Develop Reference

issues running a face_recogition file using editors and cmd

When I run the code below in jupyter, it is excellent, I get the results I want.
real = fr.load_image_file("image.jpg")
unknown = fr.load_image_file("image2.jpg")
# encodings
real_encoding = fr.face_encodings(real)[0]
unk = fr.face_encodings(unknown)[0]
result = fr.compare_faces([real_encoding], unk)
print(result)
but when I copy and paste the same code to an editor(atom the one I am using), and then run it using command prompt, I get an error as shown below
Traceback (most recent call last):
File "face_recognizer.py", line 13, in <module>
real_encoding = fr.face_encodings(real)[0]
IndexError: list index out of range
I activated the environment in which I was running the cmd.
Can someone advise me where I maybe going wrong?

There was no face captured in the photo.
That is why it throws an exception.

How to fix 'IndexError: index out of range'

I have built a simple app with Blynk. Unfortunately, I regularly get the error:
Traceback (most recent call last):
File "/home/pi/Desktop/Blynk/blynktest2.py", line 12, in <module>
blynk.run()
File "/home/pi/.local/lib/python3.7/site-packages/BlynkLib.py", line 252, in run
self.process(data)
File "/home/pi/.local/lib/python3.7/site-packages/BlynkLib.py", line 213, in process
self.emit("int_"+args[1], args[2:])
IndexError: list index out of range
Even if I take out all code on my hardware and end up with the following code, the error comes up:
import BlynkLib
BLYNK_AUTH = 'MY_AUTH_IS_NORMALLY_HERE'
# initialize blynk
blynk = BlynkLib.Blynk(BLYNK_AUTH)
while True:
blynk.run()
I do not know exactly what causes the error, however, I noticed that the error occurs
when the Blynk app is moved to the background
when the screen of the mobile phone turns black
the eror does not occur when normal disconnecting in the Blynk app via the stop button in the top right, and also not if reconnecting then

This is one random issue which keeps happening. Try recreating the project by removing all the controllers or create a new project and update the authentication code in your code.

Python can't import WMI under special circumstance

I've created a standalone exe Windows service written in Python and built with pyInstaller. When I try to import wmi, an exception is thrown.
What's really baffling is that I can do it without a problem if running the code in a foreground exe, or a foreground python script, or a python script running as a background service via pythonservice.exe!
Why does it fail under this special circumstance of running as a service exe?
import wmi
Produces this error for me:
com_error: (-2147221020, 'Invalid syntax', None, None)
Here's the traceback:
Traceback (most recent call last):
File "<string>", line 43, in onRequest
File "C:\XXX\XXX\XXX.pyz", line 98, in XXX
File "C:\XXX\XXX\XXX.pyz", line 31, in XXX
File "C:\XXX\XXX\XXX.pyz", line 24, in XXX
File "C:\XXX\XXX\XXX.pyz", line 34, in XXX
File "C:\Program Files (x86)\PyInstaller-2.1\PyInstaller\loader\pyi_importers.py", line 270, in load_module
File "C:\XXX\XXX\out00-PYZ.pyz\wmi", line 157, in <module>
File "C:\XXX\XXX\out00-PYZ.pyz\win32com.client", line 72, in GetObject
File "C:\XXX\XXX\out00-PYZ.pyz\win32com.client", line 87, in Moniker
wmi.py line 157 has a global call to GetObject:
obj = GetObject ("winmgmts:")
win32com\client__init.py__ contains GetObject(), which ends up calling Moniker():
def GetObject(Pathname = None, Class = None, clsctx = None):
"""
Mimic VB's GetObject() function.
ob = GetObject(Class = "ProgID") or GetObject(Class = clsid) will
connect to an already running instance of the COM object.
ob = GetObject(r"c:\blah\blah\foo.xls") (aka the COM moniker syntax)
will return a ready to use Python wrapping of the required COM object.
Note: You must specifiy one or the other of these arguments. I know
this isn't pretty, but it is what VB does. Blech. If you don't
I'll throw ValueError at you. :)
This will most likely throw pythoncom.com_error if anything fails.
"""
if clsctx is None:
clsctx = pythoncom.CLSCTX_ALL
if (Pathname is None and Class is None) or \
(Pathname is not None and Class is not None):
raise ValueError("You must specify a value for Pathname or Class, but not both.")
if Class is not None:
return GetActiveObject(Class, clsctx)
else:
return Moniker(Pathname, clsctx)
The first line in Moniker(), i.e. MkParseDisplayName() is where the exception is encountered:
def Moniker(Pathname, clsctx = pythoncom.CLSCTX_ALL):
"""
Python friendly version of GetObject's moniker functionality.
"""
moniker, i, bindCtx = pythoncom.MkParseDisplayName(Pathname)
dispatch = moniker.BindToObject(bindCtx, None, pythoncom.IID_IDispatch)
return __WrapDispatch(dispatch, Pathname, clsctx=clsctx)
Note: I tried using
pythoncom.CoInitialize()
which apparently solves this import problem within a thread, but that didn't work...

I also face the same issue and I figure out this issue finally,
import pythoncom and CoInitialize pythoncom.CoInitialize (). They import wmi
import pythoncom
pythoncom.CoInitialize ()
import wmi

I tried solving this countless ways. In the end, I threw in the towel and had to just find a different means of achieving the same goals I had with wmi.
Apparently that invalid syntax error is thrown when trying to create an object with an invalid "moniker name", which can simply mean the service, application, etc. doesn't exist on the system. Under this circumstance "winmgmts" just can't be found at all it seems! And yes, I tried numerous variations on that moniker with additional specs, and I tried running the service under a different user account, etc.

