GoCV memory leaking on IMDecode function?

main.go

package main

import (
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	"time"

	"gocv.io/x/gocv"
)

func main() {
	http.HandleFunc("/file", FileHandler)
	http.ListenAndServe(":8080", nil)
}

func FileHandler(w http.ResponseWriter, r *http.Request) {
	fmt.Println(time.Now(), "FileHander")
	r.ParseMultipartForm(2 << 20)
	_, h, err := r.FormFile("file")
	if err != nil {
		fmt.Fprintln(w, err)
	}
	f, err := h.Open()
	bytes, err := ioutil.ReadAll(f)
	if err != nil {
		fmt.Fprintln(w, err)
	}
	f.Close()
	DecodeAndClose(bytes)
}

func DecodeAndClose(b []byte) {
	m, err := gocv.IMDecode(b, gocv.IMReadUnchanged)
	if err != nil {
		log.Fatal(err)
	}
	m.Close()
}