Python Tutorial

Introduction Python Features Python Applications Python System requirements Python Installation Python Examples Python Basics Python Indentation Python Variables Python Data Types Python IDE Python Keywords Python Operators Python Comments Python Pass Statement

Python Conditional Statements

Python if Statement Python elif Statement Python If-else statement Python Switch Case

Python Loops

Python for loop Python while loop Python Break Statement Python Continue Statement Python Goto Statement

Python Arrays

Python Array Python Matrix

Python Strings

Python Strings Python Regex

Python Built-in Data Structure

Python Lists Python Tuples Python Lists vs Tuples Python Dictionary Python Sets

Python Functions

Python Function Python min() function Python max() function Python User-define Functions Python Built-in Functions Python Recursion Anonymous/Lambda Function in Python apply() function in python Python lambda() Function

Python File Handling

Python File Handling Python Read CSV Python Write CSV Python Read Excel Python Write Excel Python Read Text File Python Write Text File Read JSON File in Python

Python Exception Handling

Python Exception Handling Python Errors and exceptions Python Assert

Python OOPs Concept

OOPs Concepts in Python Classes & Objects in Python Inheritance in Python Polymorphism in Python Python Encapsulation Python Constructor Python Super function Python Static Method Static Variables in Python Abstraction in Python

Python Iterators

Iterators in Python Yield Statement In Python Python Yield vs Return

Python Generators

Python Generator

Python Decorators

Python Decorator

Python Functions and Methods

Python Built-in Functions Python String Methods Python List Methods Python Dictionary Methods Python Tuple Methods Python Set Methods

Python Modules

Python Modules Python Datetime Module Python Math Module Python Import Module Python Time ModulePython Random Module Python Calendar Module CSV Module in Python Python Subprocess Module

Python MySQL

Python MySQL Python MySQL Client Update Operation Delete Operation Database Connection Creating new Database using Python MySQL Creating Tables Performing Transactions

Python MongoDB

Python MongoDB

Python SQLite

Python SQLite

Python Data Structure Implementation

Python Stack Python Queue Python Linked List Python Hash Table Python Graph

Python Advance Topics

Speech Recognition in Python Face Recognition in Python Python Linear regression Python Rest API Python Command Line Arguments Python JSON Python Subprocess Python Virtual Environment Type Casting in Python Python Collections Python Attributes Python Commands Python Data Visualization Python Debugger Python DefaultDict Python Enumerate

Python 2

What is Python 2

Python 3

Anaconda in Python 3 Anaconda python 3 installation for windows 10 List Comprehension in Python3

How to

How to Parse JSON in Python How to Pass a list as an Argument in Python How to Install Numpy in PyCharm How to set up a proxy using selenium in python How to create a login page in python How to make API calls in Python How to run Python code from the command prompt How to read data from com port in python How to Read html page in python How to Substring a String in Python How to Iterate through a Dictionary in Python How to convert integer to float in Python How to reverse a string in Python How to take input in Python How to install Python in Windows How to install Python in Ubuntu How to install PIP in Python How to call a function in Python How to download Python How to comment multiple lines in Python How to create a file in Python How to create a list in Python How to declare array in Python How to clear screen in Python How to convert string to list in Python How to take multiple inputs in Python How to write a program in Python How to compare two strings in Python How to create a dictionary in Python How to create an array in Python How to update Python How to compare two lists in Python How to concatenate two strings in Python How to print pattern in Python How to check data type in python How to slice a list in python How to implement classifiers in Python How To Print Colored Text in Python How to open a file in python How to Open a file in python with Path How to run a Python file in CMD How to change the names of Columns in Python How to Concat two Dataframes in Python How to Iterate a List in Python How to learn python Online How to Make an App with Python How to develop a game in python How to print in same line in python How to create a class in python How to find square root in python How to import numy in python How to import pandas in python How to uninstall python How to upgrade PIP in python How to append a string in python How to comment out a block of code in Python How to change a value of a tuple in Python How to append an Array in Python How to Configure Python Interpreter in Eclipse Parameter Passing in Python How to plot a Histogram in Python How to Import Files in Python How to Download all Modules in Python How to get Time in seconds in Python How to Practice Python Programming How to plot multiple linear regression in Python How to set font for Text in Python

