Check if a file type is a media file?

There is another method that is based not on the file extension but on the file contents using the media type library pypi.org/project/python-libmagic:

Here is the sample code for this library:

import magic

magic = magic.Magic()
mimestart = magic.from_file("test.mp3").split('/')[0]

if mimestart in ['audio', 'video', 'image']:
    print("media types")

NOTE: for using this code sample you need to install python-libmagic using pip.

For this purpose you need to get internet media type for file, split it by / character and check if it starts with audio,video,image.

Here is a sample code:

import mimetypes
mimetypes.init()

mimestart = mimetypes.guess_type("test.mp3")[0]

if mimestart != None:
    mimestart = mimestart.split('/')[0]

    if mimestart in ['audio', 'video', 'image']:
        print("media types")

NOTE: This method assume the file type by its extension and don't open the actual file, it is based only on the file extension.

Creating a module

If you want to create a module that checks if the file is a media file you need to call the init function at the start of the module.

Here is an example of how to create the module:

ismediafile.py

import mimetypes
mimetypes.init()

def isMediaFile(fileName):
    mimestart = mimetypes.guess_type(fileName)[0]

    if mimestart != None:
        mimestart = mimestart.split('/')[0]

        if mimestart in ['audio', 'video', 'image']:
            return True
    
    return False

and there how to use it:

main.py

from ismediafile import isMediaFile

if __name__ == "__main__":
    if isMediaFile("test.mp3"):
        print("Media file")
    else:
        print("not media file")