Python Opencv Create Video From Images

Compile OpenCV 4. 4 ? How to pass image to neural network ? and How to make a prediction with MobileNet or dnn module in OpenCV?. virtualenvs” in the highlighted paths as shown in below image. I was looking into making a short video based on images produced with matplotlib or pygame. You start by drawing a rectangle around the foreground image. Welcome to a tutorial series, covering OpenCV, which is an image and video processing library with bindings in C++, C, Python, and Java. Well, it stands for ‘Open Source Computer Vision Library’ initiated by some enthusiast coders in Z1999 to incorporate Image Processing into a wide variety of coding languages. (py36) D:\python-opencv-sample>python asift. Tracking the movement of a finger is an important feature of many computer vision applications. (Open Source Computer Vision) 2. imread('messi5. Using OpenCV in Python is a very good solution to prototype vision applications, it allows you to quickly draft and test algorithms. 04 alongside Windows 10 (dual boot) How to create a beautiful pencil sketch effect with OpenCV and Python 12 advanced Git commands I wish my co-workers would know How to classify iris species using logistic regression. #Capture images per 25 frame. image already has a IO plugin system with very similar though slightly more complicated infrastructure, and in the future it may be wise to merge the two systems. The following article will help you to resizing the images in python using OpenCV. Now navigate to the new directory as follows:. Video Analysis using OpenCV-Python. The image format is chosen based on the filename extension (see imread() for the list of extensions). I was looking into making a short video based on images produced with matplotlib or pygame. In my last tutorial I’ve shown you how to create a minimal Tkinter application: load an image with OpenCV, plot the image on a Tkinter window and apply a blur filter when the user presses a button. We will learn how with few lines we can start to programmatically create videos using OpenCV with Python 3. python opencv. Set to capture images per how many frames. Well, it stands for ‘Open Source Computer Vision Library’ initiated by some enthusiast coders in Z1999 to incorporate Image Processing into a wide variety of coding languages. Reading a Video. Images and OpenCV. 9 thoughts on “ Extracting and Saving Video Frames using OpenCV-Python ” Anonymous 27 Apr 2019 at 9:45 pm. Create OpenCV Image Classifiers Using Python: Haar classifiers in python and opencv is rather tricky but easy task. This tutorial is a practice session of learning video processing using web camera in a laptop. So, Our GoalIn this session, 1. My environment is pycharm 2018. js in a browser window while using WebSockets to join this all together. How to de-noise images in Python How to create a cool cartoon effect with OpenCV and Python How to install Ubuntu 16. Writing to video with OpenCV. second argument is our image. pip3 install opencv-python. openCV is the computer vision library specially designed for c++ and later on ported to python support also. As these are pre-trained in OpenCV, their learned knowledge files also come bundled with OpenCV opencv/data/. You will use powerful machine learning tools such as OpenCV, Dlib, and TensorFlow to build exciting projects such as classifying handwritten digits, detecting facial features,and much more. OpenCV is a free open source library used in real-time image processing. We’ll use two of the biggest, most exciting image processing libraries available for Python 3, Dlib and OpenCV. 0-dev to get an access for non free modules can be a headache for some people especially on Windows machine. Using PIL library we are opening images and resizing them to their mean_height and mean_width because the video which. In these files in particular how to parse the information on the video, how to save/load pictures using FFMPEG, etc. GitHub Gist: instantly share code, notes, and snippets. You can create as many windows as you wish, but with different window names. I haven’t done too much other than searching Google but it seems as if “imager” and “videoplayR” provide a lot of the functionality but not all of it. Here is the results with a simple simulation used once in while in my teachings. virtualenvs” in the highlighted paths as shown in below image. # Create an output movie file (make sure resolution/frame rate matches input video!) # So we capture a video, process it frame-by-frame and we want to save that video, it only possible by using " VideoWriter " object # FourCC is a 4-byte code used to specify the video codec. Either resulting from this tutorial: Read and write video frames in Python using FFMPEG - __del__( self ) or from some code elsewhere, and you are willing to use an alternative to ffmpeg to convert your PIL images to a video format like in this case: python - Piped FFMPEG won't write frames correctly - Stack Overflow, then read on. Image Processing with Python Desert Py Meetup OpenCV-Python is the Python API of OpenCV Color image loaded by OpenCV is in BGR mode. py; Test the model python recognize_video. we have been using an "onboard computer" to do our image processing and have sent the packets to the C-RIO. py # Saves image of the current frame. First argument is a window name which is a string. I am using opencv 2. I started the process off by working through and validating each step I wanted to perform, beginning with standard imports and reading in the sample image. After few stackoverflow answers, I got a way to slice the Mat image. Cheat sheets and many video examples and tutorials step by step. Aside from the beginning lines, handling frames from a video is identical to handling for images. 