Sorting

Python Sort List Sort Dictionary in Python Python sort() function Python Bubble Sort

Programs

Factorial Program in Python Prime Number Program in Python Fibonacci Series Program in Python Leap Year Program in Python Palindrome Program in Python Check Palindrome In Python Calculator Program in Python Armstrong Number Program in Python Python Program to add two numbers Anagram Program in Python Number Pattern Programs in Python Even Odd Program in Python GCD Program in Python Python Exit Program Python Program to check Leap Year Operator Overloading in Python Pointers in Python Python Not Equal Operator Raise Exception in Python Salary of Python Developers in India What is a Script in Python

Misc

Introduction to Scratch programming SKLearn Clustering SKLearn Linear Module Standard Scaler in SKLearn Python Time Library SKLearn Model Selection Standard Scaler in SKLearn Accuracy_score Function in Sklearn Append key Value to Dictionary in Python Cross Entropy in Python Cursor in Python Data Class in Python How to Install Tweepy in Python Imread Python Program of Cumulative Sum in Python Python Program for Linear Search Python Program to Generate a Random String Read numpy array in Python Scrimba python Sklearn linear Model in Python Scraping data in python Accessing Key-value in Dictionary in Python Find Median of List in Python Linear Regression using Sklearn with Example Problem-solving with algorithm and data structures using Python Python 2.7 data structures Python Variable Scope with Local & Non-local Examples Arguments and parameters in Python Assertion error in python Programs for Printing Pyramid Patterns in Python _name_ in Python Amazon rekognition using python Anaconda python 3.7 download for windows 10 64-bit Android apps for coding in python Augmented reality in python Best app for python Difference between Perl and Python Not supported between instances of str and int in python Python comment symbol Python Complex Class Python IDE names Selection Sort Using Python Hypothesis Testing in Python Idle python download for Windows Insertion Sort using Python Merge Sort using Python Python - Binomial Distribution Python Logistic Regression with Sklearn & Scikit Python Random shuffle() method Python variance() function Python vs HTML Removing the First Character from the String in Python Adding item to a python dictionary Best books for NLP with Python Best Database for Python Count Number of Keys in Dictionary Python Cross Validation in Sklearn Drop() Function in Python EDA in Python Excel Automation with Python Python Program to Find the gcd of Two Numbers Python Web Development projects Adding a key-value pair to dictionary in Python Python Euclidean Distance Python Filter List Python Fit Transform Python e-book free download Python email utils Python range() Function Python random.seed() function What is the re.sub() function in Python Python PPTX Python Pickle Python Seaborn Python Coroutine Python EOL Python Infinity Python math.cos and math.acos function Python Project Ideas Based On Django Reverse a String in Python Reverse a Number in Python Python Word Tokenizer Python Trigonometric Functions Python try catch exception GUI Calculator in Python Implementing geometric shapes into the game in python Installing Packages in Python Python Try Except Python Sending Email Socket Programming in Python Python CGI Programming Python Data Structures Python abstract class Python Compiler Python K-Means Clustering NSE Tools In Python Operator Module In Python Palindrome In Python Permutations in Python Pillow Python introduction and setup Python Functionalities of Pillow Module Python Argmin Python whois Python JSON Schema Python lock Return Statement In Python Reverse a sentence In Python tell() function in Python Why learn Python? Write Dictionary to CSV in Python Write a String in Python Binary Search Visualization using Pygame in Python Latest Project Ideas using Python 2022 Closest Pair of Points in Python ComboBox in Python Python vs R Best resources to learn Numpy and Pandas in python Check Letter in a String Python Python Console Python Control Statements Convert Float to Int in Python using Pandas Difference between python list and tuple Importing Numpy in Pycharm Python Key Error Python NewLine Python tokens and character set Python Strong Number any() Keyword in python Best Database in Python Check whether dir is empty or not in python Comments in the Python Programming Language Convert int to Float in Python using Pandas Decision Tree Classification in Python End Parameter in python __GETITEM__ and __SETITEM__ in Python Python Namespace Python GUI Programming List Assignment Index out of Range in Python List Iteration in Python List Index out of Range Python for Loop List Subtract in Python Python Empty Tuple Python Escape Characters Sentence to python vector Slicing of a String in Python Executing Shell Commands in Python Genetic Algorithm in python Get index of element in array in python Looping through Data Frame in Python Syntax of Map function in Python After Python What Should I Learn Python AIOHTTP Alexa Python Artificial intelligence mini projects ideas in python Artificial intelligence mini projects with source code in Python Find whether the given stringnumber is palindrome or not First Unique Character in a String Python Python Network Programming Python Interface Python Multithreading Python Interpreter Data Distribution in python Flutter with tensor flow in python Front end in python Iterate a Dictionary in Python Iterate a Dictionary in Python – Part 2 Allocate a minimum number of pages in python Assertion Errors and Attribute Errors in Python Checking whether a String Contains a Set of Characters in python Python Control Flow Statements *Args and **Kwargs in Python Bar Plot in Python Conditional Expressions in Python Function annotations() in Python How to Write a Configuration file in Python Image to Text in python