[Error] 'chrono' is not a namespace-name code example
Example: error: ‘cv’ is not a namespace-name using namespace cv;
#include <opencv/cv.h>
NOTE: you may forgotten to include above header, thats why you got below error.
prashad@ubuntu:~/test$ g++ create_ipl_image.cpp `pkg-config opencv cvblob --cflags --libs`
create_ipl_image.cpp:4:17: error: ‘cv’ is not a namespace-name
using namespace cv;