1 with CodeBlocks IDE on Ubuntu 11. The OpenCV library provides us a greatly interesting demonstration for a face detection. Converting an image to black and white with OpenCV can be done with a simple binary thresholding operation. Download the video via this link. We will then display the video on a OpenCV window. We can use VideoCapture object to get video frames and images. Create Negative or Invert Image using OpenCV Python This post will be helpful in learning OpenCV using Python programming. • Core Operations In this section you will learn basic operations on image like pixel editing,. Using OpenCV to input a video file and to read each frame then save it to a image file with a Python script. PRAKASH said Thanks for this article. when I run the code and play the video, the video plays with proper FPS (same speed as just opening it with winows media player), however, the video window is small. Using input from mounted camera behavior of robot is controlled. Create advanced applications with Python and OpenCV, exploring the potential of facial recognition, machine learning, deep learning, web computing and augmented reality. This tutorial is a practice session of learning video processing using web camera in a laptop. It provides a wide sense of image processing. I tried it in both command line interpreter and also pycharm IDE. Just a simple task to get started. This step is also called. After flying this past weekend (together with Gabriel and Leandro) with Gabriel’s drone (which is an handmade APM 2. Resizing an image can be done in many. Tutorial 7- Change Brightness & Contrast of an image OpenCv C++. It seems that the interpreter can't find the default images. py, and create test data to detect and recognize my faces. Used as a. Now, let us create a virtual environment with conda. imshow() to display an image in a window. This could have been really easy in Python as numpy is really easy to slice. If you need support or have any comments, you can do it right now. In this tutorial, you will learn how to create animated GIFs using OpenCV, Python, and ImageMagick. Color trackbar/slider using OpenCV Python By the end of this post, you’ll have made a pretty basic HSV color trackbar/slider that filters out a range of colors, leaving you with the range of colors that you want to identify. It contains a large collection of image processing functions. Take a video as. PRAKASH said Thanks for this article. Python OpenCV cv2. Connect a Webcam to your PC. IT was designed for computational efficiency and with a strong focus on real-time applications, video and image processing. Introduction. After a short description of OpenCV, we will see the steps needed to produce a model file using the OpenCV Cascade Classifier. Python is a great programming language to work with the webcam. Using this library, you can capture and record webcam video as well as working with videos too. How to use the output from OpenCV selectROI to make a copy of an area of an image I'm selecting a part of an image using cv2. Combine images into a video with Python 3 and OpenCv 3. In this tutorial we will learn how to convert an image to black and white, using Python and OpenCV. Python and Java. First we prepare the environment, if you have experience with Python programming this. Resizing an image means change the dimensions of the image change either width of it or height of it or both at the same time. # Create an output movie file (make sure resolution/frame rate matches input video!) # So we capture a video, process it frame-by-frame and we want to save that video, it only possible by using " VideoWriter " object # FourCC is a 4-byte code used to specify the video codec. You need to create a subdirectory called “images”. Just a simple task to get started. 4 opencv, 3. We'll discuss how to: Access a video stream, using either a builtin/USB webcam or the Raspberry Pi camera module. Skin Detection Using OpenCV Python. It's used into Image Processing, Machine Learning and Computer Vision in the area of AI. Let us look how to prepare a sample Python application to stream the camera using OpenCV. I have to face many difficult situations when I configure OpenCV on Windows 7 using Visual Studio 2012, install Python to run the script crop_face. Cheat sheets and many video examples and tutorials step by step. 04 alongside Windows 10 (dual boot) How to create a beautiful pencil sketch effect with OpenCV and Python 12 advanced Git commands I wish my co-workers would know How to classify iris species using logistic regression. In many image processing based robotics applications, a camera is mounted in robot. Tutorial 3 - Create a Image OpenCV C++ Today I'm going to show you how to create image using OpenCv. Using the code snippets included, you can easily setup a Raspberry Pi and webcam to make a portable image sensor for object detection. 