Threshold value thru Twain

Discussions about TWAIN & WIA scanning in GdPicture.NET using GdPictureImaging.
Post Reply
Posts: 38
Joined: Tue Dec 02, 2008 1:49 pm

Threshold value thru Twain

Post by charuvas1 » Tue May 11, 2010 2:36 pm


What should be the ideal value for threshold? I want to give a default value to the user. What do you suggest should be the average value incase of threshold?
I understand the value would depend upon the document being scanned. However just a rough estimate would help.

Is there a function for autothreshold in Twain? If I dont give any value for threshold, I could just call the autothreshold function.
What does AutoBrightness do in Twain scanning?


User avatar
Site Admin
Posts: 5812
Joined: Tue Oct 17, 2006 10:48 pm
Location: France

Re: Threshold value thru Twain

Post by Loïc » Tue May 11, 2010 2:52 pm


As you understood, there is no ideal value, it depends on input document & scanner lamps.
Usually the default value is 127.

Kind regards,


Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest