The property values are computed as follows:
•active_w: Total width of the pixel-active region. In this case, it is 3840 + 4 (LI) + 12 (left margin) + 0 (right margin) = 3856.
•active_h: Total height of the pixel-active region. In this case, it is 2160 + 8 (OB) + 6 (Ignored Area Effective Pixel + 50 (VBP)) * 2 = 4448.
num_of_lines_offset_0, to define how many rows between these two exposure frames.
it represents vertical blanking period and its correct value makes sure that Frame Interval > Long Exposure for LEF.
it’s the same number of VBP rows appear at the end of a long exposure frame and at the start of a short exposure frame. if you configure num_of_lines_offset_0=50, there’ll be 50-rows at the end of a long exposure frame and 50-rows at the start of a short exposure frame.
the other settings, such as num_of_ignored_lines, num_of_ignored_pixels, num_of_left/right_margin_pixels…
you may consider they’re the start-point for VI cropping these exposure frames.
num_of_ignored_lines = (Optical Black + Ignored Area Effective Pixel rows)