04 alongside Windows 10 (dual boot) How to create a beautiful pencil sketch effect with OpenCV and Python 12 advanced Git commands I wish my co-workers would know OpenCV with Python Blueprints: Holiday Sale. A trendy thing to do is create a mirror image of a picture and then fade it to white using some application software. Using this library, you can capture and record webcam video as well as working with videos too. In current scenario, techniques such as image scanning, face recognition can be accomplished using OpenCV. She showed that using video alone, it is possible to positively identify a train based on motion from frame to frame. OpenCV 3 Tutorial image & video processing Installing on Ubuntu 13 Mat(rix) object (Image Container) Creating Mat objects The core : Image - load, convert, and save Smoothing Filters A - Average, Gaussian Smoothing Filters B - Median, Bilateral OpenCV 3 image and video processing with Python OpenCV 3 with Python Image - OpenCV BGR : Matplotlib RGB. you can use skvideo library to create video form sequence of images. You will use powerful machine learning tools such as OpenCV, Dlib, and TensorFlow to build exciting projects such as classifying handwritten digits, detecting facial features,and much more. To capture a video, you need to create a VideoCapture object. Writing to video with OpenCV. We can use VideoCapture object to get video frames and images. Using OpenCV in Python is a very good solution to prototype vision applications, it allows you to quickly draft and test algorithms. Explore Opencv Openings in your desired locations Now!. For those who’d like a video walkthrough, this entire post is also available as a walkthrough on YouTube. We will learn how with few lines we can start to programmatically create videos using OpenCV with Python 3. Learn about GPU, CPU, installing OpenCV with Python wrappers, Introduction to Computer Vision With OpenCV and Python search all orange pixels in an image (like the marker in our demo video). This will require two tiers of backends one for visualization and one for processing. use_backend("opencv") use_backend(scikits. Finding blocks of text in an image using Python, OpenCV and numpy As part of an ongoing project with the New York Public Library, I’ve been attempting to OCR the text on the back of the Milstein Collection images. You can operate the HSV (Hue, Saturation, Value) sliders to isolate the colour you want to detect in the image. After flying this past weekend (together with Gabriel and Leandro) with Gabriel’s drone (which is an handmade APM 2. It's used into Image Processing, Machine Learning and Computer Vision in the area of AI. OpenCV 강좌 C++ & Python - 사각형 그리는 rectangle 함수 사용법 OpenCV/OpenCV C++&Python 강좌 2019. Create a Python script to control Webcam. Perone / 26 Comments The new generation of OpenCV bindings for Python is getting better and better with the hard work of the community. Its argument can be either the device index or the name of the video file to be read. The window automatically ts to the image size. You need to create a subdirectory called “images”. In this OpenCV with Python tutorial, we're going to cover some basic operations with video and webcams. Converting an image to black and white with OpenCV can be done with a simple binary thresholding operation. Using OpenCV to input a video file and to read each frame then save it to a image file with a Python script. NOTE: I MADE THIS PROJECT FOR SENSOR CONTEST AND I USED CAMERA AS A SENSOR TO TRACK AND RECOGNITION FACES. Using PIL library we are opening images and resizing them to their mean_height and mean_width because the video which. Python is a widely used general-purpose, high-level programming language. What is Skin Detection? Process of finding skin-colored pixels and regions in an image or a video. The following sample OpenCV python code explain how to open the device video node, set the resolution, grab the frame and then display the frame in preview window. OpenCV-Python Tutorials Documentation Release 1. OpenCV has been a vital part in the development of software for a long time. 0-dev for Python2 on Windows using CMake and Visual Studio Remarks Building and Compiling opencv 3. Notice: the total frame count of video captured by opencv often is not correct. jpg',0) However, what I got is NoneType. Homography RANSAC. Learning OpenCV is a good asset to the developer to improve aspects of coding and also helps in building a software development career. There you provide some nice touchups specifying this area is background, this area is foreground etc. It implements algorithms and utilities for use. OpenCV provides some basic methods to access the. imread("kids. The function imwrite saves the image to the specified file. PhD, Author, Entrepreneur. imshow() to display an image in a window. In many image processing based robotics applications, a camera is mounted in robot. Introduction In this tutorial we will learn how to obtain video from a webcam, using Python and OpenCV. Opencv tutorials tips and tricks. scikit-image. As these are pre-trained in OpenCV, their learned knowledge files also come bundled with OpenCV opencv/data/. Reading a Video. GitHub Gist: instantly share