cv2.imwrite(os.path.join(save_pic_path, auged_pic_path), auged_img) cv2.error: OpenCV(4.7.0) D:\a\opencv-python\opencv-python\opencv\modules\imgcodecs\src\loadsave.cpp:783: error: (-215:Assertion failed) !_img.empty() in function 'cv::imwrite'

根据错误信息，`cv2.imwrite`函数在保存图像时出现了断言错误。具体错误信息是：图像为空（`_img.empty()`）。

这个错误通常发生在尝试保存一个空的图像时。请确保你传递给`cv2.imwrite`函数的图像是有效的，且不为空。

你可以检查一下图像的路径是否正确，以及图像是否成功加载和处理。如果图像加载成功，并且在进行处理后，还可以检查一下图像的尺寸是否正确。

另外，如果你能提供更多的代码和错误堆栈信息，我可以给出更具体的解决方案。

相关问题

import os import numpy as np import nibabel as nib import imageio import cv2 def read_niifile(niifilepath): # 读取niifile文件 img = nib.load(niifilepath) # 提取niifile文件 img_fdata = img.get_fdata(dtype='float32') return img_fdata def save_fig(niifilepath, savepath, num, name): # 保存为图片 name = name.split('-')[1] filepath_seg = niifilepath + "segmentation\" + "segmentation-" + name filepath_vol = niifilepath + "volume\" + "volume-" + name savepath_seg = savepath + "segmentation\" savepath_vol = savepath + "volume\" if not os.path.exists(savepath_seg): os.makedirs(savepath_seg) if not os.path.exists(savepath_vol): os.makedirs(savepath_vol) fdata_vol = read_niifile(filepath_vol) fdata_seg = read_niifile(filepath_seg) (x, y, z) = fdata_seg.shape total = x * y for k in range(z): silce_seg = fdata_seg[:, :, k] # 三个位置表示三个不同角度的切片 if silce_seg.max() == 0: continue else: silce_seg = (silce_seg - silce_seg.min()) / (silce_seg.max() - silce_seg.min()) * 255 silce_seg = cv2.threshold(silce_seg, 1, 255, cv2.THRESH_BINARY)[1] if (np.sum(silce_seg == 255) / total) > 0.015: silce_vol = fdata_vol[:, :, k] silce_vol = (silce_vol - silce_vol.min()) / (silce_vol.max() - silce_vol.min()) * 255 imageio.imwrite(os.path.join(savepath_seg, '{}.png'.format(num)), silce_seg) imageio.imwrite(os.path.join(savepath_vol, '{}.png'.format(num)), silce_vol) num += 1 # 将切片信息保存为png格式 return num if name == 'main': path = r"C:\Users\Administrator\Desktop\LiTS2017" savepath = r"C:\Users\Administrator\Desktop\2D-LiTS2017" filenames = os.listdir(path + "segmentation") num = 0 for filename in filenames: num = save_fig(path, savepath, num, filename) 替换掉代码中的cv2模块，实现相同功能

可以使用PIL库替换掉cv2模块，实现相同的功能。具体替换方法如下：

1.导入PIL库

from PIL import Image

2.将cv2.threshold替换为PIL.ImageOps.autocontrast

silce_seg = (silce_seg - silce_seg.min()) / (silce_seg.max() - silce_seg.min()) * 255
silce_seg = Image.fromarray(silce_seg.astype('uint8'))
silce_seg = ImageOps.autocontrast(silce_seg, cutoff=1)
silce_seg = np.array(silce_seg)

3.将cv2.imwrite替换为PIL.Image.save

imageio.imwrite(os.path.join(savepath_seg, '{}.png'.format(num)), silce_seg)
imageio.imwrite(os.path.join(savepath_vol, '{}.png'.format(num)), silce_vol)

替换后的代码如下：

import os 
import numpy as np 
import nibabel as nib 
import imageio 
from PIL import Image, ImageOps

def read_niifile(niifilepath):  
    # 读取niifile文件     
    img = nib.load(niifilepath)  
    # 提取niifile文件     
    img_fdata = img.get_fdata(dtype='float32')     
    return img_fdata   

def save_fig(niifilepath, savepath, num, name):  
    # 保存为图片     
    name = name.split('-')[1]     
    filepath_seg = niifilepath + "segmentation/" + "segmentation-" + name     
    filepath_vol = niifilepath + "volume/" + "volume-" + name     
    savepath_seg = savepath + "segmentation/"     
    savepath_vol = savepath + "volume/"      

    if not os.path.exists(savepath_seg):         
        os.makedirs(savepath_seg)     
    if not os.path.exists(savepath_vol):         
        os.makedirs(savepath_vol)      

    fdata_vol = read_niifile(filepath_vol)     
    fdata_seg = read_niifile(filepath_seg)     
    (x, y, z) = fdata_seg.shape     
    total = x * y      

    for k in range(z):         
        silce_seg = fdata_seg[:, :, k]  # 三个位置表示三个不同角度的切片         
        if silce_seg.max() == 0:             
            continue         
        else:             
            silce_seg = (silce_seg - silce_seg.min()) / (silce_seg.max() - silce_seg.min()) * 255             
            silce_seg = Image.fromarray(silce_seg.astype('uint8'))
            silce_seg = ImageOps.autocontrast(silce_seg, cutoff=1)
            silce_seg = np.array(silce_seg)

