无法在 OpenCV 中移动轨迹栏。他们立即回到零。

Question

代码没有给我任何错误，但我无法移动轨迹栏来找到我喜欢的值。我已经完全阅读了文档，但没有找到任何有用的信息。我正在尝试使用轨迹栏为我的颜色范围找到一个好的上限值和下限值。它应该很简单。

rh 例如表示红色上限为红色上限。

这是我的代码：

import cv2
import numpy as np

def nothing(x):
    return()


cap = cv2.VideoCapture('video.MOV')


while(1):

    #Gets retval and frames from each video 

    ret ,frame = cap.read()

    #Check to see if retval is not None or empty
    if not ret:
        break;

    trackbar = np.zeros((300,512,3), np.uint8)
    trackbar2 = np.zeros((300,512,3), np.uint8)
    cv2.namedWindow("trackbar")
    cv2.namedWindow("trackbar2")


    cv2.createTrackbar('RL','trackbar',0,255,nothing)
    cv2.createTrackbar('GL','trackbar',0,255,nothing)
    cv2.createTrackbar('BL','trackbar',0,255,nothing)

    cv2.createTrackbar('RH','trackbar2',0,255,nothing)
    cv2.createTrackbar('GH','trackbar2',0,255,nothing)
    cv2.createTrackbar('BH','trackbar2',0,255,nothing)


    r = cv2.getTrackbarPos('RL','trackbar')
    g = cv2.getTrackbarPos('GL','trackbar')
    b = cv2.getTrackbarPos('BL','trackbar')

    rh = cv2.getTrackbarPos('RH','trackbar2')
    gh = cv2.getTrackbarPos('GH','trackbar2')
    bh = cv2.getTrackbarPos('BH','trackbar2')

    trackbar[:] = [b,g,r]
    trackbar2[:] = [bh,gh,rh]



    boundaries = [([r,g,b],[rh,gh,bh])]

    for (lower,upper) in boundaries:     
            lower = np.array(lower, dtype = "uint8")   
            upper = np.array(upper, dtype = "uint8")

            mask = cv2.inRange(frame,lower,upper)
            output = cv2.bitwise_and(frame, frame, mask = mask)
            cv2.imshow("video", np.hstack([frame, output]))   




    if (cv2.waitKey(1) & 0xFF) == ord("q"):
        break


cv2.destroyAllWindows()

Answer 1

正如烧杯所提到的，我在循环中进行了启动，所以我只是将它们移到了外面并且它起作用了：工作代码如下：

import cv2
import numpy as np

def nothing(x):
    return()


cap = cv2.VideoCapture('movie.MOV')

trackbar = np.zeros((300,512,3), np.uint8)
trackbar2 = np.zeros((300,512,3), np.uint8)
cv2.namedWindow("trackbar")
cv2.namedWindow("trackbar2")


cv2.createTrackbar('RL','trackbar',0,255,nothing)
cv2.createTrackbar('GL','trackbar',0,255,nothing)
cv2.createTrackbar('BL','trackbar',0,255,nothing)

cv2.createTrackbar('RH','trackbar2',0,255,nothing)
cv2.createTrackbar('GH','trackbar2',0,255,nothing)
cv2.createTrackbar('BH','trackbar2',0,255,nothing)



while(1):

    #Gets retval and frames from each video 

    ret ,frame = cap.read()

    #Check to see if retval is not None or empty
    if not ret:
        break;


    r = cv2.getTrackbarPos('RL','trackbar')
    g = cv2.getTrackbarPos('GL','trackbar')
    b = cv2.getTrackbarPos('BL','trackbar')

    rh = cv2.getTrackbarPos('RH','trackbar2')
    gh = cv2.getTrackbarPos('GH','trackbar2')
    bh = cv2.getTrackbarPos('BH','trackbar2')

    trackbar[:] = [b,g,r]
    trackbar2[:] = [bh,gh,rh]



    boundaries = [([r,g,b],[rh,gh,bh])]

    for (lower,upper) in boundaries:     
            lower = np.array(lower, dtype = "uint8")   
            upper = np.array(upper, dtype = "uint8")

            mask = cv2.inRange(frame,lower,upper)
            output = cv2.bitwise_and(frame, frame, mask = mask)
            cv2.imshow("video", np.hstack([frame, output]))   




    if (cv2.waitKey(1) & 0xFF) == ord("q"):
        break


cv2.destroyAllWindows()

无法在 OpenCV 中移动轨迹栏。他们立即回到零。

Can't move trackbars in OpenCV. They instantly go back to zero.

python

image-processing

trackbar

color-palette

opencv3.0