find the edge of image with the help of axis(x,y) in opencv in android [closed]

asked 2015-06-18 06:23:48 -0600

prabhakar gravatar image

updated 2019-10-09 20:14:49 -0600

supra56 gravatar image

I have to color the object when it touched. For that follow the some basic concepts: I am getting coordinates of that portion where object is touched. After that I have to find the edges of touched object. Then fill color of that object. here I get the coordinates of touched portion.

int cols = mRgba.cols();
int rows = mRgba.rows();

int xOffset = (mOpenCvCameraView.getWidth() - cols) / 2;
int yOffset = (mOpenCvCameraView.getHeight() - rows) / 2;

int x = (int)event.getX() - xOffset;
int y = (int)event.getY() - yOffset;

x,y shows the coordinates of the touched portion but problem is to find the corners of object. For corners i use canny() method of opencv But no idea how to implement it by coding in opencv in android.

edit retag flag offensive reopen merge delete

Closed for the following reason question is not relevant or outdated by sturkmen
close date 2020-12-08 07:46:39.624503



I am probably not the only one who doesn't grasp what you are trying to do and I should definetly suggest you to improve your question and add more information. A good starting point can be to take a look at the FAQ.

StevenPuttemans gravatar imageStevenPuttemans ( 2015-06-18 09:44:32 -0600 )edit

@StevenPuttemans now i have improve my question

prabhakar gravatar imageprabhakar ( 2015-06-19 02:42:09 -0600 )edit

@prabhkar , i still don't get it either.

you calculation is the transformation from screen-coords to imge coords, so far so good.

what do you mean by 'axis' ? how is it related to canny ? what are you trying to achieve in the end ?

berak gravatar imageberak ( 2015-06-19 02:53:02 -0600 )edit

Canny will only highlight the edges in your image. you need findContours() to get the outlines as lists of contour points. then use floodFill() or similar to draw colors.

have a look at the clolor blob android example

berak gravatar imageberak ( 2015-06-19 07:17:59 -0600 )edit

@berak, it may be, I use wrong concept. Actually i want to implement, when i touch the object in image i want to get the edges of the object. for full description

prabhakar gravatar imageprabhakar ( 2015-06-24 23:42:01 -0600 )edit

just saying, - asking on SO will not help you here

berak gravatar imageberak ( 2015-06-29 02:51:51 -0600 )edit