Python 3.7.11 : My colab tutorials - part 018.

In this colab tutorial, you can see how to use the webcam with python and javascript.

This colab notebook can be found on my colab project on the GitHub webpage.

• catafest_001.ipynb - first step, import TensorFlow;
• catafest_002.ipynb - testing the GPU , Linux commands and python modules torch and fastai;
• catafest_003.ipynb - testing the Altair;
• catafest_004.ipynb - testing the cirq python package for quantum computing;
• catafest_005.ipynb - using the estimator on tensoflow 2.0;
• python_imdb_001.ipynb - using the colab with python module imdbpy;
• catafest_006.ipynb - google authentification and google.colab drive and files
• catafest_007.ipynb - test with https://github.com/harrism/numba_examples/blob/master/mandelbrot_numba.ipynb
• catafest_008.ipynb - few simple examples with selenium and chromium-chromedriver;
• catafest_009.ipynb - show you how to use %% colab features;
• catafest_010.ipynb - example with Detectron2 is Facebook AI Research's with state-of-the-art object detection algorithms;
• catafest_011.ipynb - test a sound classification with YAMNet from a web example - not very happy with the result;
• catafest_012.ipynb - a simple tutorial about Colab tool and HTML and JavaScript with examples;
• catafest_013.ipynb - a simple tutorial with settings for TPU and IMDB dataset;
• catafest_014.ipynb - get IMDB review dataset and show it;
• catafest_015.ipynb - how to get, show and use it data and create a new train data set from IMDB dataset;
• catafest_016.ipynb - show the shape of the Fashion-MNIST dataset;
• catafest_017.ipynb - this example show you how to write another python script in colab and run it;
• catafest_018.ipynb - PIFuHD demo;
• catafest_019.ipynb - get title from tiles.virtualearth.net;
• catafest_020.ipynb - get video from youtube with pytube, converting to audio, show signal wave, energy and frequency;
• catafest_021.ipynb - BERT is a transformers model with example and sentiment-analysis;
• catafest_022.ipynb - webcam on colab with python and javascript;

Python 3.7.11 : My colab tutorials - part 017.

BERT: Pre-training of Deep Bidirectional Transformers for Language Understanding, see this https://arxiv.org/abs/1810.04805.

I used transformers, see this video: https://www.youtube.com/watch?v=SZorAJ4I-sA and this: https://arxiv.org/pdf/2003.08271.pdf.

See this colab notebook with examples at my GitHub account.

Python 3.7.11 : My colab tutorials - part 016.

This new colab notebook comes with: get youtube videos with pytube, converting to audio, show signals, energy and frequency.

You can see this work on the GitHub account.

Python 3.7.11 : My colab tutorials - part 015.

Google Maps explicitly forbid using map tiles offline or caching them, but I think Microsoft Bing Maps don't say anything explicitly against it, and I guess you are not planning to use your program commercially (?)

This colab notebook show you how to get a title from tiles.virtualearth.net.

The source code is simple:

class TileServer(object):
    def __init__(self):
        self.imagedict = {}
        self.mydict = {}
        self.layers = 'ROADMAP'
        self.path = './'
        self.urlTemplate = 'http://ecn.t{4}.tiles.virtualearth.net/tiles/{3}{5}?g=0'
        self.layerdict = {'SATELLITE': 'a', 'HYBRID': 'h', 'ROADMAP': 'r'}

    def tiletoquadkey(self, xi, yi, z, layers):
        quadKey = ''
        for i in range(z, 0, -1):
            digit = 0
            mask = 1 << (i - 1)
            if(xi & mask) != 0:
                digit += 1
            if(yi & mask) != 0:
                digit += 2
            quadKey += str(digit)
        return quadKey

    def loadimage(self, fullname, tilekey):
        im = Image.open(fullname)
        self.imagedict[tilekey] = im
        return self.imagedict[tilekey]

