We're back after a server migration that caused effbot.org to fall over a bit harder than expected. Expect some glitches.

The imghdr module

This module identifies different image file formats. The current version identifies bmp, gif, jpeg, pbm, pgm, png, ppm, rast (Sun raster), rgb (SGI), tiff, and xbm images.

Example: Using the imghdr module
# File: imghdr-example-1.py

import imghdr

result = imghdr.what("samples/sample.jpg")

if result:
    print "file format:", result
    print "cannot identify file"

file format: jpeg
import Image

im = Image.open("samples/sample.jpg")
print im.format, im.mode, im.size