需求分析：
在一个背景图上(optional) 进行绘制，可以使用圆形刷子或画矩形，也可以使用圆形橡皮；圆形刷子或橡皮可以调整半径；
可以保存结果图以及前景图(即去除掉背景)；
本程序可以用于为图像制作mask，因此也对“将mask作用于图像”进行了实现；
所需库：
import os
import sys
import cv2
import numpy as np
完整源码及注释：
"""
绘图工具
基于一张背景图（optional），绘制圆形或矩形，并可保存完整图及前景图；
可以选择前景图的保存模式（详见saveForeground函数的mode参数）
按键说明：
按键'm'：切换绘图模式，绘制圆形或者矩形
按键'+'，'-'：增加或减小圆形的半径
案件'e'：打开或关闭橡皮模式
按键'q'：退出
"""
import os
import sys
import cv2
import numpy as np
class Painter:
def __init__(self, img_size=(1080, 1920, 3), mode='circle', background=None, circle_radius=20, win_name='my Drawing Board', save_path=None, color=(1,1,255), show_all_layers=False):
"""
:param img_size：画板大小，若指定background则忽略此参数
:param mode: 'circle'画圆点，'rectangle'画矩形
:param background: 画板的背景图片地址
:param circle_radius：‘circle'模式下圆形的半径
:param win_name：窗口名
:param save_path：绘图结果保存地址
:param color：画笔颜色
:param show_all_layers：是否显示前景图层以及前景辅助图层
"""
# （1）基本信息
self.mode = mode
self.win_name = win_name
self.save_path = save_path
self.brush_color = color
self.eraser_color = (1,1,1)
self.circle_radius = circle_radius
self.show_all_layers = show_all_layers
# （2）图层
self.layer_back = cv2.imread(background) if background is not None else np.zeros(img_size, dtype=np.uint8) # 背景图层
self.layer_fore_0 = np.zeros(self.layer_back.shape, dtype=np.uint8) # 前景图层
self.layer_fore_1 = np.zeros(self.layer_back.shape, dtype=np.uint8) # 前景暂留图层（用于显示但是不作为最终前景图片的辅助图层）
# （3）状态信息
self.eraser = False # 是否使用橡皮功能
self.switch_fromCircle = False # 是否刚刚结束circle或eraser模式
self.click = False # 鼠标是否产生了一次“按下—松开”的click过程
self.drawing = False # 是否处于绘制状态
self.x0, self.y0 = -1, -1 # （rectangle模式）记录鼠标按下时的起始位置，即矩形的起始顶点
self.x1, self.y1 = -1, -1 # （rectangle模式）记录上一次鼠标的位置，即当前矩形的终止顶点
self.x2, self.y2 = -1, -1 # （circle模式）记录"circle"模式且未绘制状态下，鼠标上次的位置
# 鼠标事件
def mouseEvent(self, event, x, y, flag, param):
# （0）清除上一次circle或eraser遗留的痕迹
if self.switch_fromCircle:
cv2.circle(self.layer_fore_1, (self.x2, self.y2), radius=self.circle_radius, color=(0,0,0), thickness=-1)
self.switch_fromCircle = False
# （1）鼠标左键按下事件——开启绘图状态
if event == cv2.EVENT_LBUTTONDOWN:
self.drawing = True
self.x0, self.y0 = x, y
self.x1, self.y1 = x, y
self.x2, self.y2 = -1, -1
# （2）鼠标移动事件——绘图
elif event == cv2.EVENT_MOUSEMOVE:
# （2.1）绘制模式
if self.drawing:
# 使用橡皮
if self.eraser:
cv2.circle(self.layer_fore_0, (x, y), radius=self.circle_radius, color=(0,0,0), thickness=-1)
self.layer_fore_1 = np.zeros(shape=self.layer_fore_1.shape, dtype=np.uint8) # 清空layer_fore_1
cv2.circle(self.layer_fore_1, (x, y), radius=self.circle_radius, color=self.eraser_color, thickness=-1)
self.x2, self.y2 = x, y
# 绘制圆形
elif self.mode == 'circle':
cv2.circle(self.layer_fore_1, (x, y), radius=self.circle_radius, color=self.brush_color, thickness=-1)
