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how to read an image with opencv using path variable in Python

So I have a variable that holds the image path as a string. but I get the below error while trying to read the image using the path variable. The path variable is coming from another function that calls this code.
Error:
can't open/read file: check file path/integrity
My code:
path = "D://dev//py_scripts//SS1.jpg"
image=cv2.imread(path)
Tried several solutions but ended up with same error.

Double forward slashes make the path invalid.
Use single forward slashes. That is commonly tolerated on Windows, which natively wants backslashes.
Double backslashes are only what you see. They're actually single backslashes in the path/string, but the string syntax requires escaping backslashes (and other stuff) by a preceding backslash, so that's why one has to use double backslashes in most string literals...
Python has "r-strings" ("raw" strings). In a raw string, even backslashes are taken literally, and nothing is escapable (a matching quote character ends the string, always).
"D:/dev/py_scripts/SS1.jpg"
r"D:\dev\py_scripts\SS1.jpg"
"D:\\dev\\py_scripts\\SS1.jpg"

import cv2
path1= "SS1.jpg"
#sometimes doesnt work depends on the compiler. If its on sub folder #py_scripts\SS1.jpg
or
path2= "d:\dev\py_scripts\SS1.jpg"
image = cv2.imread(path2)
If you want to use path1 method, and set it to work 100%
import os
os.chdir(os.path.dirname(os.path.abspath(__file__)))

I would suggest changing the format of the path as follows:
import cv2
#Several options
path = r"D:\dev\py_scripts\SS1.jpg"
path = r"D:/dev/py_scripts/SS1.jpg"
path = "D:/dev/py_scripts/SS1.jpg"
image=cv2.imread(path)
But based on the error you are getting, you need to check the format of the image and its integrity, as the error says. That means you must be able to open the image without issues on an editor like Windows Photos to check if the file is not corrupted.

Does os.path.sep affect the tarfile module?

Is the path separator employed inside a Python tarfile.TarFile object a '/' regardless of platform, or is it a backslash on Windows?
I basically never touch Windows, but I would kind of like the code I'm writing to be compatible with it, if it can be. Unfortunately I have no Windows host on which to test.

A quick test tells me that a (forward) slash is always used.
In fact, the tar format stores the full path of each file as a single string, using slashes (try looking at a hex dump), and python just reads that full path without any modification. Likewise, at extraction time python hard-replaces slashes with the local separator (see TarFile._extract_member).
... which makes me think that there are surely some nonconformant implementations of tar for Windows that create tarfiles with backslashs as separators!?

os.listdir can't see my directory

I am working on a python script that installs an 802.1x certificate on a Windows 8.1 machine. This script works fine on Windows 8 and Windows XP (haven't tried it on other machines).
I have isolated the issue. It has to do with clearing out the folder
"C:\Windows\system32\config\systemprofile\AppData\LocalLow\Microsoft\CryptURLCache\Content"
The problem is that I am using the module os and the command listdir on this folder to delete each file in it. However, listdir errors, saying the folder does not exist, when it does indeed exist.
The issue seems to be that os.listdir cannot see the LocalLow folder. If I make a two line script:
import os
os.listdir("C:\Windows\System32\config\systemprofile\AppData")
It shows the following result:
['Local', 'Roaming']
As you can see, LocalLow is missing.
I thought it might be a permissions issue, but I am having serious trouble figuring out what a next step might be. I am running the process as an administrator from the command line, and it simply doesn't see the folder.
Thanks in advance!
Edit: changing the string to r"C:\Windows\System32\config\systemprofile\AppData", "C:\Windows\System32\config\systemprofile\AppData", or C:/Windows/System32/config/systemprofile/AppData" all produce identical results
Edit: Another unusual wrinkle in this issue: If I manually create a new directory in that location I am unable to see it through os.listdir either. In addition, I cannot browse to the LocalLow or my New Folder through the "Save As.." command in Notepad++
I'm starting to think this is a bug in Windows 8.1 preview.

