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How to delete a QR CODE white margins?

asked 2014-02-25 02:18:11 -0500

smilencetion gravatar image

Hi,I'm new to OpenCV, is there a way to delete a QR CODE white margins?thx

just like from

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answered 2014-02-25 04:14:13 -0500

Haris gravatar image

updated 2014-02-25 10:34:44 -0500

  1. Create a mask image for the area to be cropped

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2.Find the bounding box for mask, you should do the following

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3.Crop the source using bound rect.

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Code:

   Mat src=imread("barcode.png",1);
   Mat thr,gray;
   cvtColor(src,gray,CV_BGR2GRAY);
   threshold( gray, thr, 50, 255, CV_THRESH_BINARY_INV );


   Size kernalSize (21,21);
   Mat element = getStructuringElement (MORPH_RECT, kernalSize, Point(1,1)  );
   morphologyEx( thr, thr, MORPH_CLOSE, element );

   vector< vector <Point> > contours;
   vector< Vec4i > hierarchy;
   findContours( thr, contours, hierarchy,CV_RETR_EXTERNAL, CV_CHAIN_APPROX_SIMPLE );
   Rect ROI=boundingRect(contours[0]); //Contour size  should bealways 1

   Mat crop=src(ROI);
   imwrite("crop.jpg",crop);
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Comments

excellent,ty so much

smilencetion gravatar imagesmilencetion ( 2014-02-25 04:23:52 -0500 )edit

@smilencetion, so mark it as solved !

berak gravatar imageberak ( 2014-02-25 04:29:03 -0500 )edit
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Asked: 2014-02-25 02:18:11 -0500

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Last updated: Feb 25 '14