contourArea() unit ??

asked 2015-08-19 15:47:27 -0600

NabeelKhan
71 ●2 ●4 ●9

Hi,

I am using contourArea() to get the area of a binary object

My question: does it return the number of pixels ?? Or if area then what is the unit of it

I need to convert the area into Mm2 and report it

Any help will be really appreciated

Thanks

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http://answers.opencv.org/question/58...

sturkmen ( 2015-08-19 15:54:49 -0600 )edit

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answered 2015-08-19 15:56:08 -0600

LBerger
9317 ●2 ●20 ●88 http://www.traimaocv.fr

updated 2015-08-19 16:11:53 -0600

contourArea unit is pixel. You can then mutiply area by your scale to have area in mm2. Area accuracy is given by perimeter I think : AREA = CONTOURAREA +/- ARCLENGTH

That's trivial case. Things can be more complicated if your scale is not linear : pixel near center haven't got same surface than pixel far from center....