我是OpenCV的新手,我不知道如何遍历并更改所有颜色代码为RGB(0,0,0)
的黑色像素到白色RGB(255,255,255)
。是否有任何功能或方法来检查所有像素,如果RGB(0,0,0)
,则将其设置为RGB(255,255,255)
。
假设您的图像表示为形状为(height, width, channels)
的numpy
数组(cv2.imread
返回的内容(,则可以执行以下操作:
height, width, _ = img.shape
for i in range(height):
for j in range(width):
# img[i, j] is the RGB pixel at position (i, j)
# check if it's [0, 0, 0] and replace with [255, 255, 255] if so
if img[i, j].sum() == 0:
img[i, j] = [255, 255, 255]
一种更快的、基于掩码的方法如下:
# get (i, j) positions of all RGB pixels that are black (i.e. [0, 0, 0])
black_pixels = np.where(
(img[:, :, 0] == 0) &
(img[:, :, 1] == 0) &
(img[:, :, 2] == 0)
)
# set those pixels to white
img[black_pixels] = [255, 255, 255]
从每个像素中减去255,只得到正值
对于灰度和黑白图像
sub_array = 255*np.ones(28, dtype = int)
img_Invert = np.abs(np.subtract(img,sub_array))
cv.rectangle(img,(0,0),(img.shape[1],img.shape[0],(255,255,255),thickness=-1)
cv.imshow('img',img)