Check if file is image python

Update

I also implemented the following solution in my Python script here on GitHub.

I also verified that damaged files [jpg] frequently are not 'broken' images i.e, a damaged picture file sometimes remains a legit picture file, the original image is lost or altered but you are still able to load it with no errors. But, file truncation cause always errors.

End Update

You can use Python Pillow[PIL] module, with most image formats, to check if a file is a valid and intact image file.

In the case you aim at detecting also broken images, @Nadia Alramli correctly suggests the im.verify[] method, but this does not detect all the possible image defects, e.g., im.verify does not detect truncated images [that most viewers often load with a greyed area].

Pillow is able to detect these type of defects too, but you have to apply image manipulation or image decode/recode in or to trigger the check. Finally I suggest to use this code:

from PIL import Image

try:
  im = Image.load[filename]
  im.verify[] #I perform also verify, don't know if he sees other types o defects
  im.close[] #reload is necessary in my case
  im = Image.load[filename] 
  im.transpose[Image.FLIP_LEFT_RIGHT]
  im.close[]
except: 
  #manage excetions here

In case of image defects this code will raise an exception. Please consider that im.verify is about 100 times faster than performing the image manipulation [and I think that flip is one of the cheaper transformations]. With this code you are going to verify a set of images at about 10 MBytes/sec with standard Pillow or 40 MBytes/sec with Pillow-SIMD module [modern 2.5Ghz x86_64 CPU].

For the other formats xcf,.. you can use Imagemagick wrapper Wand, the code is as follows: Check the Wand documentation: here, to installation: here

im = wand.image.Image[filename=filename]
temp = im.flip;
im.close[]

But, from my experiments Wand does not detect truncated images, I think it loads lacking parts as greyed area without prompting.

I red that Imagemagick has an external command identify that could make the job, but I have not found a way to invoke that function programmatically and I have not tested this route.

I suggest to always perform a preliminary check, check the filesize to not be zero [or very small], is a very cheap idea:

import os

statfile = os.stat[filename]
filesize = statfile.st_size
if filesize == 0:
  #manage here the 'faulty image' case

Python has many modules in its standard library. One that is often overlooked is imghdr which lets you identify what image type that is contained in a file, byte stream or path-like object.

The imghdr can recognize the following image types:

• rgb
• gif
• pbm
• pgm
• ppm
• tiff
• rast
• xbm
• jpeg / jpg
• bmp
• png
• webp
• exr

Here is how you would use it imghdr to detect the image type of a file:

>>> import imghdr
>>> path = 'python.jpg'
>>> imghdr.what[path]
'jpeg'
>>> path = 'python.png'
>>> imghdr.what[path]
'png'

All you need to do is pass a path to imghdr.what[path] and it will tell you what it thinks the image type is.

An alternative method to use would be to use the Pillow package which you can install with pip if you don't already have it.

Here is how you can use Pillow:

>>> from PIL import Image
>>> img = Image.open['/home/mdriscoll/Pictures/all_python.jpg']
>>> img.format
'JPEG'

This method is almost as easy as using imghdr. In this case, you need to create an Image object and then call its format attribute. Pillow supports more image types than imghdr, but the documentation doesn't really say if the format attribute will work for all those image types.

Anyway, I hope this helps you in identifying the image type of your files.

from PIL import Image
try:
    im=Image.open[filename]
    # do stuff
except IOError:
    # filename not an image file

>>> import imghdr
>>> imghdr.what['/tmp/bass']
'gif'

filename.lower[].endswith[['.png', '.jpg', '.jpeg', '.tiff', '.bmp', '.gif']]

import filetype

filename = "/path/to/file.jpg"

if filetype.is_image[filename]:
    print[f"{filename} is a valid image..."]
elif filetype.is_video[filename]:
    print[f"{filename} is a valid video..."]