Expert Answer:
s:
Pyramid mean shift + outline of detected edges seems does the job.
The code:
cv::Mat segmented, gray, edges;
cv::pyrMeanShiftFiltering(input, segmented, 15, 40);
cv::cvtColor(segmented, gray);
cv::Canny(gray, edges, 150, 150);
cv::cvtColor(edges, edgesBgr, CV_GRAY2BGR);
cv::Mat result = bgr - edgesBgr;
Here is a result i got:
Details: OpenCV Tutorial Part 6