Enable Multi-Page Scanning

The MaximumImages property is negotiated with the TWAIN Data Source during initialization (OpenSession) and should be set prior to invoking the OpenSession method.

This property is only used when the OpenSession method is invoked. To set the transfer count after calling OpenSession, use the CAP_XFERCOUNT capability.

A value of –1 indicates the application is willing to transfer multiple images.
A value of 1 indicates the application wishes to transfer only one image per session.

The Data Source should be set before opening a TWAIN session (TwainDevice.OpenSession).