Dynamsoft TWAIN Products

Hello, we are a company considering buy of Dynamic .NET TWAIN. Our aim is to use it for scanning in our WPF application. Unfortunbately, we have problems with scanning. It seems that there is problem in responding to TWAIN messages in message processing loop inside Dynamic .NET TWAIN. After calling AcquireImage() the scanner app dialog shows up, then clicking on "Scan" another dialog shows up with label "Scanning...". This is, when the scanner should start scanning, but it doesn't. So my question is, is there any way to use Dynamic .net TWAIN inside WPF applications? We would be very happy for any advices regarding this problem. There is no problem when using your WinForms samples. Please help us.
Sincerely, Peter Javorsky

Hi Peter,

Dynamic .NET TWAIN can be used in WPF applications.

Did you get any error message when scanning? If so, please let us know so that we can look into this issue more closely. You can use ErrorString property to get the error message:
http://www.dynamsoft.com/help/TWAIN/.Ne ... String.htm

If you like, you can contact us via LiveHelp to have a GoToMeeting session. With GoToMeeting, you can share your desktop and give us controls of your mouse and keyboard when necessary. Our LiveHelp can be found at:
http://www.dynamsoft.com/support/livehelp.aspx

Thanks.

Hi Catherine, thanks for your reply.
This is odd, but I just started reading ErrorString and now the scanning works. Previously, we tested it on 2 different scanners and scanning didn't start. Thank you for your help.

Thanks for the update. Glad to hear that it is working now.

No problem Catherine. I figured out that it works only when build mode is set to "Release". When I set it to "Debug", situation is the same and the scanning won't start. First time it worked with "Debug" mode only because vshost process crashed. After that, after restarting Visual Studio it stopped working again. Now it works with "Release" set, as I mentioned.

Hi Peter,

We tested WPF applications embedding Dynamic .NET TWAIN. It works fine under the Debug mode. If you like, you can contact us via LiveHelp to have a GoToMeeting session, so that we can check your application together to find out why the scanning does not work under the Debug mode.
http://www.dynamsoft.com/support/livehelp.aspx

Hi, we have another problem. We want in some cases stop scanning in method OnPostTransfer(), so we're calling CancelAllPendingTransfers(), but on some scanners (Canon imageFORMULA DR-2510C, and Panasonic KV S1045) they feed one extra page, and then they stop. We need that the scanner stops immediately. Can you help us please?

Hi tekk,

To better pinpoint the cause of the problem, shall we have a GoToMeeting session? If it is convenient for you, please contact us via LiveHelp:
http://www.dynamsoft.com/support/livehelp.aspx

Thanks.

I can tell my colleague to have a GoToMeeting session with you. What exact time do you prefer? But he doesn't have the source code. He figured out, that on Canon scanner, to stop the scanner properly, function "Rapid Recovery" must be turned off, but it's turned on by default. On Panasonic scanner it's "Length Control", when turned on it feeds one extra page.

Hi tekk,

It seems that the cause of the problem is the driver of the scanner. If this is the case, I recommend you turn off "Rapid Recovery" or "Length Control". Or you can consult the manufacturer of the scanners to see if they have any suggestions.

To have a GoToMeeting session, you can contact our support team via LiveHelp during 9:00 AM ~ 6:00 PM PST.
http://www.dynamsoft.com/support/livehelp.aspx

Thanks.

Hi, we have problems using mentioned Canon scanner, image looks like this:
http://img96.imageshack.us/img96/172/5520101.png
This is how we obtain image for our purposes:

Do you have any idea what can cause this?

Hi tekk,

I cannot view the image through the link you provided.

To better pinpoint the cause of the problem, you can send your original and result images, along with your TWAIN-related code, to nettwain@dynamsoft.com. Our support team will check it for you.

Thanks.

Try these links:

Expected:
http://www.javorsky.sk/TAP2/expected.png

Result:
http://www.javorsky.sk/TAP2/result.png

Ignore the colour marks on the form, it's made by our app.
Outside our app, scanning works fine.
It looks like DotNetTwain thinks that it's Letter format, but it's A4.

Hi tekk,

To better pinpoint the cause of the problem, would you please be more specific about the problem you are experiencing? Are you referring to the page size issue, or both the page size and image quality issues? I cannot tell the words in result.png. I am not sure if it is made by your app or the result of scanning.

For the page size issue, you can use PageSize property to set the page size. For more information, please refer to:
http://www.dynamsoft.com/help/TWAIN/.Ne ... geSize.htm

Also, shall we have a GoToMeeting session during 6:30 PM ~ 7:30 PM PST so that I can look into this issue more closely?
http://www.dynamsoft.com/support/livehelp.aspx

Thanks.

Sorry, but I don't have the scanner. Only testers has scanners, but they don't have the code. So it's impossible to solve it with GoToMeeting.