            if (np.sum(silce_seg == 255) / total) > 0.015:                 
                silce_vol = fdata_vol[:, :, k]                 
                silce_vol = (silce_vol - silce_vol.min()) / (silce_vol.max() - silce_vol.min()) * 255                  

                imageio.imwrite(os.path.join(savepath_seg, '{}.png'.format(num)), silce_seg)                 
                imageio.imwrite(os.path.join(savepath_vol, '{}.png'.format(num)), silce_vol)                 
                num += 1         
        # 将切片信息保存为png格式     
    return num   

if __name__ == '__main__':      
    path = r"C:\Users\Administrator\Desktop\LiTS2017"     
    savepath = r"C:\Users\Administrator\Desktop\2D-LiTS2017"     
    filenames = os.listdir(path + "segmentation")     
    num = 0     
    for filename in filenames:         
        num = save_fig(path, savepath, num, filename)

替换掉此代码里的import cv2模块，import os import numpy as np import nibabel as nib import imageio import cv2 def read_niifile(niifilepath): # 读取niifile文件 img = nib.load(niifilepath) # 提取niifile文件 img_fdata = img.get_fdata(dtype='float32') return img_fdata def save_fig(niifilepath, savepath, num, name): # 保存为图片 name = name.split('-')[1] filepath_seg = niifilepath + "segmentation\\" + "segmentation-" + name filepath_vol = niifilepath + "volume\\" + "volume-" +name savepath_seg = savepath + "segmentation\\" savepath_vol = savepath + "volume\\" if not os.path.exists(savepath_seg): os.makedirs(savepath_seg) if not os.path.exists(savepath_vol): os.makedirs(savepath_vol) fdata_vol = read_niifile(filepath_vol) fdata_seg = read_niifile(filepath_seg) (x, y, z) = fdata_seg.shape total = x * y for k in range(z): silce_seg = fdata_seg[:, :, k] # 三个位置表示三个不同角度的切片 if silce_seg.max() == 0: continue else: silce_seg = (silce_seg-silce_seg.min())/(silce_seg.max() - silce_seg.min())*255 silce_seg = cv2.threshold(silce_seg, 1, 255, cv2.THRESH_BINARY)[1] if (np.sum(silce_seg == 255) / total) > 0.015: silce_vol = fdata_vol[:, :, k] silce_vol = (silce_vol - silce_vol.min()) / (silce_vol.max() - silce_vol.min()) * 255 imageio.imwrite(os.path.join(savepath_seg, '{}.png'.format(num)), silce_seg) imageio.imwrite(os.path.join(savepath_vol, '{}.png'.format(num)), silce_vol) num += 1 # 将切片信息保存为png格式 return num if __name__ == '__main__': path= 'E:\\dataset\\LiTS17\\' savepath = 'E:\\dataset\\LiTS17\\2d\\' filenames = os.listdir(path + "segmentation") num = 0 for filename in filenames: num = save_fig(path, savepath, num, filename)

替换掉此代码里的import cv2模块，可以使用Pillow库中的Image模块进行替换。具体实现方式如下：

import os 
import numpy as np 
import nibabel as nib 
import imageio 
from PIL import Image

def read_niifile(niifilepath):  # 读取niifile文件
    img = nib.load(niifilepath)  # 提取niifile文件
    img_fdata = img.get_fdata(dtype='float32')
    return img_fdata

def save_fig(niifilepath, savepath, num, name):  # 保存为图片
    name = name.split('-')[1]
    filepath_seg = niifilepath + "segmentation\\"  + "segmentation-" + name
    filepath_vol = niifilepath + "volume\\" + "volume-" +name
    savepath_seg = savepath + "segmentation\\"
    savepath_vol = savepath + "volume\\"
    
    if not os.path.exists(savepath_seg):
        os.makedirs(savepath_seg)
    if not os.path.exists(savepath_vol):
        os.makedirs(savepath_vol)
    
    fdata_vol = read_niifile(filepath_vol)
    fdata_seg = read_niifile(filepath_seg)
    (x, y, z) = fdata_seg.shape
    total = x * y
    
    for k in range(z):
        silce_seg = fdata_seg[:, :, k]
        if silce_seg.max() == 0:
            continue
        else:
            silce_seg = (silce_seg-silce_seg.min())/(silce_seg.max() - silce_seg.min())*255
            silce_seg  = cv2.threshold(silce_seg, 1, 255, cv2.THRESH_BINARY)[1]
            
            if  (np.sum(silce_seg == 255) / total) > 0.015:
                silce_vol = fdata_vol[:, :, k]
                silce_vol = (silce_vol - silce_vol.min()) / (silce_vol.max() - silce_vol.min()) * 255
                
                # 保存为png格式
                Image.fromarray(silce_seg.astype(np.uint8)).save(os.path.join(savepath_seg, '{}.png'.format(num)))
                Image.fromarray(silce_vol.astype(np.uint8)).save(os.path.join(savepath_vol, '{}.png'.format(num)))
                num += 1
    
    return num

if __name__ == '__main__':
    path= 'E:\\dataset\\LiTS17\\'
    savepath = 'E:\\dataset\\LiTS17\\2d\\'
    filenames = os.listdir(path + "segmentation")
    num = 0
    for filename in filenames:
        num = save_fig(path, savepath, num, filename)