Python pillow模块出现cannot write mode RGBA as JPEG问题的解决方法

本文主要是介绍Python pillow模块出现cannot write mode RGBA as JPEG问题的解决方法，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

背景

最近在解决一个问题:如何自动截取Excel里面的范围为图片并发送.最后使用pywin32模块解决了,但是在发送的时候,个别部署电脑会出现一些问题,就是下面这种报错

cannot write mode RGBA as JPEG

后来发现有些电脑在使用VBA的CopyPicture方法会默认为PNG格式,有些默认是JPG格式,奇奇怪怪的

问题

出现问题的是下面这一段,为了更好理解,我将上下文放了出来

img = ImageGrab.grabclipboard()
imgpath = os.path.join(os.path.dirname(__file__),'{imgname}.{fmt}'.format(imgname=time.strftime('%Y%m%d%H%M%S'),fmt=fmt))
img.save(imgpath) # 这一句有报错

报错完整信息如下

Traceback (most recent call last):File "C:\Users\Administrator\AppData\Local\Programs\Python\Python39\lib\site-packages\PIL\JpegImagePlugin.py", line 611, in _saverawmode = RAWMODE[im.mode]
KeyError: 'RGBA'The above exception was the direct cause of the following exception:Traceback (most recent call last):File "D:\onedrive\doc\for_share\Python_eco\python\work_wechat_amiba.py", line 22, in <module>amiba()File "D:\onedrive\doc\for_share\Python_eco\python\work_wechat_amiba.py", line 14, in amibaimg = excel.savePic(['post'],'jpg')File "D:\onedrive\doc\for_share\Python_eco\python\Udfs\cls_excel.py", line 80, in savePicimg.save(self._picPath)File "C:\Users\Administrator\AppData\Local\Programs\Python\Python39\lib\site-packages\PIL\Image.py", line 2151, in savesave_handler(self, fp, filename)File "C:\Users\Administrator\AppData\Local\Programs\Python\Python39\lib\site-packages\PIL\JpegImagePlugin.py", line 613, in _saveraise OSError(f"cannot write mode {im.mode} as JPEG") from e
OSError: cannot write mode RGBA as JPEG

方案

解决方案也是非常简单,加一句转换就可以了

img = ImageGrab.grabclipboard()
imgpath = os.path.join(os.path.dirname(__file__),'{imgname}.{fmt}'.format(imgname=time.strftime('%Y%m%d%H%M%S'),fmt=fmt))
img.convert('RGB')	# 这一句
img.save(imgpath)