there is some questions about the example of connectedComponentsWithStats

[jsxyhelu]

in page 419(pdf)
1、when i use

 int i, nccomps = cv::connectedComponentsWithStats (
    img_edge, labels,
    stats, cv::noArray()
  );

OpenCV gvies me an ERROR,
I had change my code to

cv::Mat  centroids;
int nccomps = cv::connectedComponentsWithStats (
		img_edge, labels,
		stats, centroids
		);

2、i think

for( i = 1; i <= nccomps; i++ ) {

    colors[i] = Vec3b(rand()%256, rand()%256, rand()%256);

    if( stats.at<int>(i-1, cv::CC_STAT_AREA) < 100 )

      colors[i] = Vec3b(0,0,0); // small regions are painted with black too.

  }

may be changed to

for( i = 1; i < nccomps; i++ ) {
		colors[i] = Vec3b(rand()%256, rand()%256, rand()%256);
		if( stats.at<int>(i, cv::CC_STAT_AREA) < 100 )
			colors[i] = Vec3b(0,0,0); // small regions are painted with black too.
	}

and the below code gives me the right result.
am i right?thanks.

[zacniewski]

@jsxyhelu I think you are correct. I had the same problems and your solution gives proper results.
Best regards
Artur

[jsxyhelu]

that's OK!