cv_trackbar.py

#! /usr/bin/env python
import cv2

class TrackbarData:
    def __init__(self, name='Trackbar', window='Window', value=0, count=100):
        self.value = value
        cv2.createTrackbar(name, window, value, count, self.update)
    def update(self, value):
        self.value = value

cv2.namedWindow('image')
T1 = TrackbarData('H*x/50', 'image', 50)
T2 = TrackbarData('S*x/50', 'image', 50)
T3 = TrackbarData('V*x/50', 'image', 50)

cap = cv2.VideoCapture(0)
while cap.isOpened():
    read, image = cap.read()
    if not read:
        break
    ihsv = cv2.cvtColor(image, cv2.COLOR_BGR2HSV)
    ihsv[...,0] *= T1.value/50.
    ihsv[...,1] *= T2.value/50.
    ihsv[...,2] *= T3.value/50.
    image = cv2.cvtColor(ihsv, cv2.COLOR_HSV2BGR)
    cv2.imshow('image', image)
    # If ESC key pressed Key=0x1B, Key=0x10001B under OpenCV linux
    if cv2.waitKey(1) & 0xFF == 27: # aka ESCAPE
        break