Add reacts to black better than white color

1

I don’t get how this impacts heavily based on add(). See the example below:
Original image

0-1-0
0-1-02152×1206 56.4 KB

2

0-2-0
0-2-02142×1198 50 KB

3

difference after difference = cv2.add(previous, current)
image

4

So when I did white, See here:

0-1-0
0-1-02152×1206 58 KB

5

0-2-0
0-2-02142×1198 51.1 KB

6

which result as this:
image

How come there’s 5 types to compare the frame when I just want to detect the difference without any extra?

If this is duplicate topic, could you kindly share the link?

Thank you so much for your time too!

7

Sorry for multiple replies. This website won’t let me upload 6 pictures in one topic due to new member. I understand though

9

ouch. (it hurts already, reading this)

you have binary images here. boolean logic applies.
(rather think: a OR b, instead of ‘+’)

white+white=white;
white+black=white;
black+black=black

10

damn, ill go back and read doc again. thank you!

Is there any that just return the difference only? like

previous frame: [[30, 20, 10], [30, 20, 50]] 
current frame: [[30, 20, 10], [30, 20, 30]]

returns [30, 20, 30]