import() Function in Python Import py file in Python Multiple Linear Regression using Python Nested Tuple in Python Python String Negative Indexing Reading a File Line by Line in Python Python Comment Block Base Case in Recursive function python ER diagram of the Bank Management System in python Image to NumPy Arrays in Python NOT IN operator in Python One Liner If-Else Statements in Python Sklearn in Python Cube Root in Python Python Variables, Constants and Literals What Does the Percent Sign (%) Mean in Python Creating Web Application in python Notepad++ For Python PyPi TensorFlow Python | Read csv using pandas.read_csv() What is online python free IDE What is Python online compiler Run exec python from PHP What are the Purposes of Python What is Python compiler GDB Python coding platform Python Classification Python | a += b is not always a = a + b PyDev with Python IDE Character Set in Python Best Python AI Projects _dict_ in Python Python Ternary Operators Self in Python Python vs Java Python Modulo Python Packages Python Syntax Python Uses Python Bitwise Operators Python Identifiers Python Matrix Multiplication Python AND Operator Python Logical Operators Python Multiprocessing Python Unit Testing __init__ in Python Advantages of Python Is Python Case-sensitive when Dealing with Identifiers Python Boolean Python Call Function Python History Python Image Processing Python main() function Python Permutations and Combinations Difference between Input() and raw_input() functions in Python Conditional Statements in python Confusion Matrix Visualization Python Nested List in Python Python Algorithms Python Modules List Difference between Python 2 and Python 3 Is Python Case Sensitive Method Overloading in Python Python Arithmetic Operators Assignment Operators in Python Is Python Object Oriented Programming language Python Division Python exit commands Continue And Pass Statements In Python Colors In Python Convert String Into Int In Python Convert String To Binary In Python Convert Uppercase To Lowercase In Python Convert XML To JSON In Python Converting Set To List In Python Covariance In Python CSV Module In Python Decision Tree In Python Difference Between Yield And Return In Python Dynamic Typing In Python BOTTLE Python Web Framework How to Install Scikit-Learn Introducing modern python computing in simple packages Python vs PHP Reason for Python So Popular Returning Multiple Values in Python Spotify API in Python Spyder (32-bit) - Free download Time. Sleep() in Python Traverse Dictionary in Python What is Ipython shell YOLO Python Nested for Loop in Python Data Structures and Algorithms Using Python | Part 1 Data Structures and Algorithms using Python | Part 2 ModuleNotFoundError No module named 'mysql' in Python N2 in Python XGBoost for Regression in Python Explain sklearn clustering in Python Data Drop in Python Falcon Python Flutter Python Google Python Class Excel to CSV in Python Google Chrome API in Python Gaussian elimination in python Matrix List Comprehension in Python Python List Size Python data science course StandardScaler in Sklearn Python Redis Example Python Program for Tower of Hanoi Python Printf Style Formating Python Percentage Sign Python Parse Text File Python Parallel Processing Python Online Compiler Python maketrans() function Python Loop through a Dictionary Python for Data Analysis Python for Loop Increment Python Kwargs Example Python Line Break What does base case mean in recursion What does the if __name__ == "__main__" do in Python What is Sleeping Time in Python Kite Python Length of Tuple in Python Python String Lowercase Python Struct Python Support Python String Variable Python System Command Python TCP Server Python Unit Test Cheat String Python Validator Unicode to String in Python An Introduction to Mocking in Python An Introduction to Subprocess in Python with Examples Anytree Python API Requests using Python App Config Python Check if the directory exists in Python Managing Multiple Python Versions With pyenv os.rename() method in Python os.stat() method in Python Python Ways to find nth occurrence of substring in a string Python Breakpoint Find Last Occurrence of Substring using Python Python Operators Python Selectors Python Slice from Last Occurrence of K Sentiment Analysis using NLTK String indices must be integers in Python Tensorflow Angular in Python AES CTR Python Crash Course on Python by Google Curdir Python Exrex Python FOO in Python Get Bounding Box Co-ordinates Python Hog Descriptor Opencv Python Important Difference between Python 2.x and Python 3.x with Example Io stringio Python iobase Python IPython Display Iterate through the list in Python Joint Plot in Python JWT Decode Python List Comprehension in Python List in Python Map Syntax in Python Python Marshmallow PyShark in Python Python Banner Python Logging Maxbytes Python Multiprocessing Processor Python Skyline Python Subprocess Call Example Python Sys Stdout Python Win32 Process Python's Qstandarditemmodel Struct Module in Python Sys Module in Python Tuple in Python Uint8 Python XXhash Python Examples XXhash Python Handling missing keys in Python dictionaries Python Num2words Python Os sep OSError in Python Periodogram in Python Pltpcolor in Python Poolmanager in Python Python pycountry Python pynmea2 Difference between Package and Module in Python How to add 2 lists in Python How to assign values to variables in Python and other languages How to build an Auto Clicker using Python How to check if the dictionary is empty in Python How to check the version of the Python Interpreter How to convert Float to Int in Python How to Convert Int to String in Python How to Define a Function in Python How to Install Pandas in Python How to Plot Graphs Using Python How to Program in Python on Raspberry pi How to Reverse a number in Python How to Sort a String in Python What is Collaborative Filtering in ML, Python What is the Python Global Interpreter Lock

