# grayscale 영상 생성 비교
import numpy as np, cv2, matplotlib.pyplot as plt

# 50 x 512 영상 생성
image_progressive = np.zeros((50, 512), np.uint8)
image_stepwise    = np.zeros((50, 512), np.uint8)

rows, cols = image_progressive.shape[:2]

for i in range(rows):  # 행렬 전체 조회
    for j in range(cols):
        image_progressive[i, j] = j//2     # 화소값 점진적 증가
        image_stepwise[i, j] = (j//20)*10  # 계단 현상 증가
    pass
pass

# 이미지들을 비교하여 출력
plt.figure(figsize=(12, 4))

# 이미지 출력
plt.subplot(2, 1, 1)
plt.title('Grayscale continuous')
plt.imshow( image_progressive, cmap="gray") 
plt.axis('off') 

plt.subplot(2, 1, 2)
plt.title('Grayscale discrete')
plt.imshow( image_stepwise, cmap="gray")
plt.axis('off')

plt.tight_layout()
plt.show()