OpenGL and OpenCV with python 2.7 - part 004.

Today I will continue the series of graphics processing in OpenGL and OpenCV.
The goal of this tutorial is the download and load into the python script of a youtube video.
To do that we need another two modules python.
First, I download and install the python 2.7.12 32 bit version from the internet.
C:\Python27>python.exe
Python 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:19:22) [MSC v.1500 32 bit (
Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
First update the pip tool and install numpy python module:
C:\Python27\Scripts>python -m pip install --upgrade pip
Collecting pip
Downloading pip-9.0.1-py2.py3-none-any.whl (1.3MB)
100% |################################| 1.3MB 419kB/s
Installing collected packages: pip
Found existing installation: pip 8.1.1
Uninstalling pip-8.1.1:
Successfully uninstalled pip-8.1.1
Successfully installed pip-9.0.1
C:\Python27\Scripts>pip install numpy
Collecting numpy
Downloading numpy-1.11.2-cp27-none-win32.whl (6.5MB)
100% |################################| 6.5MB 79kB/s
Installing collected packages: numpy
Successfully installed numpy-1.11.2

The main reason to have the numpy python module: it is often used with OpenCV python module.
For OpenCV python module installation you need to see my tutorial.
After you install it, test the OpenCV python module:
C:\Python27>python.exe
Python 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:19:22) [MSC v.1500 32 bit (
Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import cv2
>>> print cv2.__version__
3.0.0
Install pafy python module.
This module help you to download video from youtube but you need also the youtube-dl python module.
So let's install the youtube-dl and pafy python modules.
C:\Python27>cd Scripts
C:\Python27\Scripts>pip install youtube-dl
Collecting youtube-dl
Downloading youtube_dl-2016.12.1-py2.py3-none-any.whl (1.5MB)
100% |################################| 1.5MB 377kB/s
Installing collected packages: youtube-dl
Successfully installed youtube-dl-2016.12.1
C:\Python27\Scripts>pip install pafy
Collecting pafy
Downloading pafy-0.5.2-py2.py3-none-any.whl
Installing collected packages: pafy
Successfully installed pafy-0.5.2

I make a simple python script named: get_yt.py.
The source code of this script is simple:
import os
import pafy
# Download the video
video = pafy.new('https://www.youtube.com/watch?v=O5VCjktWVD4')
print "video.title"
print video.title
print "video.rating"
print video.rating
print "video.viewcount, video.author, video.length"
print video.viewcount, video.author, video.length
print "video.duration, video.likes, video.dislikes"
print video.duration, video.likes, video.dislikes
print "video.description"
print video.description
resolution = video.getbestvideo(preftype="mp4")
print "resolution"
print resolution
input_movie = resolution.download(quiet=False)
print "input_movie"
print input_movie
print "delete movie"
os.remove(input_movie)

I used the URL of a video clip from youtube channel of Arden Cho to tested.
If you want to keep the video into your folder just remove the last line from the python script.
The result is this output:
C:\Python27>python.exe get_yt.py
video.title
Can't Help Falling in Love With You - Arden Cho
video.rating
4.99041318893
video.viewcount, video.author, video.length
10980 ardenBcho 168
video.duration, video.likes, video.dislikes
00:02:48 1665 4
video.description
Recorded this song a couple months ago when I was in Boston, this song always reminds
me of holidays and love so sharing that with you!

Guitar by Koo Chung https://youtube.com/koochung
Violin and Video editing/production by Daniel Jang https://www.youtube.com/metal
sides
Production + Keys by Tim Bongiovanni https://www.northgateproductions.net
Filmed by Rob Mark https://www.instagram.com/rmarq_

If you like my music comment and SHARE! You can also support me by buying & rati
ng my album on iTunes!! https://itunes.apple.com/us/album/my-true-happy/id592588
859

You can follow me at: SnapChat: ardencho
http://www.instagram.com/arden_cho
http://www.facebook.com/hiardencho
http://www.twitter.com/arden_cho
http://www.imdb.me/ardencho
resolution
video:mp4@1920x1080
input_movie5 Bytes [100.00%] received. Rate: [5371 KB/s]. ETA: [0 secs]
Can't Help Falling in Love With You - Arden Cho.mp4
delete movie

Python and OAuth2 with Google API.

