DTWAIN_AcquireFile+ DTWAIN_USESOURCEMODE with callbacks to inspect most recent image?

[dmccallie]

Is it possible to use DTWAIN_AcquireFile() and the DTWAIN_USESOURCEMODE mode (the scanner does the file saving) along with a callback function that would allow the application to inspect the image using the trigger DTWAIN_TN_QUERYPAGEDISCARD and DTWAIN_GetCurrentAcquiredImage()?

Also, in the USESOURCEMODE could returning 0 to the message DTWAIN_TN_PAGECONTINUE be used to stop subsequent scanning?

Thanks!

[dynarithmic]

Unfortunately the TWAIN specification for DTWAIN_USESOURCEMODE does not allow images to be created, only files, so DTWAIN_GetCurrentAcquiredImage isn't utilized at all. The only notifications you will get with DTWAIN_USESOURCEMODE would be DTWAIN_TN_FILESAVEOK, DTWAIN_TN_FILEPAGESAVEOK and DTWAIN_TN_FILESAVEERROR.

So you probably have to devise a way to have the file saved (you can't intercept this), handle one or more of the mentioned notifications, and then have a (probably third-party) viewer to view the file to the user. Then you would save or delete the file depending on the user's choice.

I haven't tried DTWAIN_TN_PAGECONTINUE and DTWAIN_USESOURCEMODE together, but theoretically it should work, provided that your scanner driver has multipage support (most likely DTWAIN_FF_TIFFMULTI).

[dmccallie]

When the callback gets DTWAIN_TN_FILESAVEOK is there any way inside the callback to find the filename of the file just saved?

[dynarithmic]

You can use the DTWAIN_GetSaveFileName function.

[dmccallie]

Thanks, I will give it a try.