Re: Scanning mixed sizes / image auto-sizing issue

Hi,

Users of my product often have to scan images of documents with mixed sizes - let's say a document can have US Letter size sheets combined with US Legal size sheets. Currently, they have to specify the size they are going to scan, and so they have to break up scanning of a document into scanning of sheets of the same size.

Is there a TWAIN capability that I can set to have the scanner define / recognize the size automatically? Or is there a way to use the Doc Imaging toolkit to do the sizing, e.g. scan at the maximum size (US Legal) and if there's a block of white space after Letter-size dimensions, cut the the legal-size image down to letter-size?

I checked the Twain 1.9 specs and also this forum for any answers. The only thing I found is AutoTrim call on an image, but I couldn't locate that method or property in the LT help file. AutoTrim may not be the right answer in my case anyway, because I don't want to trim the scanned sheet all the way down to it's bare content. I just want to trim letter-sized page scanned as legal-sized image down to letter-sized image.

Thanks.

There are no official TWAIN capabilities that I know of that can detect the size of the paper.  Some scanners (especially flatbeds) might have this as a custom capability.  You can use LEADTOOLS' Get and SetCapability methods to negotiate any TWAIN capabilities including custom ones specific to that scanner.  If your scanner supports it and you want to use that capability, you will need to contact the vendor of the scanner or consult it's documentation to see what the capability information is so you can use Get/SetCapability.

As for trimming a letter size paper scanned as legal, AutoTrim should work well as long as the background is a different color than the rest.  Ideally your image would be black and white, and there would be a black border of the image that is smaller than legal, but it can also work with color images.

Thank you. That answers my question.