Why aruco doesn't detect markers in my image

Question

I generate a series of aruco markers DICT_4X4_50 and I print them but when I launch the detector on this image for example, it doesn't work.. Though the marker is fairly visible:

int main(int argv, char** argc)
{
    Mat frame = imread(argc[1], CV_LOAD_IMAGE_COLOR);

    vector<int> markerIds;
    vector<vector<Point2f>> markerCorners, rejectedCandidates;

    Ptr<aruco::Dictionary> markerDictionary = aruco::getPredefinedDictionary(aruco::PREDEFINED_DICTIONARY_NAME::DICT_4X4_50);

    aruco::detectMarkers(frame, markerDictionary, markerCorners, markerIds);


    aruco::drawDetectedMarkers(frame, markerCorners, markerIds);
    imshow("Webcam", frame);
    waitKey(0);

}

Is the image not good enough or is there some parameters I can modify?

@ΦXocę웃Пepeúpaツ No I didn't calibrate my camera yet but I just want to detect the marker at the moment and it works when I give it a nice clear image — Ja_cpp, Aug 08 '17 at 09:49
aruco has a reasy to use module with a yml config that you yhould use before trying to detect any marker... — ΦXocę 웃 Пepeúpa ツ, Aug 08 '17 at 09:50
and dark room is not a good environment to do imageRecognition — ΦXocę 웃 Пepeúpa ツ, Aug 08 '17 at 09:51
@chris ya as I said it works with another images better than this one — Ja_cpp, Aug 08 '17 at 10:02
you could try convert the frame to grayscale/normalize it, there are many preprocessing things you can try. — chris, Aug 08 '17 at 10:06
@chris Okay I'll try that.. Aruco has many parameters, do you've any idea which parameters I can modify to hopefully detect the markers? — Ja_cpp, Aug 08 '17 at 12:36

score 2 · Accepted Answer · answered Aug 08 '17 at 21:41

I've checked the rejectedCandidates and I found out that it's detecting the marker but it was rejected for some reason!

So I moved to another marker which is Apriltags and it gives better result.. I don't know which library is the best out there but keep trying and see which one works for you well.

Why aruco doesn't detect markers in my image

1 Answers1