Cooling effect.py

import cv2
import numpy as np

from scipy.interpolate import UnivariateSpline

img = cv2.imread("cat.png")

#Cooling effect
class CoolingFilter():
    def __init__(self):
        """Initialize look-up table for curve filter"""
        # create look-up tables for increasing and decreasing a channel
        self.incr_ch_lut = self._create_LUT_8UC1([0, 64, 128, 192, 256],
                                                 [0, 70, 140, 210, 256])
        self.decr_ch_lut = self._create_LUT_8UC1([0, 64, 128, 192, 256],
                                                 [0, 30,  80, 120, 192])

    def render(self, img_rgb):
        c_r, c_g, c_b = cv2.split(img_rgb)
        c_r = cv2.LUT(c_r, self.incr_ch_lut).astype(np.uint8)
        c_b = cv2.LUT(c_b, self.decr_ch_lut).astype(np.uint8)
        img_rgb = cv2.merge((c_r, c_g, c_b))


       
        c_h, c_s, c_v = cv2.split(cv2.cvtColor(img_rgb, cv2.COLOR_RGB2HSV))
        c_s = cv2.LUT(c_s, self.incr_ch_lut).astype(np.uint8)

        return cv2.cvtColor(cv2.merge((c_h, c_s, c_v)), cv2.COLOR_HSV2RGB)

    def _create_LUT_8UC1(self, x, y):
        """Creates a look-up table using scipy's spline interpolation"""
        spl = UnivariateSpline(x, y)
        return spl(range(256))
print('Cooling Effect Applied.')

y = CoolingFilter()
Cool = y.render(img)

#comparing original vs resized
cv2.imshow('ORIGINAL',img)
cv2.imshow('Cooling effect',Cool)

cv2.waitKey(0)
cv2.destroyAllWindows()