I encountered this issue recently.
I found it's caused by Windows file system redirector
and you can check out following python snippet
import ctypes
class disable_file_system_redirection:
_disable = ctypes.windll.kernel32.Wow64DisableWow64FsRedirection
_revert = ctypes.windll.kernel32.Wow64RevertWow64FsRedirection
def __enter__(self):
self.old_value = ctypes.c_long()
self.success = self._disable(ctypes.byref(self.old_value))
def __exit__(self, type, value, traceback):
if self.success:
self._revert(self.old_value)
#Example usage
import os
path = 'C:\\Windows\\System32\\config\\systemprofile\\AppData'
print os.listdir(path)
with disable_file_system_redirection():
print os.listdir(path)
print os.listdir(path)
ref : http://code.activestate.com/recipes/578035-disable-file-system-redirector/

You must have escape sequences in your path. You should use a raw string for file/directory paths:
# By putting the 'r' at the start, I make this string a raw string
# Raw strings do not process escape sequences
r"C:\path\to\file"
or put the slashes the other way:
"C:/path/to/file"
or escape the slashes:
# You probably won't want this method because it makes your paths huge
# I just listed it because it *does* work
"C:\\path\\to\\file"

I'm curious as to how you are able to list the contents with those two lines. You are using escape sequences \W, \S, \c, \s, \A in your code. Try escaping the back slash like this:
import os
os.listdir('C:\\Windows\\System32\\config\\systemprofile\\AppData')

Cannot read in files

I have a small problem with reading in my file. My code:
import csv as csv
import numpy
with open("train_data.csv","rb") as training:
csv_file_object = csv.reader(training)
header = csv_file_object.next()
data = []
for row in csv_file_object:
data.append(row)
data = numpy.array(data)
I get the error no such file "train_data.csv", so I know the problem lies with the location. But whenever I specify the pad like this: open("C:\Desktop...etc) it doesn't work either. What am I doing wrong?

If you give the full file path, your script should work. Since it is not, it must be that you have escape characters in your path. To fix this, use a raw-string to specify the file path:
# Put an 'r' at the start of the string to make it a raw-string.
with open(r"C:\path\to\file\train_data.csv","rb") as training:
Raw strings do not process escape characters.
Also, just a technical fact, not giving the full file path causes Python to look for the file in the directory that the script is launched from. If it is not there, an error is thrown.

When you use open() and Windows you need to deal with the backslashes properly.
Option 1.) Use the raw string, this will be the string prefixed with an r.
open(r'C:\Users\Me\Desktop\train_data.csv')
Option 2.) Escape the backslashes
open('C:\\Users\\Me\\Desktop\\train_data.csv')
Option 3.) Use forward slashes
open('C:/Users/Me/Desktop/train_data.csv')
As for finding the file you are using, if you just do open('train_data.csv') it is looking in the directory you are running the python script from. So, if you are running it from C:\Users\Me\Desktop\, your train_data.csv needs to be on the desktop as well.

How do I use '~' (tilde) in the context of paths?

To fix a problem in code for work, I was told to "use a path relative to ~". What does ~ mean in a file path? How can I make a path that is relative to ~, and use that path to open files in Python?

it is your $HOME var in UNIX, which usually is /home/username.
"Your home" meaning the home of the user who's executing a command like cd ~/MyDocuments/ is cd /home/user_executing_cd_commnd/MyDocuments

Unless you're writing a shell script or using some other language that knows to substitute the value of $HOME for ~, tildes in file paths have no special meaning and will be treated as any other non-special character.
If you are writing a shell script, shells don't interpret tildes unless they occur as the first character in an argument. In other words, ~/file will become /path/to/users/home/directory/file, but ./~/file will be interpreted literally (i.e., "a file called file in a subdirectory of . called ~").
Used in URLs, interpretation of the tilde as a shorthand for a user's home directory (e.g., http://www.foo.org/~bob) is a convention borrowed from Unix. Implementation is entirely server-specific, so you'd need to check the documentation for your web server to see if it has any special meaning.

If you are using pathlib for filenames then you can use on both Windows and Linux (I came here for a windows answer):
from pathlib import Path
p = Path('~').expanduser()
print(p)