opencv/cv.go
func Threshold(src, dst *IplImage, threshold, max_value float64, threshold_type int) {
	C.cvThreshold(
		unsafe.Pointer(src),
		unsafe.Pointer(dst),
		C.double(threshold),
		C.double(max_value),
		C.int(threshold_type),
	)
}
func Threshold(src, dst *IplImage, threshold, max_value float64, threshold_type int) {
	C.cvThreshold(
		unsafe.Pointer(src),
		unsafe.Pointer(dst),
		C.double(threshold),
		C.double(max_value),
		C.int(threshold_type),
	)
}
/* Applies a fixed-level threshold to each array element. */