Dalsa Genie HM640, User Manual

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Genie HM-HC Series-GigE Vision Camera Glossary of Terms
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Random Noise
Random noise is defined as the difference in peak to peak value for any single pixel repetitively sampled,
with the sensor in darkness. For digital cameras the measurement is based on at least 512 samples from any
pixel.
Router
A Router device forwards packets across networks. It operates at Layer 3 of the seven-layer OSI model.
Note that broadcast packets (such as GigE Vision Device Discovery message) do not cross routers.
SAT
Saturation Output Amplitude. SAT is the average maximum output level for a specified light input.
Scatter Gather
Host system memory allocated for frame buffers is virtually contiguous but physically scattered throughout
all available memory.
SNR
Signal to Noise Ratio. SNR measures the ratio between random noise and an arbitrary reference signal on
the transmission path or within a device.
Subnet
The subnet is identified by performing the logical AND of the IP address with its subnet mask.
TCP
Connection-oriented transport protocol providing robustness and reliability. Used by many Internet
application, such as HTML.
Trigger
A mechanism that initiates an action when an event occurs such as synchronizing an image acquisition to
an external event. A trigger generally causes a program routine to be executed such as the resetting of
camera exposure and/or the firing of a strobe light.
UDP
User Datagram Protocol is a connectionless transport protocol providing no guaranty of delivery or
reliability. GigE Vision Control Protocol and GigE Vision Stream Protocol are based on UDP.
Vignetting
Caused by a lens designed for a smaller camera sensor. Vignetting describes the gradual reduction in
exposure at the sensor edges. All machine vision lens specify the maximum sensor size usable before
vignetting occurs.
VLAN
A Virtual Local Area Network is a flexible arrangement where computers connected via a VLAN Ethernet
switch are not necessarily on the same LAN broadcast domain. Refer to the VLAN Ethernet switch
documentation for implementation and configuration details.
VPN
A virtual private network is a private data network that makes use of the public telecommunication
infrastructure, maintaining privacy through the use of a tunneling protocol and security procedures. The
idea of the VPN is to give the company the same capabilities at much lower cost by using the shared public
infrastructure rather than a private one. (source:
www.netunlimited.com/glossary.html )