Partial Scan Vertical Timing - JAI AD-131GE User Manual

8.4.3

Partial Scan Vertical Timing

The following chart shows the vertical timing of partial scanning in the continuous mode. The
horizontal timing for partial scan is the same as full scan. This is common for Channel 1 and
Channel 2
If JAI Partial Scan = True,
1L : 1LVAL period
1L = 1660 clock (32.344μs)
How to calculate total line number and frame rate on variable partial scan mode
Partial scan Offset Y
Height
Total lines = ① + ② + ③ + ④ + ⑤ + ⑥ + 1
Where,
① OB period in the upper part of the frame= 4L
② Fast dump period for the upper part=
③ Read out lines = Height + G
④ Fast dump period for the lower part=
⑤ Even adjustment for total line=
⑥ Dummy transfer period = 5L
Frame rate (fps) = Horizontal Frequency / Total lines
where, Horizontal Frequency
AD-131GE
OB: Optical Black
Fig.29 Vertical Timing for partial scan
0 line to 958 line
8 lines to 966 lines
⑤=1, If ①+②+③+④+⑥+ 1 is odd and ⑤=0, if ①+②+③+④+⑥+1 is
even.
Round up
G=1, if Height is odd and G=0, if Height is even.
Round up {((966 –(OffsetY)- (Height) +2))/5)
30.918KHz
34
{(4+(Offset) - 1)/5}