looping over images in a directory - linux

Question

I have images in the same directory with a python file, i am trying to loop over the images and convert them into base64 but am getting this error.
Am using Ubuntu 14.0.4
Traceback (most recent call last):
File "convert_to_base64.py", line 33, in <module>
print(main())
File "convert_to_base64.py", line 26, in main
convert_to_base64()
File "convert_to_base64.py", line 19, in convert_to_base64
with open("*.jpg", "rb") as f:
IOError: [Errno 2] No such file or directory: '*.jpg'
Here is my python code
# -*- coding: utf-8 -*-
import os
import sys
import xlrd
import base64
import urllib
from datetime import datetime
reload(sys) # to re-enable sys.setdefaultencoding()
sys.setdefaultencoding('utf-8')
def convert_to_base64():
"""
Read all jpg images in a folder,
and print them in base64
"""
with open("*.jpg", "rb") as f:
data = base64.b64decode(f.read())
print data
def main():
start_datetime = datetime.now()
convert_to_base64()
end_datetime = datetime.now()
print '------------------------------------------------------'
print 'Script started : {}'.format(start_datetime)
print 'Script finished: {}'.format(end_datetime)
if __name__ == '__main__':
print(main())
print('Done')
someone help me figure out what am doing wrong.
Thanks

Answer 1

This is how I looped for images in a directory:
import os
pictures = []
for file in os.listdir("pictures"):
if file[-3:].lower() in ["png"]:
pictures.append(file)
Please refer to Python documentation https://docs.python.org/2/tutorial/inputoutput.html for more info on open() function:
open() returns a file object, and is most commonly used with two arguments: open(filename, mode).