def change_hue(img, hue_angle):
'''
Changes Hue based on provided hue offset; Hue Angle must be provided in *radians* !
'''
# convert to HSI
out_img = rgb_to_hsi(img)
# get Hue angle displacement in radians; only change 0 <= x <= 2pi
if (hue_angle != 0):
change = abs(hue_angle) % (2 * math.pi)
else:
change = 0
# adjust hue for every pixel
for row in range(out_img.shape[0]):
for col in range(out_img.shape[1]):
# making sure 0 <= hue <= 2pi
if (out_img[row, col, 0] + change > 2 * math.pi):
out_img[row, col,
0] = out_img[row, col, 0] + change - 2 * math.pi
elif (out_img[row, col, 0] + change < 0):
out_img[row, col,
0] = out_img[row, col, 0] + change + 2 * math.pi
else:
out_img[row, col, 0] = out_img[row, col, 0] + change
# convert to RGB
out_img = hsi_to_rgb(out_img)
return out_img
def change_saturation(img, sat):
'''
Changes saturation level of HSI image
'''
# convert to HSI
out_img = rgb_to_hsi(img)
# Perform operation only if change isn't 0
if (sat != 0):
# adjust saturation for every pixel
for row in range(out_img.shape[0]):
for col in range(out_img.shape[1]):
result = out_img[row, col, 1] + sat
# make sure that the final result stays 0 <= S <= 1
if (result > 1):
out_img[row, col, 1] = 1
elif (result < 0):
out_img[row, col, 1] = 0
else:
out_img[row, col, 1] = result
# convert to RGB
out_img = hsi_to_rgb(out_img)
return out_img
def change_saturation(image: str, sat: int):
''' sat can be negative'''
global x, img, img_size, hsi, rgb_output
## Reading input image
x = cv2.imread(image)
img = np.array(x, dtype=np.double)
img_size = img.shape
## Confirm and adjust so sat is greater or equal to 0 and less than or
## equal to 1
if (sat > 1):
sat = sat % 1
elif (sat < 0):
sat = (sat % 1) + 1
## Converting to HSI space
hsi = rgb_to_hsi(img)
## Applying change in saturation to output image
for i in range(img_size[0]):
for j in range(img_size[1]):
hsi[i, j, 1] = (((hsi[i, j, 1] / 255.0) + sat) % 1.0) * 255.0
## Converting back into RGB space
rgb_output = hsi_to_rgb(hsi)
## Showing and writing output image
cv2.imshow('rgb image with hue changed', rgb_output)
cv2.imwrite('changed_sat_output.jpg', rgb_output)
cv2.waitKey(0)
cv2.destroyAllWindows()
def change_hue(image: str, hue_angle: int):
''' hue_angle must be given in degrees'''
global x, img, img_size, hue, hsi, rgb_output
## Reading input image
x = cv2.imread(image)
img = np.array(x, dtype=np.double)
img_size = img.shape
## Confirming and adjusting hue so it is within range of [0, 360]
hue = hue_angle
if (hue > 360):
hue = hue % 360
elif (hue < 0):
hue = (hue % 360) + 360
## Converting to HSI space
hsi = rgb_to_hsi(img)
## Applying change in hue to output image
for i in range(img_size[0]):
for j in range(img_size[1]):
hsi[i, j,
0] = (((hsi[i, j, 0] / 255.0) + (hue / 360.0)) % 1.0) * 255.0
## Converting back into RGB space
rgb_output = hsi_to_rgb(hsi)
## Showing and writing output image
cv2.imshow('rgb image with hue changed', rgb_output)
cv2.imwrite('changed_hue_output.jpg', rgb_output)
cv2.waitKey(0)
cv2.destroyAllWindows()
def main(*arg):
imgName = input("Please enter image name: ")
img = cv2.imread(imgName, 1)
# to run independently (from main() ), needs to have rgb_to_hsi.py to be in the same directory!
img1 = rgb_to_hsi(img)
out = hsi_to_rgb(img1)
cv2.imshow('out', out)
cv2.waitKey(0)