python去噪笔记

╰+攻爆jí腚メ 2022-01-09 15:34 311阅读 0赞

import matplotlib.pyplot as plt
    import sys, os
    from PIL import Image, ImageDraw
    
    
    # 二值判断,如果确认是噪声,用改点的上面一个点的灰度进行替换
    # 该函数也可以改成RGB判断的,具体看需求如何
    def getPixel(image, x, y, G, N):
        L = image.getpixel((x, y))
        if L > G:
            L = True
        else:
            L = False
    
        nearDots = 0
        if L == (image.getpixel((x - 1, y - 1)) > G):
            nearDots += 1
        if L == (image.getpixel((x - 1, y)) > G):
            nearDots += 1
        if L == (image.getpixel((x - 1, y + 1)) > G):
            nearDots += 1
        if L == (image.getpixel((x, y - 1)) > G):
            nearDots += 1
        if L == (image.getpixel((x, y + 1)) > G):
            nearDots += 1
        if L == (image.getpixel((x + 1, y - 1)) > G):
            nearDots += 1
        if L == (image.getpixel((x + 1, y)) > G):
            nearDots += 1
        if L == (image.getpixel((x + 1, y + 1)) > G):
            nearDots += 1
    
        if nearDots < N:
            return image.getpixel((x, y - 1))
        else:
            return None
    
    
    # 降噪
    # 根据一个点A的RGB值，与周围的8个点的RBG值比较，设定一个值N（0 <N <8），当A的RGB值与周围8个点的RGB相等数小于N时，此点为噪点
    # G: Integer 图像二值化阀值
    # N: Integer 降噪率 0 <N <8
    # Z: Integer 降噪次数
    # 输出
    #  0：降噪成功
    #  1：降噪失败
    def clearNoise(image, G, N, Z):
        draw = ImageDraw.Draw(image)
    
        for i in range(0, Z):
            for x in range(1, image.size[0] - 1):
                for y in range(1, image.size[1] - 1):
                    color = getPixel(image, x, y, G, N)
                    if color != None:
                        draw.point((x, y), color)
    
    
    # 测试代码
    def main():
        # 打开图片
        img = Image.open(r"F:\主题一：遥感图像场景分类\val\val\冰岛\ice-land_00013.jpg")
    
        # 将图片转换成灰度图片
        image = img.convert("L")
    
        # 去噪,G = 50,N = 3,Z = 8
        clearNoise(image, 50, 3, 8)
        plt.subplot(121), plt.imshow(img)
        plt.subplot(122), plt.imshow(image)
        plt.show()
        # 保存图片
        # image.save(r'F:\3.jpg')
    
    
    if __name__ == '__main__':
        main()

#### 结果 ####

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4NDEwNDI4_size_16_color_FFFFFF_t_70]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4NDEwNDI4_size_16_color_FFFFFF_t_70 1]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4NDEwNDI4_size_16_color_FFFFFF_t_70]: /images/20220109/f0e7366872cc448ebd47ea281ba5dd2a.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4NDEwNDI4_size_16_color_FFFFFF_t_70 1]: /images/20220109/7bbb9cb4e2904876be1ede70a8237134.png