Honestly I didn't dig in order to understand why this occurs.
Anyway, the below imports solved my problem - which was occurring only when ran from a Flask instance:
import os
import pythoncom
pythoncom.CoInitialize()
from win32com.client import GetObject
import wmi

The error "com_error: (-2147221020, 'Invalid syntax', None, None)" is exactly what popped up in my case so I came here after a long time of searching the web and voila:
Under this circumstance "winmgmts" just can't be found at all it
seems!
This was the correct hint for because i had just a typo , used "winmgmt:" without trailing 's'. So invalid sythax refers to the first methods parameter, not the python code itself. o_0 Unfortunately I can't find any reference which objects we can get with win32com.client.GetObject()... So if anybody has a hint to which params are "allowed" / should work, please port it here. :-)
kind regards
ChrisPHL

ID3-mp3 editing in python - up-to-date package?

Edit: Trying to get these libraries to work in python 3.3 was clearly the wrong approach, and my problem now is entirely different so I'll just re-ask it in a new question.
I want to be able to edit ID3 tags of mp3 files with python commands, for example something like setAlbumName("folderPath\song.mp3", "albumname"). So far I've tried Mutagen, PyID3, pytagger, eyeD3, and they all seem to be outdated because the installation fails due to syntax errors. I tried to fix it in eyeD3, but I hit a dead end: http://i41.tinypic.com/o6zklv.png (second screenshot from after I had fixed all the prints and "except Error, e" and so on).
I tried the same with Mutagen, but I ran into a wall there as well when replacing "raise KeyError, key" with "raise KeyError as key" didn't work.
I didn't even know what to make of this one (pytagger): http://i41.tinypic.com/29fz7mh.png
It seems to suggest that there's something wrong with my python installation? Not getting into that.
So, would anyone like to point me to an ID3 package that works, or have a go at fixing an outdated one?
(Also, I tried both "python setup.py install" and "setup.py install" and it seemed to make no difference. I'm on windows 8.)
Edit: From the screenshot below, plus the source code (mutagen with python 2.7.5)
from mutagen.mp3 import MP3
p = "E:\\Musik\\Aeon\\2005 Bleeding the False\\01 Cenobites - Copy.mp3"
audio = MP3(p)
audio["title"] = "An example"
audio.pprint()
audio.save()
_
Traceback (most recent call last):
File "id3tag.py", line 5, in <module>
audio.pprint()
File "C:\Python27\lib\site-packages\mutagen\__init__.py", line 138, in pprint
try: tags = self.tags.pprint()
File "C:\Python27\lib\site-packages\mutagen\id3.py", line 190, in pprint
frames = list(map(Frame.pprint, self.values()))
TypeError: unbound method pprint() must be called with Frame instance as first a
rgument (got str instance instead)
_
from mutagen.mp3 import MP3
p = "E:\\Musik\\Aeon\\2005 Bleeding the False\\01 Cenobites - Copy.mp3"
audio = MP3(p)
audio["title"] = "An example"
audio.save()
_
Traceback (most recent call last):
File "id3tag.py", line 7, in <module>
audio.save()
File "C:\Python27\lib\site-packages\mutagen\__init__.py", line 132, in save
return self.tags.save(filename, **kwargs)
File "C:\Python27\lib\site-packages\mutagen\id3.py", line 370, in save
framedata = [self.__save_frame(frame) for (key, frame) in frames]
File "C:\Python27\lib\site-packages\mutagen\id3.py", line 461, in __save_frame
framedata = frame._writeData()
AttributeError: 'str' object has no attribute '_writeData'

mutagen works great for me with Python 2.7.
examples:
https://code.google.com/p/mutagen/wiki/Tutorial
from mutagen.mp3 import MP3
audio = MP3("example.mp3")
audio["title"] = "An example"
audio.pprint()
audio.save()
p.s. please post code samples so people can help.. not links to screenshots.
p.p.s. it looks like you are trying to install Python2 libs into Python3.

Mutagen also has an EasyID3 tool, which handles simple tasks like changing the file's title:
from mutagen.easyid3 import EasyID3
f = EasyID3("file.mp3")
f["title"] = u"Some title"
f.save()
Works like a charm. But it has very restricted functionality.
See more examples at http://code.google.com/p/mutagen/wiki/Tutorial

errors with gae-sessions and nose

I'm running into a few problems with adding gae-sessions to a relatively mature GAE app. I followed the readme carefully and also looked at the demo.
First, just adding the gaesesions directory to my app causes the following error when running tests with nose and nose-gae:
Exception ImportError: 'No module named threading' in <bound method local.__del__ of <_threading_local.local object at 0x103e10628>> ignored
All the tests run fine so not a big problem but suggests that something isn't right.
Next, if I add the following two lines of code:
from gaesessions import get_current_session
session = get_current_session()
And run my tests, then I get the following error:
Traceback (most recent call last):
File "/Users/.../unit_tests.py", line 1421, in testParseFBRequest
data = tasks.parse_fb_request(sr)
File "/Users/.../tasks.py", line 220, in parse_fb_request
session = get_current_session()
File "/Users/.../gaesessions/__init__.py", line 36, in get_current_session
return _tls.current_session
File "/Library/.../python2.7/_threading_local.py", line 193, in __getattribute__
return object.__getattribute__(self, name)
AttributeError: 'local' object has no attribute 'current_session'
This error does not happen on the dev server.
Any suggestions on fixing the above would be greatly appreciated.

I ran into the same problem. The problem seems to be that the gae testbed behaves differently than the development server. I don't know the specifics but ended up solving it by adding
def setUp(self):
testbed.Testbed().activate()
# after activating the testbed:
from gaesessions import Session, set_current_session
set_current_session(Session())