How can I modify an image file with Python using no imports?

Question

I know how to modify texts files (format.txt) normally, but, when I try to do the same thing with images... I don't get...

Well, I know that open and write the image in binary mode (rb and wb) are necessary, however, I can't to override the image bytes and save them to, for example, get the same image but with its pixels changed.

Please, I searched in web, but the unique thing I found was Pillow (damn, I am stupid, cos dunno how to download it on my pc [pip install Pillow doesn't work in my computer by cmd]), help me '-'.

Oh, abridgeding, I would like to change the bytes of an image and save them in order to get the same image with different colors and qualitys.

Answer 1

You probably also want to have a look at the sk-image library. For installation instructions pls search the web.

Answer 2

To install pillow from cmd under python 3, try :
py -3 -m pip install pillow

The image you can easily modify are bmp files, because there is no compression.
While reading a file, use seek function (search on Google).

Hope that helps!