mantithetical's profile - activity

Answered here.

I am trying out a slight variation of the example from http://docs.opencv.org/2.4.4-beta/doc/tutorials/introduction/desktop_java/java_dev_intro.html

    CascadeClassifier faceDetector = new CascadeClassifier("/haarcascade_frontalface_default.xml");
    Mat image = Highgui.imread(originalFile.getAbsolutePath());
    MatOfRect faceDetections = new MatOfRect();
    double w = ((double)originalCrop.getWidth());
    double h = ((double)originalCrop.getHeight());
    faceDetector.detectMultiScale(image, faceDetections, 3, 1, 
                   Objdetect.CASCADE_DO_CANNY_PRUNING , new Size(w/16, h/16), new Size(w/2, h/2));

From the API: scaleFactor – Parameter specifying how much the image size is reduced at each image scale.

Changing the scaleFactor changes what is detected. For example, for the following image: http://graphics8.nytimes.com/images/2013/04/02/world/MOSCOW/MOSCOW-articleLarge-v2.jpg

scaleFactor of 3 --> Gorbachev's face is not detected
scaleFactor of 2 --> Gorbachev's face is detected twice (one larger rectangle containing a smaller one)
scaleFactor of 1.01 ---> Gorbachev's face is detected once

How exactly does this work?

Following directions from Introduction to OpenCV, I am running into the this:

>make -j8
...
...
Linking CXX shared library ../../lib/libopencv_java244.dylib
ld: unknown option: -whole-archive
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [lib/libopencv_java244.dylib] Error 1
make[1]: *** [modules/java/CMakeFiles/opencv_java.dir/all] Error 2
make: *** [all] Error 2