YOLO Python

YOLO means you only look once.It is a technique to perform object detection is called YOLO. It is the algorithmused by the program to identify items in the image.

Earlier detection frameworks use image classification techniques to find objects while looking at various areas of the image regularly at various scales. This technique is inaccurate and slow.

YOLO uses a completely different technique. It simply takes a single look at the full image and scans the network once to find items. Thus, it moves fast.

YOLO uses faster R-CNN and SSD for object detection frameworks.

OpenCV dnn module:

The DNN (Deep Neural Network) module was first included in the opencvcontrib repository. Users may now perform inference on pre-trained deep learning models inside of OpenCV due to its relocation to the master branch of the opencv.

In beginning only Caffe and Torch models were supported. Over the period support for different frameworks like TensorFlow is being added.

Yolo has recently been added. To identify common objects, we use the OpenCV dnn module with a pre-trained YOLO model.

Python Program

// python program
import cv2
import argparse
import numpy as a
// arguments
b = argparse.ArgumentParser()
b.add_argument('-i', '--image', required=True,
help = 'path to input image'’)
b.add_argument('-c', '--config', required=True,
help = 'pre-trained yolo approach’)
b.add_argument('-w', '--weights', required=True,
help = 'how to get to yolo trained weights’)
b.add_argument('-cl', '--classes', required=True,
help = 'path to a text file where class names are located’)
args = b.parse_args()

We require these things to execute the code:

  1. Python 3: If you are installed python already then run it and it verify whether it installed or not. Run python3 in command prompt.
  2. Numpy: pip install numpy

    numpy should install pip. Make pip linked to python3.
  3. OpenCV-python: For image processing and computer vision tasks, OpenCV is a good tool. This open-source library can be used to carry out operations including face detection, object tracking, and landmark detection.

