Why is my JavaCameraView is squeezed vertically?

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This is what the JavaCameraView looks like, my face is squeezed:

I use this code to achieve this effect:

 /**
 * Do processing after frame grabbing before rendering on screen
 * @Param inputFrame
 * @return
 */
@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {

    //For background subtraction
    mRgba = inputFrame.rgba();
    Imgproc.cvtColor(mRgba, mRgb, Imgproc.COLOR_RGBA2RGB); //the apply function will throw the above error if you don't feed it an RGB image
    sub.apply(mRgb, mFGMask, -1); //apply() exports a gray image by definition
    Imgproc.cvtColor(mFGMask, mRgba, Imgproc.COLOR_GRAY2RGBA);

    //transpose the matrix mRgba and put the result in trans
    Core.transpose(mRgba,trans);
   //flip trans about the x-axis
    Core.flip(trans, trans, 0);

    Core.flip(trans, trans, 1);
    Imgproc.resize(trans, trans, mRgba.size());
    //flip trans about the y-axis
    return trans;
}
private BackgroundSubtractorMOG2 sub = new BackgroundSubtractorMOG2(10, 25, false);
private Mat mRgb=new Mat();
private Mat mFGMask=new Mat();
private Mat mRgba=new Mat();
private Mat trans=new Mat();

Here is the interesting thing, I made the shutter button using:

Utils.matToBitmap(trans,previewBitmap);

to convert trans to a bitmap and display it. On most occasions, I was getting what is displayed in the live processing. But if I kept pressing "shutter", I was able to capture a snapshot like this( my face is NOT warped!):

Now the question is: How can I programmatically make my code so every photo I capture looks like the one above?