【opencv-python 叠加图片展示】

叠加图片展示

np.vstack()
按垂直方向（行顺序）堆叠数组构成一个新的数组
np.hstack()
按水平方向（列顺序）堆叠数组构成一个新的数组
可以把图片叠加展示

img = cv2.imread("Resources/majiang.JPG")
# imggray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
#给图片缩小一下
img = cv2.resize(img,(0,0),None,0.3,0.3)
imgHor = np.hstack((img,img))
imgVer = np.vstack((img,img))

cv2.imshow("Horizontal",imgHor)
cv2.imshow("Vertical",imgVer)
cv2.waitKey(0)

因此可以写一个函数来展示图片

# scale为传入的缩小放大值，imgArray为传入的图片数组
def stackImages(scale, imgArray):
    rows = len(imgArray)
    cols = len(imgArray[0])
   # 判断是否为单图片
    rowsAvailable = isinstance(imgArray[0], list)
    width = imgArray[0][0].shape[1]
    height = imgArray[0][0].shape[0]
    if rowsAvailable:
        for x in range(0, rows):
            for y in range(0, cols):
            # 判断图片xy是否和00图片一样大，如果一样大则按照原先尺度缩放，否则不变
                if imgArray[x][y].shape[:2] == imgArray[0][0].shape[:2]:
                    imgArray[x][y] = cv2.resize(imgArray[x][y], (0, 0), None, scale, scale)
                else:
                    imgArray[x][y] = cv2.resize(imgArray[x][y],
                                                (imgArray[0][0].shape[1], imgArray[0][0].shape[0]), None, scale,
                                                scale)
                 #判断图片有几个通道，shape0,1通道为长宽，2为颜色，如果没有颜色设置为灰度图
                if len(imgArray[x][y].shape) == 2: imgArray[x][y] = cv2.cvtColor(imgArray[x][y],
                                                                                 cv2.COLOR_GRAY2BGR)
        imageBlank = np.zeros((height, width, 3), np.uint8)
        hor = [imageBlank] * rows
        hor_con = [imageBlank] * rows
        for x in range(0, rows):
        #按水平方向（列顺序）堆叠数组构成一个新的数组
            hor[x] = np.hstack(imgArray[x])
        #hor垂直方向塞入
        ver = np.vstack(hor)
    else:
        for x in range(0, rows):
            if imgArray[x].shape[:2] == imgArray[0].shape[:2]:
                imgArray[x] = cv2.resize(imgArray[x], (0, 0), None, scale, scale)
            else:
                imgArray[x] = cv2.resize(imgArray[x], (imgArray[0].shape[1], imgArray[0].shape[0]), None, scale,
                                         scale)
            if len(imgArray[x].shape) == 2: imgArray[x] = cv2.cvtColor(imgArray[x], cv2.COLOR_GRAY2BGR)
        hor = np.hstack(imgArray)
        ver = hor
    return ver

展示效果

img = cv2.imread("Resources/majiang.JPG")
imgGray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
imgStack = stackImages(0.2, ([img, imgGray, img], [img, img, img]))
cv2.imshow("ImageStack", imgStack)
cv2.waitKey(0)