OpenCV convert binary image to BGR

Python OpenCV: Converting an image to black and white

For a detailed explanation on how to convert an image to gray scale using OpenCV, please check here. So, as first input of the cvtColor, we will pass the original image. As second input we need to pass the color space conversion code. Since OpenCV uses the BGR color space when reading an image, we need to use the COLOR_BGR2GRAY conversion code It can process images and videos to identify objects, faces, or even the handwriting of a human. In this article, we will convert a BGR image to RGB with python and OpenCV. OpenCV uses BGR image format. So, when we read an image using cv2.imread() it interprets in BGR format by default I got that right, that I should only have two different values in binary images, right? I'm starting to question my understanding of the matter flohei ( 2012-11-22 18:24:55 -0500 ) edi OpenCV - Convert Colored Image to Binary Image. At times, you may need to convert an image to a binary image. In other words, you need to convert a color image or greyscale image to black and white image. In this tutorial, we shall learn how to convert an image from color to black and white OpenCV C++ Server Side Programming Programming. Inverting a binary image means inverting the pixel values. From a visual perspective, when we invert a binary image, white pixels will be converted to black, and black pixels will be converted to white. The basic form of this function is −. cvtColor (original_image, grayscale_image, COLOR_BGR2GRAY)

Convert BGR and RGB with OpenCV function cvtColor () Various color spaces such as RGB, BGR, HSV can be mutually converted using OpenCV function cvtColor (). dst = cv2.cvtColor(src, code) Refer to the following document for the value to be specified for the parameter code. OpenCV: Miscellaneous Image Transformations Next, we call the cvtColor() function with COLOR_BGR2GRAY in order to convert from BGR color space (the default in OpenCV for color images) to grayscale. There are several enum values, which convert from colorful image to grayscale. You have the option to convert from grayscale to RGB/BGR, but as I mentioned above, this will not colorize the image

Converts an image from one color space to another. The function converts an input image from one color space to another. In case of a transformation to-from RGB color space, the order of the channels should be specified explicitly (RGB or BGR). Note that the default color format in OpenCV is often referred to as RGB but it is actually BGR (the. OpenCV use BGR not RGB, so if you fix the ordering it should work, though your image will still be gray. Solution 4: Alternatively, cv2.merge() can be used to turn a single channel binary mask layer into a three channel color image by merging the same layer together as the blue, green, and red layers of the new image Image Thresholding. Learn to convert images to binary images using global thresholding, Adaptive thresholding, Otsu's binarization etc. Smoothing Images. Learn to blur the images, filter the images with custom kernels etc. Morphological Transformations. Learn about morphological transformations like Erosion, Dilation, Opening, Closing etc.

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You can always do the following if you wish to keep the original image. C#. Copy Code. Image<Gray,Byte> Binary_Image = img.ThresholdBinary ( new Gray (threshold_value), new Gray ( 255 )); If you want to play with things a little you can add a trackbar to your form put the minimum to 0 and maximum to 255 and use this code. C# Note that when saving an image with the OpenCV function cv2.imwrite(), it is necessary to set the color sequence to BGR.. Convert BGR and RGB with Python, OpenCV (cvtColor) So far, it has been processed based on the grayscale image, but it is also possible to process the color image like cv2.threshold() with the same idea as the above example.. Generate an empty ndarray and store each result.

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Convert BGR and RGB with Python - OpenCV - GeeksforGeek

RGB to Grayscale in Python + OpenCV RGB to Binary Image. To convert RGB image to Binary image, we have to the RGB image into Grayscale image first The function converts an input image from I420 color space to BGR. The conventional ranges for B, G, and R channel values are 0 to 255. Output image must be 8-bit unsigned 3-channel image. CV_8UC3. Width of BGR output image must be the same as width of input image. Height of BGR output image must be equal 2/3 from height of input image. Not

