我正在尝试为 Discord 机器人实现一个系统,该系统可以动态修改图像并将其发送给机器人用户。为此,我决定使用 Pillow (PIL) 库,因为它对于我的目的来说似乎简单明了。
这是我的工作代码的示例。它加载一个示例图像,作为测试修改,在其上绘制两条对角线,并将图像输出为 Discord 消息:
# Open source image
img = Image.open('example_image.png')
# Modify image
draw = ImageDraw.Draw(img)
draw.line((0, 0) + img.size, fill=128)
draw.line((0, img.size[1], img.size[0], 0), fill=128)
# Save to disk and create discord file object
img.save('tmp.png', format='PNG')
file = discord.File(open('tmp.png', 'rb'))
# Send picture as message
await message.channel.send("Test", file=file)
这会导致我的机器人发出以下消息:
这有效;但是,我想省略将图像保存到硬盘并再次加载的步骤,因为这似乎效率很低且不必要。经过一番谷歌搜索后,我发现了以下解决方案;但是,它似乎不起作用:
# Save to disk and create discord file object
# img.save('tmp.png', format='PNG')
# file = discord.File(open('tmp.png', 'rb'))
# Save to memory and create discord file object
arr = io.BytesIO()
img.save(arr, format='PNG')
file = discord.File(open(arr.getvalue(), 'rb'))
这会导致以下错误消息:
Traceback (most recent call last):
File "C:\Users\<username>\AppData\Local\Programs\Python\Python38-32\lib\site-packages\discord\client.py", line 270, in _run_event
await coro(*args, **kwargs)
File "example_bot.py", line 48, in on_message
file = discord.File(open(arr.getvalue(), 'rb'))
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x89 in position 0: invalid start byte