    def tile_as_image(self, xi, yi, zoom):
        tilekey = (xi, yi, zoom)
        result = None
        try:
            result = self.imagedict[tilekey]
            print(result)
        except:
            print(self.layers)
            filename = '{}_{}_{}_{}.jpg'.format(zoom, xi, yi, self.layerdict[self.layers])
            print("filename is " + filename)
            fullname = self.path + filename
            try:
                result = self.loadimage(fullname, tilekey)
            except:
                server = random.choice(range(1,4))
                quadkey = self.tiletoquadkey(*tilekey)
                print (quadkey)
                url = self.urlTemplate.format(xi, yi, zoom, self.layerdict[self.layers], server, quadkey)
                print ("Downloading tile %s to local cache." % filename)
                urllib.request.urlretrieve(url, fullname)
                #urllib.urlretrieve(url, fullname)
                result = self.loadimage(fullname, tilekey)
        return result

Simple install of python in Windows O.S.

Today I create this simple video tutorial for new python users.

In this video tutorial I show you how easy is to install the python programming language in Windows O.S.

After install you can use the command python and you can use the python shell to test this programming language.

Also, you can create a script file with any name.

for example name the file: test.py and run in the windows shell with: python test.py.

You can see this video tutorial on my youtube account.

Python Qt6 : Install and use python with Visual Studio.

Visual Studio is a very good tool for python programming language development.

Today I will show you how to use it with Visual Studio on a Windows operating system.

If you don't have Python install then start the Visual Studio installer and from all presents select the Python development workload.

Start Visual Studio and open a folder or open an empty file and save with the python language-specific extension: py.

Select the Python environment and add the new package with pip tool.

This is the python script I used to test:

import sys
from PyQt6.QtWidgets import QApplication, QWidget

def main():

    app = QApplication(sys.argv)

    w = QWidget()
    w.resize(250, 200)
    w.move(300, 300)

    w.setWindowTitle('Simple')
    w.show()

    sys.exit(app.exec())

if __name__ == '__main__':
    main()

You can see the video tutorial about how you can use it:

Python Qt6 : First example on Fedora 34 Linux distro.

Qt for Python is the project that provides the official set of Python bindings (PySide6) that will supercharge your Python applications. While the Qt APIs are world renowned, there are more reasons why you should consider Qt for Python.

I tested with Fedora 34 Linux distro:

[root@desk mythcat]# dnf search PyQt6
Last metadata expiration check: 2:03:10 ago on Tue 06 Jul 2021 08:52:41 PM EEST.
No matches found. 

First stable release for PyQt6 was on Jan 2021 by Riverbank Computing Ltd. under GPL or commercial and can be used with Python 3.

Let's install with pip tool:

[mythcat@desk ~]$ /usr/bin/python3 -m pip install --upgrade pip
...
  WARNING: The scripts pip, pip3 and pip3.9 are installed in '/home/mythcat/.local/bin' which is not on PATH.
  Consider adding this directory to PATH or, if you prefer to suppress this warning, 
  use --no-warn-script-location.
Successfully installed pip-21.1.3
[mythcat@desk ~]$ pip install PyQt6 --user
...

Let's see a simple example with this python package:

import sys
from PyQt6.QtCore import Qt
from PyQt6.QtWidgets import QApplication, QLabel

def main():
    app = QApplication(sys.argv)
    win = QLabel()
    win.resize(640, 498)
    win.setText("Qt is awesome!!!")
    win.show()
    app.exec()

if __name__ == "__main__":
    main()

I tested and run well.

Python Qt5 : Parse files and show image with QPixmap .

This tutorial is about how to create a simple script in python with a few features:

You can see I used these python packages: argparse, PIL, glob, io, PyQt5 to fulfill the issue.

The PIL python package is used to use PNG images.

The argparse python package is used to get inputs from arguments.

The glob python package is used to parse folders and files.

The io python package is used to open images:

The PyQt5 python package is used to show images on canvas:

This is the source code in python I used to parse a folder with images and show one image:

import os
import io
import sys
import glob

from PIL import Image
from PIL import UnidentifiedImageError

from PyQt5.QtGui import QPixmap
from PyQt5.QtWidgets import QMainWindow, QApplication, QLabel

import argparse
from pathlib import Path

parser = argparse.ArgumentParser()

parser.add_argument("files_path", type=Path, help='PATH of folder with files ')
parser.add_argument('-p','--print_files', action='store_true', 
    help='Print files from folder ')
parser.add_argument('-s','--show', action='store_true', 
    help='Show image in PyQt5 canvas!')
args = vars(parser.parse_args())

p = parser.parse_args()
print(p.files_path, type(p.files_path), p.files_path.exists())
print(p.show)
files = os.listdir(p.files_path)
file_list = []
image_list = []
bad_files_list =[]

if args['print_files']: 
    print("These are files from folder "+str(p.files_path))
    for f in file_list:
	    print(f)

images_ext = str(Path(p.files_path))+'/*.png'
print("images_ext: "+images_ext)
for filename in glob.glob(images_ext): #assuming png
    try:
        f = open(filename, 'rb')
        file = io.BytesIO(f.read())
        im = Image.open(file)
        image_list.append(filename)
        print(str(len(image_list))+" good file is"+filename)
    except Image.UnidentifiedImageError:
        bad_files_list.append(str(p.files_path)+"/"+str(filename))

for f in bad_files_list:
	print("bad file is : " + f)


if args['show']:
    value = input("Please enter the index of PNG image :\n")
    try:
        int(value)
        print("Image number select default : " + value)      
        value = int(value)
        if value &lt= len(image_list):
            value = int(value)
        else:
            print("The number image selected is greater then len of list images!")
            value = len(image_list)
    except:
        print("This is not a number, I set first image number.")
        value = 1

    class MainWindow(QMainWindow):

        def __init__(self):
            super(MainWindow, self).__init__()
            self.title = "Image Viewer"
            self.setWindowTitle(self.title)

            label = QLabel(self)
            pixmap = QPixmap(image_list[int(value)])
            label.setPixmap(pixmap)
            self.setCentralWidget(label)
            self.resize(pixmap.width(), pixmap.height())

    app = QApplication(sys.argv)
    w = MainWindow()
    w.show()
    sys.exit(app.exec_())

These are the output of the script:

[mythcat@desk PIL001]$ python  tool001.py 
usage: tool001.py [-h] [-p] [-s] files_path
tool001.py: error: the following arguments are required: files_path
[mythcat@desk PIL001]$ python  tool001.py ~/Pictures/
/home/mythcat/Pictures  True
False
images_ext: /home/mythcat/Pictures/*.png
1 good file is/home/mythcat/Pictures/keyboard.png
2 good file is/home/mythcat/Pictures/Fedora_The_Pirate_CaribbeanHunt.png
3 good file is/home/mythcat/Pictures/website.png
4 good file is/home/mythcat/Pictures/Screenshot from 2021-02-19 19-24-32.png
...
97 good file is/home/mythcat/Pictures/Screenshot from 2021-07-03 17-31-23.png
98 good file is/home/mythcat/Pictures/Screenshot from 2021-07-03 17-46-05.png
bad file is : /home/mythcat/Pictures//home/mythcat/Pictures/Screenshot from 2021-02-07 14-58-56.png
bad file is : /home/mythcat/Pictures//home/mythcat/Pictures/evolution_logo.png
[mythcat@desk PIL001]$ python  tool001.py ~/Pictures/ -p
/home/mythcat/Pictures  True
False
These are files from folder /home/mythcat/Pictures
images_ext: /home/mythcat/Pictures/*.png
1 good file is/home/mythcat/Pictures/keyboard.png
2 good file is/home/mythcat/Pictures/Fedora_The_Pirate_CaribbeanHunt.png
3 good file is/home/mythcat/Pictures/website.png
...
97 good file is/home/mythcat/Pictures/Screenshot from 2021-07-03 17-31-23.png
98 good file is/home/mythcat/Pictures/Screenshot from 2021-07-03 17-46-05.png
bad file is : /home/mythcat/Pictures//home/mythcat/Pictures/Screenshot from 2021-02-07 14-58-56.png
bad file is : /home/mythcat/Pictures//home/mythcat/Pictures/evolution_logo.png
[mythcat@desk PIL001]$ python  tool001.py ~/Pictures/ -s
/home/mythcat/Pictures  True
True
images_ext: /home/mythcat/Pictures/*.png
...
97 good file is/home/mythcat/Pictures/Screenshot from 2021-07-03 17-31-23.png
98 good file is/home/mythcat/Pictures/Screenshot from 2021-07-03 17-46-05.png
bad file is : /home/mythcat/Pictures//home/mythcat/Pictures/Screenshot from 2021-02-07 14-58-56.png
bad file is : /home/mythcat/Pictures//home/mythcat/Pictures/evolution_logo.png
Please enter the index of PNG image :
6
Image number select default : 6

