import cv2

import sys

import numpy as np

def nothing(x):

pass

useCamera=False

# Check if filename is passed

if (len(sys.argv) <= 1) :

print ("'Usage: python hsvThresholder.py <ImageFilePath>' to ignore camera and use a local image.")

useCamera = True

# Create a window

cv2.namedWindow('image')

# create trackbars for color change

cv2.createTrackbar('HMin','image',0,179,nothing) # Hue is from 0-179 for Opencv

cv2.createTrackbar('SMin','image',0,255,nothing)

cv2.createTrackbar('VMin','image',0,255,nothing)

cv2.createTrackbar('HMax','image',0,179,nothing)

cv2.createTrackbar('SMax','image',0,255,nothing)

cv2.createTrackbar('VMax','image',0,255,nothing)

# Set default value for MAX HSV trackbars.

cv2.setTrackbarPos('HMax', 'image', 179)

cv2.setTrackbarPos('SMax', 'image', 255)

cv2.setTrackbarPos('VMax', 'image', 255)

# Initialize to check if HSV min/max value changes

hMin = sMin = vMin = hMax = sMax = vMax = 0

phMin = psMin = pvMin = phMax = psMax = pvMax = 0

# Output Image to display

if useCamera:

cap = cv2.VideoCapture(0)

# Wait longer to prevent freeze for videos.

waitTime = 330

else:

img = cv2.imread(sys.argv[1])

output = img

waitTime = 33

while(1):

if useCamera:

# Capture frame-by-frame

ret, img = cap.read()

output = img

# get current positions of all trackbars

hMin = cv2.getTrackbarPos('HMin','image')

sMin = cv2.getTrackbarPos('SMin','image')

vMin = cv2.getTrackbarPos('VMin','image')

hMax = cv2.getTrackbarPos('HMax','image')

sMax = cv2.getTrackbarPos('SMax','image')

vMax = cv2.getTrackbarPos('VMax','image')

# Set minimum and max HSV values to display

lower = np.array([hMin, sMin, vMin])

upper = np.array([hMax, sMax, vMax])

# Create HSV Image and threshold into a range.

hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)

mask = cv2.inRange(hsv, lower, upper)

output = cv2.bitwise_and(img,img, mask= mask)

# Print if there is a change in HSV value

if( (phMin != hMin) | (psMin != sMin) | (pvMin != vMin) | (phMax != hMax) | (psMax != sMax) | (pvMax != vMax) ):

print("(hMin = %d , sMin = %d, vMin = %d), (hMax = %d , sMax = %d, vMax = %d)" % (hMin , sMin , vMin, hMax, sMax , vMax))

phMin = hMin

psMin = sMin

pvMin = vMin

phMax = hMax

psMax = sMax

pvMax = vMax

# Display output image

cv2.imshow('image',output)

# Wait longer to prevent freeze for videos.

if cv2.waitKey(waitTime) & 0xFF == ord('q'):

break

# Release resources

if useCamera:

cap.release()

cv2.destroyAllWindows()