Python Telegram Bot library throws encoding error when uploading image files

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1

I’m working with a Telegram bot using Python 2.7 and running into character encoding issues when sending pictures. When I try to upload an image file, I get a UnicodeDecodeError.

Here’s my current approach for sending photos:

bot.send_photo(chat_id=user_chat.id, photo=open(picture_file.full_path, 'rb'))

The picture_file.full_path contains the complete file system path to a JPEG image. However, this throws an encoding exception:

UnicodeDecodeError: 'ascii' codec can't decode byte 0xff in position 0: ordinal not in range(128)

I also attempted to handle the encoding manually:

with io.open(picture_file.full_path, 'r', encoding='utf8') as img:
    bot.send_photo(chat_id=user_chat.id, photo=img.read())

But this creates a different type of encoding problem. The error seems to happen inside the library when it tries to process the binary image data as text. Has anyone found a working solution for uploading photos without these encoding issues?

2

try sending the file obj directly instead of reading it. somethin like with open(picture_file.full_path, 'rb') as f: bot.send_photo(chat_id=user_chat.id, photo=f) worked for me with similar issues in py2.7

3

Had the exact same issue last year migrating an old project. Python 2.7 chokes on unicode file paths - even in binary mode, it processes the path string and hits encoding problems. Fixed it by encoding the path first: file_path = picture_file.full_path.encode('utf-8') then bot.send_photo(chat_id=user_chat.id, photo=open(file_path, 'rb')). Also check your filesystem locale - sometimes the OS returns paths in weird encodings. If you’re still stuck, try absolute paths and avoid folders with special characters.

4

This happens because you’re mixing text and binary modes with image data. Don’t use io.open with text mode for images - that’s definitely wrong since images are binary files. Your first method should work, but the encoding error means the library might be trying to process the file path string instead of the actual binary content. I’ve hit this same issue in Python 2.7. Fix it by passing the file object directly and keeping it open - don’t close it right away. Alex_Brave’s context manager approach works well, but sometimes you need that file handle to stay open through the entire send operation. Also check if your file path has any non-ASCII characters. Python 2.7’s string handling can choke on those before it even gets to the file content.