Increasing the color depth of captured images, Reducing the color depth of captured images – Epiphan VGA2USB Pro User Manual
Page 75
12. Windows video capture application
Recording, display, KVM and sharing options
User Guide
Page 75
• You have special requirements for a color depth that is
different from the color depth produced by the video source.
Set the display format to the color depth that you require.
Epiphan Frame Grabbers capture images at the color depth of the
video source up to the maximum color depth supported by the
Frame Grabber. The maximum color depth supported by the
VGA2USB Frame Grabber is 16 bits per pixel (bpp). The
maximum color depth supported by all other Epiphan Frame
Grabbers is 24 bpp.
Increasing the color depth of captured images
The VGA2USB Frame Grabber captures images at 16 bpp. If
16 bpp is supported by the codec or image file format that you are
using, you should also set the display format to RGB 16 bits per
pixel. Setting the display format to RGB 24 bits per pixel requires
the Frame Grabber device driver to convert the image format
from RGB 16 to RGB 24. This results in extra CPU and memory
usage and larger image or video files but the image quality (or
amount of information) is still the same as in the original RGB 16
images that came from the Frame Grabber.
However, in most cases even with a VGA2USB Frame Grabber
you would usually operate at 24 bpp because this color depth is
required by most video codecs and also for web broadcasting.
In most cases image capture and recording performance should
be acceptable if the video capture workstation meets or exceeds
the hardware requirements described in
and if there are not a lot of concurrent
demands on this PC.
Reducing the color depth of captured images
All DVI2USB Frame Grabbers and the VGA2USB LR/HR/PRO
Frame Grabbers can capture images at RGB 24 bpp. If your video
source is operating at RGB 24 bpp and you set the display format
lower than RGB 24 bpp, you are reducing the quality of the
captured image. You are also causing the Epiphan USB device
driver to consume extra CPU and memory resources to convert
the images to the reduced color depth.