# 绘制矩形
elif self.mode == 'rectangle':
cv2.rectangle(self.layer_fore_1, (self.x0, self.y0), (self.x1, self.y1), color=(0, 0, 0), thickness=-1) # 用全黑矩形覆盖上一的矩形
cv2.rectangle(self.layer_fore_1, (self.x0, self.y0), (x, y), color=self.brush_color, thickness=-1) # 绘制新的矩形
self.x1, self.y1 = x, y
# 鲁棒性
else:
print("绘图模式错误！")
sys.exit(0)
# （2.2）显示橡皮
elif self.eraser:
self.layer_fore_1 = np.zeros(shape=self.layer_fore_1.shape, dtype=np.uint8) # 清空layer_fore_1
cv2.circle(self.layer_fore_1, (x, y), radius=self.circle_radius, color=self.eraser_color, thickness=-1)
self.x2, self.y2 = x, y
# （2.3）显示圆形画笔
elif self.mode == 'circle': # 未处于绘制状态，且“circle”模式下，需显示circle的效果
cv2.circle(self.layer_fore_1, (self.x2, self.y2), radius=self.circle_radius, color=(0, 0, 0), thickness=-1)
cv2.circle(self.layer_fore_1, (x, y), radius=self.circle_radius, color=self.brush_color, thickness=-1)
self.x2, self.y2 = x, y
# （3）鼠标左键抬起事件——结束绘图状态
elif event == cv2.EVENT_LBUTTONUP:
self.drawing = False
self.click = True
# if self.mode == 'circle':
# 前景图像保存
def saveForeground(self, save_path, mode='raw'):
"""
当使用background时，保存前景图像
:param save_path: 前景图像保存地址
:param mode：模式，'raw'按原前景图存，'black_mask'则按黑白格式存（被画的地方为黑，其余地方为白），'white_mask'相反
:return:
"""
if mode=='raw':
fore = self.layer_fore_0
elif mode=='black_mask':
fore = np.zeros(shape=self.layer_back.shape, dtype=np.uint8) # 初始化为全黑
fore[(self.layer_fore_0[:,:]==np.array([0,0,0])).all(axis=2)] = np.array([255,255,255]) # 未被画的地方设为全白
elif mode=='white_mask':
fore = np.zeros(shape=self.layer_back.shape, dtype=np.uint8) # 初始化为全黑
fore[(self.layer_fore_0[:, :] != np.array([0, 0, 0])).any(axis=2)] = np.array([255, 255, 255]) # 被画的地方设为全白
else:
print("模式错误！")
sys.exit(0)
cv2.imwrite(save_path, fore)
# 将mask作用到图像上
@staticmethod
def useMask(img_mask, img_in, img_out, color_masked=(0, 0, 0)):
"""
:param img_mask：mask图像地址
:param img_in: 原图像目录或地址
:param img_out: 结果图目录或地址
:param color_masked: （B,G,R）待处理图片（img_in），对应到mask图片（img_mask）中颜色为color_masked的部分被mask（即color设为全零）
"""
def useOnOneImg(img_inpath, img_outpath):
img = cv2.imread(img_inpath)
mask = (imgMask[:,:]==np.array(color_masked)).all(axis=2)
img[mask] = np.array([0,0,0])
# cv2.imshow('img', img)
# cv2.waitKey()
cv2.imwrite(img_outpath, img)
# Process
imgMask = cv2.imread(img_mask)
if os.path.isfile(img_in):
useOnOneImg(img_in, img_out)
else:
if not os.path.exists(img_out):
os.makedirs(img_out)
for file in os.listdir(img_in):
if file.endswith('jpg') or file.endswith('.png'):
useOnOneImg(img_inpath=os.path.join(img_in, file),
img_outpath=os.path.join(img_out, file))
# 将img2叠加到img1上，其中仅取img2中颜色为color_list中的部分
@staticmethod
def imgsMerge(img1, img2, color_list):
mask = np.zeros(shape=img1.shape, dtype=bool)
