Video formats, modes and bandwidth
MARLIN Technical Manual
V2.4.0
156
The frame rates in video modes 0 to 2 are specified and set fixed by IIDC
V1.3.
Frame rates Format_7
In video Format_7 frame rates are no longer fixed but can be varied dynam-
ically by the parameters described below.
The following formula is used to calculate for the CCD models the highest
frame rate in Format_7:
It assumes that the maximum frame rate is the inverse of the sum of all
events in a CCD, which take time such as:
Details are described in the next chapters:
•
Max. frame rate of CCD (theoretical formula)
•
Diagram of frame rates as function of AOI by constant width
•
Table with max. frame rates as function of AOI by constant width
Note
L
•
Different values apply for the different sensors.
•
Frame rates may be further limited by longer shutter
times and/or bandwidth limitation from the IEEE 1394
bus.
Formula 3: Frame rate calculation
Note
L
•
The time to transfer the storage to the vertical shift
register (Charge transfer time)
•
The time to shift out the dummy lines
•
The time to dump the lines outside the AOI
•
The time to shift out the lines of the AOI. (Scanning
time)
Note
L
Different parameters apply for different models.
framerate
In
framerate
CCD
1
T
Ch
eTrans
arg
T
Dummy
T
Dump
T
Scan
+
+
+
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