Doc # INS-16001
Issue Date: 07/20/2016
Revision: 2.1.0.0
Page 26 of 27
The TWAIN interface will attach itself to the first Credential Cam Pro Plus camera it finds connected to the
computer. For best operation, run the TWAIN Interface on a system that has only one Credential Cam Pro
Plus camera installed.
Any application that supports a TWAIN Data Source as a capture device can access the camera. The
camera's image will appear as shown below:
7.1.
Zoom Feature
The optical zoom function can be used to frame the subject within the field of view (FOV). The subject
may be of differing height, distance, or position within the FOV, and the optical zoom provides a means
of sizing and positioning the frame to provide an image of the correct proportions.
With no optical zoom capability within the camera, the user must resort to alternative means of framing
the image to the size and proportions required.
One option would be to provide real time digital zoom, but doing this within the live video stream is
problematic, as it would result in reduced frame rates and could compromise video quality.
An alternative approach is to provide a means of defining the size and position of the captured image
within the streaming video. This is somewhat analogous to aiming and zooming the camera with the
optical zoom.
7.1.
Mode of Operation
7.1.1.
Preview Mode
The streaming video is shown in 640 x 480 resolution.
The operator would view the subject in preview mode and then drag a box over the image to define the
capture area. The box can be of any size and location within the image.
