ImageReader - discard some frames (decrease FPS)

Question

I have application which is using hardware camera to make some analysis in OpenCV. I am using ImageReader to get frames, and then I am passing them to algorithm. But I would like to get only let's say 1 or 2 frames per second from ImageReader.

I was trying to do it like this:

val imageReaderListener = ImageReader.OnImageAvailableListener { reader ->
    reader?.let {
        fps++
        if (fps > 30) {
            val image = it.acquireLatestImage()
            //mage calculations
            fps = 0
            image.close()
        }
    }
}

But unfortunately when ImageReader max images is set to 1 (I need only latest result to be shown to te user, so I do not need to increase this number), camera picture is getting freezed. So is there any way to decrease FPS going to ImageReader?