++ programmers. Familiarity with the Windows GUI and Component Object Model (COM) interfaces is required.
The WIA API is designed for use by C/C++ programmers. Familiarity with the Windows GUI and Component Object Model (COM) interfaces is required.
10
TWAIN provide an open, multi-platform solution to interconnect the needs of raster input devices with Application software.

Network connected imaging devices that support Web Services for Devices (WSD) protocol can also be used from WIA-compliant imaging applications on Windows Vista and Windows 7 out of the box via a WSD-WIA class driver that shipped as part of Windows Vista. 
11
TWAIN is not concerned with the device layer at all. The Source hides the device layer from the application. The Source provides the translation from TWAIN operations and interactions with
the Source’s user interface into the equivalent commands for the device driver.

The class driver converts WIA calls to WSD calls and vice versa and makes already existing WIA applications work with WSD based scanners without any additional driver.
12
Most of the companies supports TWAIN.
List Of Scanner which support WIA-



List Of Scanner which support WIA-