otTransparentNum = colors => {
                        let res = 0;
                        for (let i = 3; i < colors.length; i += 4) {
                            if (colors[i] >= 200) {
                                res++;
                            }
                        }
                        return res;
                    };

                    let maskEdgeL = null;
                    let maskEdgeR = null;
                    let maskEdgeT = null;
                    let maskEdgeB = null;