code, notes, and snippets. Capture Video from Camera. To avoid conflicts between different versions of our libraries, you can create a virtual environment using venv to separate them. Hey, so I'm working on a project for which I need to be able to continuously stream video to/from a hard drive (I'll be using an SSD). we have been using an "onboard computer" to do our image processing and have sent the packets to the C-RIO. Let’s capture a video from the camera (I am using the in-built webcam of my laptop), convert it into grayscale video and display it. Using PIL library we are opening images and resizing them to their mean_height and mean_width because the video which. Create Face Detection Software; Detect Objects, including corner, edge, and grid detection techniques with OpenCV and Python; Use Python and Deep Learning to build image classifiers; Use Python and OpenCV to draw shapes on images and videos; Create Color Histograms with OpenCV; Study from MIT notes and get Interview questions. python extract_embeddings. OpenCV is used for a very wide range of applications including medical image analysis, stitching street view images, surveillance video, detecting and recognizing faces, tracking moving objects, extracting 3D models and much more. scikit-image is an open source Python package that works with NumPy arrays. PhD, Author, Entrepreneur. Image and Video Processing in Python. Again segment the image to get very nice results. 1 python interpreter, anaconda 3. Its argument can be either the device index or the name of the video file to be read. second argument is our image. The first step towards reading a video file is to create a VideoCapture object. OpenCV is a library full of great easy-to-use algorithms that can be used in 3D modeling, advanced image & video editing, tracking an identifying objects in videos, classifying people who are doing a certain action in videos, finding similar images from a dataset of images, and much more. opencv) Scikits. PhD, Author, Entrepreneur. Opencv Python image processing based tutorial, to turn from the network, the main Python for image enhancement, transformation, matching, contour, video processing, segmentation, tracking, projection and so on Key Technologies of the primary tutorial. OpenCv library can be used to perform multiple operations on videos. Introduction to Pandas with Practical Examples (New) Main Book. OpenCV provides a very simple interface to this. image already has a IO plugin system with very similar though slightly more complicated infrastructure, and in the future it may be wise to merge the two systems. Create OpenCV Image Classifiers Using Python: Haar classifiers in python and opencv is rather tricky but easy task. It has C++, C, and Python. Second argument is our image. imread('C:\\Users\\Link\\Desktop\\image. You can find a python sample at OpenCV source at this link. Create a project folder. Aside from the beginning lines, handling frames from a video is identical to handling for images. py; Test the model python recognize_video. Included is a sample node that can be used as a template for your own node. In current scenario, techniques such as image scanning, face recognition can be accomplished using OpenCV. Tutorial 7- Change Brightness & Contrast of an image OpenCv C++. Python is a widely used general-purpose, high-level programming language. Data Analysis with Pandas. That’s why I output images and use some other software to convert them a video file. imread("kids. py; Prerequisites. I write about #DeepLearning, #ComputerVision, and #Python over at https://t. The function imwrite saves the image to the specified file. OpenCV is the de-facto standard C/C++ library for image and vision processing extensively used by computer vision community to create desktop and embedded applications. Simple wrapper for opencv-python. Notice: the total frame count of video captured by opencv often is not correct. The purpose of this tutorial is to learn how to write frames to video using OpenCV and Python. And perhaps the best way to find LOLs is from memes. In this OpenCV with Python tutorial, we're going to cover some basic operations with video and webcams. Notice: the total frame count of video captured by opencv often is not correct. What is Skin Detection? Process of finding skin-colored pixels and regions in an image or a video. In this blog, we will do a small project using OpenCV-Python where we will be creating video from image sequences. OpenCV is used for a very wide range of applications including medical image analysis, stitching street view images, surveillance video, detecting and recognizing faces, tracking moving objects, extracting 3D models and much more. Again segment the image to get very nice results. import numpy as np import cv2 # Load an color image in grayscale img = cv2. Welcome to a tutorial series, covering OpenCV, which is an image and video processing library with bindings in C++, C, Python, and Java. First argument is a window name which is a string. And perhaps the best way to find LOLs is from memes. In this post, I will share how to create a Python extension that lists camera devices for OpenCV-Python on Windows. In this post we will access the camera of laptop or any webcam using opencv and produce live video