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Hi

I use the image I attached.

I use this line to get the sum of pixels from row 307 to 366, at columns from 464 to 490

for col = 464 : 490

heights(col) = sum(rgbImage(366,col) - rgbImage(307,col));

end

This subtraction would give us 59 pixels and with a calibration factor of 0,042 it would give us around 2,48 mm for all the columns.

When I export the values to an excel file I get

If you multiply the below values with 0,042 you only get around 6 values acceptable and the closest to 2,5mm.

Why this incongruency???

By measuring heights(col), I should get 59 pixels multiplied by 0,042 I would get around 2,47 mm. Why I don't get those values when I export them to Excel??

Any ideas?

1

5

7

10

13

21

31

38

48

54

58

65

69

76

75

73

69

67

66

58

52

45

39

33

28

24

18

14

Image Analyst
on 24 Feb 2019

See attached spatial calibration demo. Adapt as needed.

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