Epiphan VGA2USB Pro - Manual (Page 34)

11. About Epiphan frame grabbing technology The video capture workstation
Page 34 Epiphan Frame Grabber
notable difference is that each platform includes different image
processing application programming interfaces (APIs):
• On Windows 2000, XP, and Vista the Epiphan USB device
driver and video capture application is compatible with the
Microsoft DirectShow API.
• On Mac OS X the Epiphan USB device driver and video
capture application is compatible with the Apple QuickTime
API.
• On Linux the Epiphan USB device driver and video capture
application is compatible with the Video4Linux V4L API.
The following sections describe the video capture workstation
software components and APIs on each supported video capture
application platform.
•
“Windows video capture application software” on page 35
• “Mac OS X video capture workstation software” on page 40
• “Linux video capture workstation software” on page 42
About kernel mode and user mode
Some video capture workstation software components operate in
kernel mode and some in user mode. Kernel mode programs are
usually always running in the background and are usually not
started and stopped by users. Kernel mode programs are usually
configured from a central location such as the Windows control
panel. Most software that communicates directly with hardware
components operate in kernel mode. On all operating systems the
Epiphan USB device driver is a kernel mode application.
User mode programs are programs that users run to perform a
task such as word processing, drawing graphics, or recording
captured images. Users start, stop, use and configure user mode
programs. User mode programs do not usually communicate
directly with hardware components. They communicate with
kernel mode programs and it is the kernel mode programs that
communicate with the hardware components. The Epiphan video
capture application is a user mode program.