How to use Maximum angle threshold?

Hello, i wanna ask about MaximumAngleThreshold in http://www.mathworks.com/help/vision/ref/vision.cornerdetectorclass.html

How can I detect the corner with other angle in degree except those mentioned? e.g. 180 degree,270 degree. Thanks in advance

Answer 1

[Image Analyst]

Now 180 is not really a corner, is it? It's totally straight. And 270 is the same as 90, right?

[tedy]

how if i wanna detect both of 270 and 90? is still the same? how to implement each of them?

[Anand]

90 and 270 are the same...just set the angle to 90 and you'll be fine.

[tedy]

no,i mean how to detect 90 in order to get number 1 (as its sign) and 270 to get number 3. so,if i set the maximum angle as 90 both of them, it can't be differentiate which is 90 for number 1 and which is 90 for number 3?

[Image Analyst]

I haven't used the tool. I don't know if it can distinguish between "inside" corners like

0 0 1 1
0 0 1 1
1 1 1 1
1 1 1 1

which is perhaps what you consider a 270 degree angle, and "outside" corners like

1 1 0 0
1 1 0 0
0 0 0 0
0 0 0 0

which perhaps you consider a 90 degree angle. You'll have to call the Mathworks and ask them or figure it out yourself.

[tedy]

how can i call the mathworks? email or what?

[Image Analyst]

Either. Contact info: http://www.mathworks.com/company/aboutus/contact_us/