Home › Forums › TWAIN Classic › capability to find if document feeder is loaded
- This topic has 4 replies, 4 voices, and was last updated 10 years, 1 month ago by Kaij.
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Greetings!
We have an application which is used to scan documents from TWAIN supported scanner. We are using TWAIN driver WIA driver
When scanned using the application, we found that “TWRC_CANCEL” is returned after all pages are acquired from document feeder, though the scanning process is not cancelled.We are using third party library API’s to acquire images from scanner. The third party acquire API retuned “TWRC_CANCEL” error.
“TWRC_CANCEL” error is received even when we used “TWACKER” application to scan from the same scanner.
To identify if the user has actually cancelled the scanning process, we need to find if document feeder has any loaded pages(remaining pages may be there) . To do that we used the capability “CAP_FEEDERLOADED” .
But our scanner is always returning TRUE even though paper is not available in the document feeder.Other Information:
We installed TWAIN driver by using the below steps.
1. Executed the installation steps of TWAIN driver provided by scanner vendor.
2. Added this device from “Scanners and Cameras” in control panel.
Now the device is listed in the application with the name as WIA-XX-TWAIN-XX…
The error is retunred in Windows 7 and Windows 8 only.Please let us know if we can use any other capability to find if the document feeder is loaded.
Thank you.
Hi sharp1257.
It’s OK to mention the actual name and model of your scanner, leaving it out just makes things harder, since many TWAIN problems are at least a little bit device-specific.
There definitely are a few scanners that return TWRC_CANCEL (incorrectly) when the scan-job finishes. I’m thinking particularly of Brother MFC’s…
If I remember correctly, this is also a problem when using the WIA drivers through TWAIN, I even have a vague memory that it might be more of a problem when going through WIA.And I’m not sure how well feederloaded works through WIA either… Hmm. I just opened my AV220C2 through “WIA-AV220C2”, and it returns CAP_FEEDERLOADED=TRUE, with the feeder totally empty. 🙄 Not a good sign.
I don’t think you will get best results using the device “WIA-XX-TWAIN-XX”
1. Executed the installation steps of TWAIN driver provided by scanner vendor.
2. Added this device from “Scanners and Cameras” in control panel.
Now the device is listed in the application with the name as WIA-XX-TWAIN-XX…
The error is retunred in Windows 7 and Windows 8 only.Something is wrong here. If you are using a device with a name that starts with “WIA-” then you aren’t using a native TWAIN driver, you are going through WIA.
And you don’t need to do anything in the Scanners & Cameras control panel, in order to use a TWAIN driver.Suggestion: Run a 3rd party TWAIN application like Twacker (from the TWAIN Working Group’s toolkit), or Irfanview (from http://www.irfanview.com).
Look at the list of TWAIN devices in that application. If your scanner does not appear without a WIA-prefix, then you don’t yet have a working TWAIN driver. Troubleshoot, perhaps with help from the vendor.Once your scanner appears in the TWAIN device list without “WIA-” in front of it, switch your application to use that. Then you can query the TWAIN value ‘CAP_FEEDERLOADED’ to see if the feeder is loaded. Maybe when you switch to the native TWAIN driver it won’t return bogus TWRC_CANCEL, so you won’t need to work around it. No promises though 8)
I’m involved in an application which is used to scan documents from TWAIN supported scanner. For my case, the scanner dialog closes after transferring each scanned image. To scan the next page requires re-starting the scanner, beginning with a whole new preview and re-entering all my scan settings. Can anyone help me to scan multiple images in my TWAIN scanning application?
Hi Susanna, thanks for spamming our forum.
I bet this really helps the reputation of RasterEdge with imaging professionals.
Of course, we are talking about a company that doesn’t have a phone number 8)- AuthorPosts