for color in color_list:
curr_mask = (img2[:,:]==np.array(color)).all(axis=2) # shape(w,h)
curr_mask = curr_mask[..., np.newaxis] # shape(w,h,1)
curr_mask = np.repeat(curr_mask, repeats=3, axis=-1) # shape(w,h,3)
mask = mask | curr_mask
np.copyto(dst=img1, src=img2, where=mask)
# 主程序
def main(self):
cv2.namedWindow(self.win_name, cv2.WINDOW_NORMAL)
cv2.setMouseCallback(self.win_name, self.mouseEvent) # 鼠标事件回调函数
while True:
# （1）前景图与背景图的叠加
if self.click: # 每进行一次click（左键按下并松开），则将辅助前景图层（fore_1）绘制的内容复制到前景图层（fore_0）中
mask = (self.layer_fore_1[:, :] == np.array(self.brush_color)).all(axis=2)
self.layer_fore_0[mask] = self.layer_fore_1[mask]
self.click = False
img_tmp = self.layer_back.copy() # 这里需要进行copy，否则两者指向的是同一对象
self.imgsMerge(img_tmp, self.layer_fore_0, color_list=[self.brush_color])
self.imgsMerge(img_tmp, self.layer_fore_1, color_list=[self.brush_color, self.eraser_color])
# np.copyto(dst=img_tmp, src=self.layer_fore_0, where=((self.layer_fore_0[:, :] == np.array(self.brush_color)).all(axis=2)[..., np.newaxis]))
# np.copyto(dst=img_tmp, src=self.layer_fore_1, where=((self.layer_fore_1[:, :] == np.array(self.brush_color)) | (self.layer_fore_1[:, :] == np.array(self.eraser_color))))
cv2.imshow(self.win_name, img_tmp)
if self.show_all_layers:
cv2.namedWindow('layer_fore_0', cv2.WINDOW_NORMAL)
cv2.imshow('layer_fore_0', self.layer_fore_0)
cv2.namedWindow('layer_fore_1', cv2.WINDOW_NORMAL)
cv2.imshow('layer_fore_1', self.layer_fore_1)
# （2）键盘响应
key = cv2.waitKey(1)
if key == ord('m'): # 按下"M"切换绘图模式
print("The mode is changed")
self.switch_fromCircle = True if self.mode=='circle' else False
self.mode = 'circle' if self.mode=='rectangle' else 'rectangle'
elif key == ord('+'):
self.circle_radius += 1
elif key == ord('-'):
self.circle_radius -= 1
if self.mode=='circle'or self.eraser: # 此段解决问题：圆圈缩小的同时，会在layer_fore_1上留下外圈的bug
self.layer_fore_1 = np.zeros(shape=self.layer_fore_1.shape, dtype=np.uint8) # 清空layer_fore_1
color = self.eraser_color if self.eraser else self.brush_color
cv2.circle(self.layer_fore_1, (self.x2, self.y2), radius=self.circle_radius, color=color, thickness=-1)
elif key == ord('e'):
self.switch_fromCircle = True if self.eraser==True else False
self.eraser = not self.eraser
elif key == ord('q'):
print("The windows are destroyed")
break
if self.save_path:
cv2.imwrite(self.save_path, img_tmp)
cv2.destroyAllWindows()
使用示例
painter = Painter(img_size=(1080, 1920, 3),
mode='circle',
background=r'xxx.jpg',
circle_radius=50,
save_path=None,
color=(0,0,255),
show_all_layers=False)
painter.main()
# painter.saveForeground(save_path='fore.jpg',
# mode='black_mask')
# painter.useMask(img_mask=r'fore.jpg',
# img_in=r'xxx\image',
# img_out=r'xxx\image_masked')
效果示例
