How to capture image and record video using GPUImage 2?

Question

How to capture image with applied filter using GPUImage? For reference, below is the code which I am calling for get image:

func countdownFinished(_ view: LUCountdownView!) {
    let pictureOutput = PictureOutput()
    pictureOutput.keepImageAroundForSynchronousCapture = true
    pictureOutput.encodedImageFormat = .png
    pictureOutput.synchronousImageCapture()
}