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Standard event processing is based on 3x3 pixel neighborhood event detection and extraction. A local maximum is specifically defined as any pixel, p0, that meets the following comparison rules.
|p0 > p6||p0 > p7||p0 > p8|
|threshold||p0 > p5|
where the pixels are in READX and READY coordinates. Note: This may be different than the flight software. Any event that meets the above comparison rules is written into the event list as a 9 pixel vector with the pixels arranged from p0 to p8 as illustrated above.
Events are not detected at quadrant boundaries (i.e. the boundaries between regions read by a single output node). Therefore there will always be a 2 pixel gap in images where nodes meet (one pixel on each side of the node). Events are also not detected at the edges of windows or full-frames. Note that events are detected at quadrant boundaries for the flight instrument (but no effect is made to adjust for diffential gain between output nodes).