docs: public static <T extends ImageGray<T>>
  	FastCornerDetector<T> fast(int pixelTol, int minCont, Class<T> imageType)
  	{
  		FastCornerInterface helper;
  		if( imageType == GrayF32.class ) {
  			if (minCont == 9) {
  				helper = new ImplFastCorner9_F32(pixelTol);
  			} else if (minCont == 10) {
  				helper = new ImplFastCorner10_F32(pixelTol);
  			} else if (minCont == 11) {
  				helper = new ImplFastCorner11_F32(pixelTol);
  			} else if (minCont == 12) {
  				helper = new ImplFastCorner12_F32(pixelTol);
  			} else {
  				throw new IllegalArgumentException("Specified minCont is not supported");
  			}
  		} else if( imageType == GrayU8.class ){
  			if (minCont == 9) {
  				helper = new ImplFastCorner9_U8(pixelTol);
  			} else if (minCont == 10) {
  				helper = new ImplFastCorner10_U8(pixelTol);
  			} else if (minCont == 11) {
  				helper = new ImplFastCorner11_U8(pixelTol);
  			} else if (minCont == 12) {
  				helper = new ImplFastCorner12_U8(pixelTol);
  			} else {
  				throw new IllegalArgumentException("Specified minCont is not supported");
  			}
  		} else {
  			throw new IllegalArgumentException("Unknown image type");
  		}
  		return new FastCornerDetector(helper);
  	}