stream. py; Train the SVM model python train_model. The image format is chosen based on the filename extension (see imread() for the list of extensions). Images and OpenCV. Tutorial 7- Change Brightness & Contrast of an image OpenCv C++. This technique is a specific use case of object detection system that deals with detecting instances of semantic objects of a certain class (such as humans, buildings or cars) in digital images and videos. Algorithm then segments the image. Splitting Video Into Images with OpenCV and Python Keith, the Coder OpenCV with. You'll learn state-of-the-art techniques for classifying images, finding and identifying human postures, and detecting faces within videos. py; Test the model python recognize_video. OpenCv library can be used to perform multiple operations on videos. 0-dev for Python2 on Windows using CMake and Visual Studio Remarks Building and Compiling opencv 3. Again segment the image to get very nice results. In my last tutorial I’ve shown you how to create a minimal Tkinter application: load an image with OpenCV, plot the image on a Tkinter window and apply a blur filter when the user presses a button. The window automatically fits to the image size. Ask Question OpenCV fails to create video from images. Includes all OpenCV Image Processing Features with Simple Examples. shape # Get some stats on the image file to create the video with video = cv2. scikit-image is an open source Python package that works with NumPy arrays. Notice: the total frame count of video captured by opencv often is not correct. Aside from the beginning lines, handling frames from a video is identical to handling for. Let's see how to find contours of a binary image:. You can operate the HSV (Hue, Saturation, Value) sliders to isolate the colour you want to detect in the image. One of the challenges in detecting fingers is differentiating a hand from the background and identifying the tip of a finger. Creating Image. To use DirectShow APIs, read the Microsoft’s tutorial – Selecting a Capture Device, which shares how to list video and audio devices in C++. A Beginner Guide to Python Get Video Duration with OpenCV – Python Tutorial. scikit-image. Develop your computer vision skills by mastering algorithms in Open Source Computer Vision 4 (OpenCV 4)and Python. Finding the distance from your camera to object/marker using Python and OpenCV. Let us look how to prepare a sample Python application to stream the camera using OpenCV. This project is entirely based on what we read in Chapter 1 and 2. start-video-stream-w-opencv. VideoCapture(video_path) cv2. OpenCV is a popular library available for Python that can make it easier to work with videos and webcam. Extracting a ROI (Region of Interest) using OpenCV and Python is not so hard as it could may sound. Splitting Video Into Images with OpenCV and Python Keith, the Coder OpenCV with. That’s why I output images and use some other software to convert them a video file. We'll discuss how to: Access a video stream, using either a builtin/USB webcam or the Raspberry Pi camera module. The Tools of Face Detection in Python. Both of these classifiers process images in gray scales, basically because we don't need color information to decide if a picture has a face or not (we'll talk more about this later on). We’ll use two of the biggest, most exciting image processing libraries available for Python 3, Dlib and OpenCV. 3 with Python 3 from a Jupyter Notebook within a Docker container; Perform simple Computer Vision tasks using manipulation techniques; Build Instagram-style image filters; Adjust brightness, saturation, and image hue to create Instagram-style filters; Bulk-apply image manipulation operations to a folder of images. Create Face Detection Software; Detect Objects, including corner, edge, and grid detection techniques with OpenCV and Python; Use Python and Deep Learning to build image classifiers; Use Python and OpenCV to draw shapes on images and videos; Create Color Histograms with OpenCV; Study from MIT notes and get Interview questions. This will require two tiers of backends one for visualization and one for processing. A popular computer vision library written in C/C++ with bindings for Python, OpenCV provides easy ways of manipulating color spaces. The first step towards reading a video file is to create a VideoCapture object. Motion detection using OpenCV. I thought this would be a good chance for me to do a little image manipulation in Python, so I fired up my IPython notebook and make use of OpenCV. Slice a Mat Image: Mat img; Rect rect; /* Get the img from webcam or from file. Here I will show how to implement OpenCV functions and apply them in various aspects using some great examples. Opencv Python image processing based tutorial, to turn from the network, the main Python for image enhancement, transformation, matching, contour, video processing, segmentation, tracking, projection and so on Key Technologies of the primary tutorial. Let’s try to do something interesting using CV2. Source image: So, we begin to import our modules and the source image: import cv2 import numpy as np #import image image = cv2. I was looking into making a short video based on images produced with matplotlib or pygame. Camera Pi is an excellent add-on for Raspberry Pi, to