Why MatOfPoint is list of points?

asked 2018-01-20 08:43:08 -0500

Tatev gravatar image

Hi, I'm quite new in OpenCV and image processing, I'm trying to understand findContours function and handle it's result, particularly I have to detect from image discrete graph and the number written for each edge. I guess I should start with finding contours and than somehow extract from it numbers. I have several questions.

  1. Why MatofPoint is list of points?
  2. I convert contour to the List<list<point>> and I wonder what defines the size of each list, as it can be any number 1 or 112...
  3. Is it possible to make matching beetwen screen coordinates and org.opencv.core.Point?

Could you, please, help me understand theese basic but main concepts, as I searched and read a lot but can't find answers.

P.S. Any blogs/links where I can find tutorials to successfully getting started with image processing wil be appreciated.

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take a look at the related tutorials

sturkmen gravatar imagesturkmen ( 2018-01-20 08:47:33 -0500 )edit

I've already read it, thanks a lot for your help! :)))

Tatev gravatar imageTatev ( 2018-01-20 09:07:48 -0500 )edit

"I have to detect from image discrete graph and the number written for each edge" -- can you explain a bit more ? like a freeman chain ?

berak gravatar imageberak ( 2018-01-20 09:23:27 -0500 )edit

Here is a sample image https://imgur.com/a/lHlwN I need to have coordinates of graph nodes and lenght for each edge.

Tatev gravatar imageTatev ( 2018-01-20 09:36:43 -0500 )edit