OpenCV detects a square with a complex background

Question

I am working on an Android application that recognizes the GO board and creates an SGF file .

I need to find the whole board to warp it and find the right lines and stones, as shown below.

_{(source: eighttytwo.axc.nl )}

I am now using an Opencv RGB mat and doing the following:

• separate channels

• Canny individual channels

  Imgproc.Canny(channel, temp_canny, 30, 100);
  

• merge (bitwise OR) all channels.

  Core.bitwise_or(temp_canny, canny, canny);
  

• find the outline of the board

However, I cannot detect the board sequentially, as some lines tend to disappear, as you can see in the figure below, black lines on the board and stones are clearly visible, but in some places the edges of the board are missing.

_{(source: eighttytwo.axc.nl )}

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* * 23-05-2016

, opencv, , !!! , , , opencv.

Answer 1

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