take pictures and record quality videos. Let's start. Includes all OpenCV Image Processing Features with Simple Examples. To make objects recognizable in pictures, we need to process the photo with Illumination Compensation. The following article will help you to resizing the images in python using OpenCV. com, India's No. Python OpenCV For FRC Teams. Only 8-bit (or 16-bit unsigned (CV_16U) in case of PNG, JPEG 2000, and TIFF) single-channel or 3-channel (with ‘BGR’ channel order) images can be saved using this function. To extract red channel of image, we will first read the color image using cv2 and then extract the red channel 2D array from the image array. The function imwrite saves the image to the specified file. the best solutio is to create your own classifier. We will learn how with few lines we can start to programmatically create videos using OpenCV with Python 3. In many image processing based robotics applications, a camera is mounted in robot. So here's my problem: I need a GUI to get a live webcam stream from openCV (or just open a video file), pass it to the Tkinter GUI window, and add some buttons and stuff to it. 9 thoughts on “ Extracting and Saving Video Frames using OpenCV-Python ” Anonymous 27 Apr 2019 at 9:45 pm. pip3 install opencv-python. second argument is our image. It provides a wide sense of image processing. Simple wrapper for opencv-python. What is Skin Detection? Process of finding skin-colored pixels and regions in an image or a video. OpenCV provides a very simple interface to this. You can find the video walkthrough at the end of this page. Here I will show how to implement OpenCV functions and apply them in various aspects using some great examples. import numpy as np import cv2 # Load an color image in grayscale img = cv2. Capture Video from Camera. Extract facial embeddings. virtualenvs” in the highlighted paths as shown in below image. Face Detection in R. Create OpenCV Image Classifiers Using Python: Haar classifiers in python and opencv is rather tricky but easy task. In this tutorial we will learn how to obtain video from a webcam, using Python and OpenCV. We can use VideoCapture object to get video frames and images. The function imwrite saves the image to the specified file. In this tutorial, we will show how to install OpenCV on CentOS 7. As we know OpenCV is a widely used library for image processing. Filter Images and Videos The image filtering is a neighborhood operation in which the value of any given pixel in the output image is determined by applying a certain algorithm to the pixel values in the vicinity of the corresponding input pixel. Image analysis intro using python & opencv. 04 alongside Windows 10 (dual boot) How to create a beautiful pencil sketch effect with OpenCV and Python 12 advanced Git commands I wish my co-workers would know OpenCV with Python Blueprints: Holiday Sale. And next up is to create the actual OpenCV video handling capability. Again segment the image to get very nice results. Source image: So, we begin to import our modules and the source image: import cv2 import numpy as np #import image image = cv2. Create a Word Counter in Python. My environment is pycharm 2018. The window automatically fits to the image size. Download the video via this link. Welcome to a tutorial series, covering OpenCV, which is an image and video processing library with bindings in C++, C, Python, and Java. I would be able to run the IplImage to Mat conversion but I am getting problem with mat to IplImage program I am running the following code in VS 2008 using OpenCV 2. Tracking the movement of a finger is an important feature of many computer vision applications. Python - Using OpenCV how to stick. use_backend("opencv") use_backend(scikits. Deep Learning Face Detection, Face Recognition & OCR. We are not interested in the details of the image but in the shape of the object to track. In this tutorial, we will show how to install OpenCV on CentOS 7. You'll then combine all of these techniques to build a meme generator with OpenCV! We all need a good laugh every now and then. you can use skvideo library to create video form sequence of images. Getting Started with OpenCV and Python: Featuring The Martian If you’re curious to find out how to launch yourself into outer space and land on Mars, you’ve come to the right place. While the original implementation is based on SIFT, you can try to use SURF or ORB detectors instead. Python provides lots of libraries for image processing, including − OpenCV − Image processing library mainly focused on real-time computer vision with application in wide-range of areas like 2D and 3D feature toolkits, facial & gesture recognition, Human-computer interaction, Mobile robotics, Object identification and others. After a short description of OpenCV, we will see the steps needed to produce a model file using the OpenCV Cascade Classifier. There is also no support for the OpenCV classes like Rect, Point etc. The function imwrite saves the image to the specified file. In image processing tools, for example: in OpenCV, many functions uses gray scale images before processing and this is done because it simplifies the image, acting almost as a noise reduction and increasing processing time as there’s less information in the images.