If you want to do this then is simple to do. The most complex part comes from google settings.
But that can be easy if you make it from a few times.
I used OAuth2 with JSON file to make authentification.
You can see my full tutorial here.

Using text file with python 2.7 .

This simple tutorial is about text file. The text file come with txt extension.
It is a file containing text that can be used and further processing by functions and modules python.
I used Tkinter python module. The reason I chose this python mpodule is:

• old python module;
• rapidly developing graphical interfaces.

First step is to import the python module and then to put all of dir command into one text file.
The name of this file is: Tkinter_funct.txt
Open your python and try this source code:
C:\Python27>python.exe
Python 2.7.8 (default, Jun 30 2014, 16:08:48) [MSC v.1500 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import Tkinter
>>> from Tkinter import *
>>> Tkinter_all=dir(Tkinter)
>>> Tkinter_file=open('Tkinter_funct.txt','w')
>>> Tkinter_file.write(str(Tkinter_all))
>>> print Tkinter_all
You will see the content of dir python module.
The text file is also have this text output.
To read the file is need to open the file with open function, to put position for read by using seek function and to read with read function.
This example will show you how is working:
>>> test=open('Tkinter_funct.txt','r+')
>>> test.seek(1)
>>> test.read()
Will open the file named Tkinter_funct.txt and r+ access to file.
The position it is set to 1.
The read function make all with full content output.
Now let's see the next steps, by change the read and seek values.

>>> test.read(1)
''
>>> test.read(2)
''
>>> test.read(10)
''
>>> test.seek(2)
>>> test.read(1)
'A'
>>> test.read(10)
"CTIVE', 'A"
>>> test.read(20)
"LL', 'ANCHOR', 'ARC'"
This outputs come with parts of all content and show you how it's working.

The python CacheControl module - part 002.

Today was a hard day and this is the reason I make this short tutorial.
Teory of HTTP:
HTTP specifies four response cache headers that you can set to enable caching:

• Cache-Control
• Expires
• ETag
• Last-Modified

These four headers are used to help cache your responses into two different models:

• Expiration Caching - used to cache your entire response for a specific amount of time (e.g. 24 hours), simple, but cache invalidation is more difficult;
• Validation Caching - this is more complex and used to cache your response, but allows you to dynamically invalidate it as soon as your content changes.

First you need to know about this code is a raw example about how we can access cache of the page.
Come with a simple class named DictCache. You can named with any name and is a BaseCache class.
The next step I make is to show you how can access it.
One simpe way is to see the page - first session.
The complex come when you need to access for example data and info like:
 'adapters', 'auth', 'cert', 'close', 'cookies', 'delete', 'get', 'get_adapter', 'head', 'headers', 'hooks', 'max_redirects', 'merge_environment_settings', 'mount', 'options', 'params', 'patch', 'post', 'prepare_request', 'proxies', 'put', 'rebuild_auth', 'rebuild_method', 'rebuild_proxies', 'redirect_cache', 'request', 'resolve_redirects', 'send', 'stream', 'trust_env', 'verify'
And this is come with teh second session from this source code:

import requests
from cachecontrol import CacheControl
from cachecontrol.cache import BaseCache

class DictCache(BaseCache):

    def __init__(self, init_dict=None):
        self.data = init_dict or {}

    def get(self, key):
        return self.data.get(key, None)

    def set(self, key, value):
        self.data.update({key: value})

    def delete(self, key):
        self.data.pop(key)

print "first session requests"
sess = requests.session()
cached_sess = CacheControl(sess)
response = cached_sess.get('http://google.com')
print '=================='
print 'see page by add this: print response.text'
print '=================='
print "second session BaseCache"
sess2 = requests.session()
base=DictCache(sess2)
print '=================='
print "dir(base)"
print dir(base)
print '=================='
print"dir(base.data)"
print dir(base.data)
print '=================='
print"base.data.max_redirects"
print base.data.max_redirects
print '=================='