How to Find the min and max coordinates of an object in an image

How to find the minX,minY,maxX,maxY of an object in a binary image

Answer 1

[Matt J]

[I,J]=find(yourImage);

minIJ=min([I,J],[],1);

maxIJ=max([I,J],[],1);

[halima jamil]

thanks Matt J. One more thing. If I want to get min of I and min of J from your recommended code [ I,J]=find(yourImage);. Similarly max of I and J separately. what should I do for that.

[Image Analyst]

minI = minIJ(1);
minJ = minIJ(2);
maxI = maxIJ(1);
maxJ = maxIJ(2);

[Matt J]

 Imin=minIJ(1)
 Jmin=minIJ(2)

etc...

[Prathveraj Shetty]

hello,

I have a doubt . if i have coordinates of a point and a digital image (i.e., either black or white (bitmap)). How to find the distance between the point and each pixel of the image.

[Image Analyst]

Try this, where (xp, yp) are the coordinates of your single point.

[rows, columns, numberOfColorChannels] = size(yourImage);
[x, y] = meshgrid(1:columns, 1:rows);
distanceImage = sqrt((x-xp).^2 + (y-yp).^2);
imshow(distanceImage, []);

Answer 2

[Image Analyst]

Note: Matt's solution only works if you have only 1 object in your binary image. If you have multiple objects, use regionprops() and ask for the BoundingBox measurement. See my Image Segmentation Tutorial for a full demo: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

[Matt J]

Or the PixelList measurement.