Python 3.6.9 : My colab tutorials - part 014.

Here we come to the 16th notebook created with the colab utility from Google.

In this notebook, I will show you how you can view a dataset of images.

See the next image with a few of the shapes of the dataset:

You can find the full source code on my GitHub account.

Python 3.6.9 : My colab tutorials - part 013.

In this tutorial created with the online tool google colab, we exemplified again how to access the IMDB dataset, which contains from the index point of view and what is the correspondence with the IMDB reviews, as well as how to work and create several sets of data for trains and what is the difference between them.

You can see the source code in python on this notebook.

Python 3.6.9 : My colab tutorials - part 012.

The purpose of this tutorial is to show the IMDB review dataset.

You can find the source code on my GitHub account here.

Python 3.6.9 : My colab tutorials - part 011.

The purpose of this tutorial is to use the google TPU device together with Keras.

You need to set from the Edit menu and set for the notebook the device called TPU.

You can find the source code on my GitHub account here.

Python 3.9.1 : ABC - Abstract Base Classes - part 001.

Abstract classes are classes that contain one or more abstract methods.

By default, Python does not provide abstract classes.

Python comes with a module that provides the base for defining Abstract Base Classes (named ABC).

An abstract class can be considered as a blueprint for other classes.

By defining an abstract base class, you can define a common API for a set of subclasses.

A class that is derived from an abstract class cannot be instantiated unless all of its abstract methods are overridden.

[mythcat@desk ~]$ python3.9
Python 3.9.5 (default, May  4 2021, 00:00:00) 
[GCC 10.3.1 20210422 (Red Hat 10.3.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from abc import ABC
>>> class Test_ABC(ABC):
...     pass
... 
>>> Test_ABC.register(tuple)

>>> assert issubclass(tuple,Test_ABC)
>>> assert isinstance((), Test_ABC)
>>> class Foo:
...     def __getitem__(self, index):
...         ...
...     def __len__(self):
...         ...
...     def get_iterator(self):
...         return iter(self)
... 
>>> Test_ABC.register(Foo)
...

Let's see an example:

from abc import ABC, abstractmethod
 
class Vehicle(ABC):
    @abstractmethod
    def action(self):
        pass

class Air(Vehicle):
    # overriding abstract method
    def action(self):
        print("this flies in the air")
 
class Ground(Vehicle):
    # overriding abstract method
    def action(self):
        print("this running on the field")

class Civil(Ground):
    def action(self):
        print("Civil class - running on the field")

# Can't instantiate abstract class with abstract method action, don't use it
# abc = Vehicle()

abc = Air()
abc.action()

abc = Ground()
abc.action()

abc = Civil()
abc.action()

print( issubclass(Civil, Vehicle))
print( isinstance(Civil(), Vehicle))

This is the result:

[mythcat@desk PythonProjects]$ python3.9 ABC_001.py 
this flies in the air
this running on the field
Civil class - running on the field
True
True