ImageGear for C and C++ on Windows v19.10 - Updated
Set the TWAIN Image Acquisition Mode
User Guide > How to Work with... > Common Operations > Scanning > TWAIN Scanning > Set the TWAIN Image Acquisition Mode

There are three acquisition modes in TWAIN:

Remember that not all of the TWAIN-supported transfer syntax modes are supported by all Data Sources. If you try to use an acquisition mode that your device does not support, you will receive an error message.

Tell ImageGear the transfer mode to use with the function IG_TWAIN_cap_set().

By default, if no call is made to set transfer mode, ImageGear will use the mode set in Data Source.