How to draw a rectangle contours only if largest than specific size

edit

may i know what should i write in condition if?

if ( what should i type here )

{

112 ... 132

}

I'm reluctant to just tell you, since you'll learn better if you figure it out yourself. But you have a Rect, with the functions and variables you can see here: http://docs.opencv.org/master/d2/d44/classcv_1_1Rect__.html#gsc.tab=0

If you want a minimum width of 200 and a minimum height of 300, what sort of if statement would that look like?

A small hint, look at a combination of the x y width and height attributes of the rectangle ;)

Sorry, i'm just start learn opencv few month and i still confuse about the code below. Would you help me explain about the below code please?

Rect minRect = boundingRect( Mat(contours[ largestIndex ]) );

What that does, is find the rectangle that completely contains the contour. So, in your example picture, no part of the larger contour is farther left than x=74, farther up than y=323, farther right than x=337, or farther down than y=479.

The Rectangle is described by four number, x and y, which are the x and y pixels of the top left corner ((74,323) for the example image), and the width and height of the rectangle.

this is my code, is that true?

http://paste.ofcode.org/w3cZgTE7kkyM9...

That almost works. First, that is only one of your rectangles. You'll need to add the second one inside a second if statement.

Secondly, when do you show the image? Make sure it happens when you actually want it to be shown.

Lastly, double check the width and height. They aren't the same numbers you used here. Perhaps you meant to do that, perhaps it's a typo.

May i know what means the width and height aren't the same numbers used here?

Well, your if statement uses 100300, when your example was 200300. That's all. I wasn't sure if you meant to do that, or if it was a typo.

oh i see, thanks for reminding.