Command Line Arguments

There are four input arguments.

  • Text file containing class names.
  • YOLO config file.
  • Pre-trained YOLO weights.
  • Input image.

Input image was our choice.

Run the program by typing.

$ python yolo_opencv.py --image dog.jpg --config yolov3.cfg --weights yolov3.weights --classes yolov3.txt

Reading input

image = cv2.imread(args.image)

Width = image.shape[1]

Height = image.shape[0]

scale = 0.00392

//class names were read from a text file

classes = None

with open(args.classes, 'r') as f:

classes = [line.strip() for line in f.readlines()]

// generate different colors for different classes

COLORS = a.random.uniform(0, 255, size=(len(classes), 3))

// read pre-trained model and configuration file

z = cv2.dnn.readz(args.weights, args.configuration)

blob = cv2.dnn.blobFromImage(image, scale, (416,416), (0,0,0), True, crop=False)

z.setInput(blob)

read the input image and get it height and width.

Extract the class names to a list from the text file that provides them in human readable form.

Create different colors for different classes.

z = cv2.dnn.readNet(args.weights, args.config)

above command reads the config file and weights.

blob = cv2.dnn.blobFromImage(image, scale, (Width,Height), (0,0,0), True, crop=False)

z.setInput(blob)

Output layer and bounding box

def get_result_layers(z):

layer_names = z.getLayerNames()

result_layers = [layer_names[i[0] - 1] for i in z.getUnconnectedOutLayers()]

return result_layers

// function to draw bounding box on the detected object with class name

def draw_bounding_box(img, class_id, confidence, i, j, i_plus_w, j_plus_h):

 label = str(classes[class_id])

color = COLORS[class_id]

 cv2.rectangle(img, (i,j), (i_plus_w,j_plus_h), color, 2)

cv2.putText(img, label, (x-10,y-10) cv2.FONT_HERSHEY_SIMPLEX, 0.5, color, 2)

In a sequential CNN network, the final output layer will usually be the only one. We are using the YOLO v3 architecture, which has numerous output layers that provide predictions. The names of the output layers are provided by the get output layers() method. There is no next layer connected to an output layer.

The function draw bounding box() draws a rectangle across the specified expected region and identifies the class over the box. We can also write the confidence value if necessary.

Running interface

class_ids = []

confidences = []

boxes = []

conf_threshold = 0.5

nms_threshold = 0.4

// Get the confidence, class ID, and bounding box parameters for each detection made by each output layer, and reject poor detections.

 (confidence < 0.5)

for out in outs:

for detection in out:

scores = detection[5:]

class_id = a.argmax(scores)

confidence = scores[class_id]

if confidence > 0.5:

center_i = int(detection[0] * Width)

center_j = int(detection[1] * Height)

w = int(detection[2] * Width)

h = int(detection[3] * Height)

x = center_i - w / 2

y = center_j - h / 2

class_ids.append(class_id)

confidences.append(float(confidence))

boxes.append([i, j, w, h])

outs = net.forward(get_output_layers(net))

The network receives the identical feed forward as it happens above line. If we don't specify the names of the output layer, it will only deliver predictions from the last output layer by default. Any additional output layer won't be taken into account.

For each detection from each output layer, the class id, confidence, and bounding box corners must be obtained. More importantly, the weak detections must be disregarded (detections with low confidence value).

Non-max suppression

indices = cv2.dnn.NMSBoxes(boxes, confidences, conf_threshold, nms_threshold)

//after nms, go through the remaining detections and construct a bounding box.

for n in indices:

n = n[0]

box = boxes[n]

i = box[0]

j = box[1]

w = box[2]

h = box[3]

draw_bounding_box(image, class_ids[i], confidences[i], round(x), round(y), round(x+w), round(y+h))

cv2.imshow("object detection", image)

cv2.waitKey()

cv2.imwrite("object-detection.jpg", image)

cv2.destroyAllWindows()

Even though we rejected weak detections, there will be several duplicate detections with overlapping bounding boxes. Non-max suppression is used to produce high overlapping box deletion.

YOLO Python

Output of the program using few images:

YOLO Python YOLO Python YOLO Python