Smart Gui - Algorithm Training Material_rev1.pdf - 第141页

Copyright © ViT rox All Rights Reserved . Lead Ringer - Parameter Description 141 2. Extract ● The Extract option available depends on the “Compare T o” option selected. ● If “Compare T o” is set to “Other Leads” & O…

Lead Ringer - Parameter Description

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1. Compare To

● This option enable user to setup the comparison option

● Comparison “between leads” or “against an absolute threshold”

● 3 options as follow:

➔ Other Leads: Each lead is compared to all the other leads of the same row. The lead that

get a score 0 is recognized as the "base" of the row. We look at the difference between

leads.

➔ Other Leads (Invert Check): The invert check will compare leads that are failing against a

good template build from previous inspected components and determine if it is similar to it or

not (the threshold used to do the comparison and determine if there is a switch needed is

the threshold from the concerned page). If no leads are failing, we do not perform the invert

check.

➔ Threshold: Each lead is compared to the absolute threshold given by the user (separately

from the other leads of the row).

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2. Extract

● The Extract option available depends on the “Compare To” option selected.

● If “Compare To” is set to “Other Leads” & Other Leads (Invert Check), There are 3

Extract Options as follow:

➔ Mean Intensity Difference: we measure the mean intensity within the box and calculate the

difference with mean intensity of the "base" lead of the row (median lead). If the difference is

bigger/smaller of the threshold (depending on the threshold sense (high bad/low bad)), than

the lead will be called defective.

➔ Appearance Difference: we compare each pixel contained in the current box with the

corresponding pixels in the box of the "base" lead and calculate its difference. Then each

difference is summed up for all the pixel to produce an unique score.

➔ Curvature Difference: we calculate the curvature feature (distance between red channel

(Angle 1) and green channel (Angle 2) centre of gravity) in the current box, and then

measure the difference between the resulting value and the "base" lead of the row

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2. Extract

● If “Compare To” is set to “Threshold”, There are 2 Extract Option as follow:

● Mean Intensity: The mean intensity of the pixels contained in the box is measured and

compared with the threshold for each lead of the row.

● Curvature: the curvature feature is calculated for the current box and compared with the

threshold for each lead of the row