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StillColor
This appendix describes the different methods you can use to acquire a
color image using the IMAQ PCI/PXI-1408 and National Instruments
StillColor technology, explains basic color theories, and describes the
different output options supported by StillColor.
color image using the IMAQ PCI/PXI-1408 and National Instruments
StillColor technology, explains basic color theories, and describes the
different output options supported by StillColor.
Introduction
You can use two basic video camera types for color acquisition—RGB
cameras and composite color video cameras.
cameras and composite color video cameras.
An RGB camera delivers the three basic color components—red, green
and blue—on three different wires. This type of camera often uses three
independent CCD sensors to acquire the three color signals. RGB cameras
are used for very accurate color acquisition.
and blue—on three different wires. This type of camera often uses three
independent CCD sensors to acquire the three color signals. RGB cameras
are used for very accurate color acquisition.
A composite color camera transmits the video signal on a single wire. The
signal is composed of two components that are added together. These
components are:
signal is composed of two components that are added together. These
components are:
•
A monochrome video signal that contains the gray level information
from the image and the composite synchronization signals. This signal
is the same as a standard monochrome video signal, such as RS-170
(NTSC) or CCIR-601 (PAL).
from the image and the composite synchronization signals. This signal
is the same as a standard monochrome video signal, such as RS-170
(NTSC) or CCIR-601 (PAL).
•
A modulated signal that contains the color information from the image.
The format of this signal depends on your camera. The three main
color standards are as follows:
The format of this signal depends on your camera. The three main
color standards are as follows:
–
M-NTSC (also called NTSC), which is used mainly in the US
and Japan
and Japan
–
B/G-PAL (also called PAL), which is used mainly in Europe,
India, and Australia
India, and Australia
–
SECAM, which is used mainly in France and the former Soviet
Republics. SECAM is only used for broadcasting, so SECAM
countries often use PAL as the local color image format.
Republics. SECAM is only used for broadcasting, so SECAM
countries often use PAL as the local color image format.
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