Imgproc.undistort() seems missing in OpenCV4

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Java video app uses

Imgproc.undistort(frameIn,frameout_undist,cameraMatrix,distCoeffs,camUndistortMatrix);

to flatten a radially distorted image with versions up to OpenCV 3.4.3. My upgrade to OpenCV 4.1.1 just broke this call and I cannot find the equivalent function in the new API. I provide the distorted image frameIn, a buffer for the undistorted image frameout_undist, the camera and distance coefficients cameraMatrix and distCoeffs, and the optimal undistortion matrix derived from Calib3d.getOptimalNewCameraMatrix(). I was hoping someone would point me to the approve way to undistort images in Opencv 4.