Opencv Face detection show different result between win and linux

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I'm coding at Win10. and run the project at Linux. It's worked fine at win10 env, and got some problem with Linux system (centos 7). and got same problem in 2 different linux server. env: java8 + opencv2.4.13 + tomcat8.

1.Throw exception when runing cvtColor() in Linux. like this:

Mat image = Highgui.imread(inputimg);  //Only have 1 channel in Linux. and the same pic have 3 channels in win.
Imgproc.cvtColor(image, image , Imgproc.COLOR_RGB2GRAY); //throw exception at this line

It's throwing this:

throws java.io.FileNotFoundException]: CvException [org.opencv.core.CvException: cv::Exception: /home/qh/opencv/opencv-2.4.13/modules/imgproc/src/color.cpp:3739: error: (-215) scn == 3 || scn == 4 in function cvtColor]
CvException [org.opencv.core.CvException: cv::Exception: /home/qh/opencv/opencv-2.4.13/modules/imgproc/src/color.cpp:3739: error: (-215) scn == 3 || scn == 4 in function cvtColor

The same picture. have 3 channels in windows. only have 1 channel in Linux.(I print Mat.channels() in java. It shows only 1 channel in linux. ). (scn means count of image channels in c++ source code. and COLOR_RGB2GRAY need input image file have 3 or 4 channels. )

2.Then I delete cvtColor() from my code. now it look like this. and got anthor situation.

Mat image = Highgui.imread(inputimg);
        CascadeClassifier faceDetector =  new CascadeClassifier(dataxml);
        MatOfRect faceDetections = new MatOfRect();
        faceDetector.detectMultiScale(image, faceDetections);

I'm using the same code , same picture. And the program can correctly detect faces in windows. but always detect 0 faces in linux.

Why same code , same picture got different result.