I am trying to convert a BGR Mat image to bytes string in C++. So that I can pass it to a python server (along with its spatial dimensions values) where I can reconstruct the image. The code I used is: //opencvimage is the Mat object (BGR image) string matAsString(opencvimage.begin<unsigned char>(), opencvimage.end<unsigned char>()); This however extracts only the first channel of the image (I. Convert BayerBG12Packed (12-Bit packed) into RGB. RGB vs. BGR. Result of cvtColor not displaying correctly for Lepoard Imaging USB 3.0 camera. In OpenCV , failed to create an RGB image from a Bayer binary file. [closed] How to convert from BGR to BayerRG. Android: Native Opencv - cvtColor segfault. cvtcolor function proble

How to create a binary image mat? - OpenCV Q&A Foru

  1. In the above code, we first convert binary image to Numpy array, then decode the array with cv2.imdecode().The final img is an OpenCV image in Numpy ndarray format.. PIL or OpenCV image to base64 PIL Image to base6
  2. This is a C++ program to convert BGR image to greyscale image using cvtColor function present in the OpenCV library in c++. Greyscale images are required for any functions in OpenCV also they are useful in distinguishing in intensity between the pixels as extra inforation is not required to be submitted. # include <opencv2/opencv.hpp>
  3. If set, return 16-bit/32-bit image when the input has the corresponding depth, otherwise convert it to 8-bit. If set, the image is read in any possible color format. If set, use the gdal driver for loading the image. If set, always convert image to the single channel grayscale image and the image size reduced 1/2
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Convert RGB to Binary Image in Python using OpenCV. Now I am going to show you how you can convert RGB to Binary Image or convert a colored image to black and white. Here we are just going to write a few lines of Python code and it will convert our RGB image into a binary image. To convert an RGB image into a binary type image, we need OpenCV 1. Create Mat object with help of input RGB data & its width and height 2.Convert RGB to Gray image using cvtColor API 3. convert Gray to Binary ( black and white)images using threshold API 4. convert back Binary to RGB image using cvtColor API . single channel data copied to all R , G and B channel data code Local Binary Pattern, also known as LBP, is a simple and grey-scale invariant texture descriptor measure for classification. In LBP, a binary code is generated at each pixel by thresholding it's neighbourhood pixels to either 0 or 1 based on the value of the centre pixel. The rule for finding LBP of an image is as follows: Set a pixel value.

Here are the examples of the csharp api class Emgu.CV.Image.Convert() taken from open source projects. By voting up you can indicate which examples are most useful and appropriate But in Binary Image, there are only two possible values. Binary images have different types of applications. For example, morphological transformation requires a binary image, object shape extraction from background requires a binary image, etc. Using OpenCV, we can freely convert an image into a binary image This videos shows you how to use OpenCV to convert a BGR image to HSL and HSV.Wikipedia Link: https://en.wikipedia.org/wiki/HSL_and_HSVImage Source: https://.. color - opencv python convert bgr to grayscale Opencv-Grayscale mode Vs gray color conversion (1) Note: This is not a duplicate , because the OP is aware that the image from cv2.imread is in BGR format (unlike the suggested duplicate question that assumed it was RGB hence the provided answers only address that issue Binary images are important when we wish to reduce the amount of information in the image and focus only on regions of the image we need. scale CV_BGR2HSV — For converting BGR images to HSV.

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Python Convert Image to Black and White (Binary) - Python

Problem: Convert image to binary opencv python . Have been trying to install the latest version of opencv-contrib-python package in the new Raspberry Pi (RPi 4) There are more than 150 color-space conversion methods available in OpenCV. But we will look into only two, which are most widely used ones: BGR Gray and BGR HSV. For color conversion, we use the function cv.cvtColor (input_image, flag) where flag determines the type of conversion. For BGR Gray conversion, we use the flag cv.COLOR_BGR2GRAY Now, let's see how we can correct it. We can use OpenCV's cv2.cvtColor() method to convert our BGR image format to RGB. This method changes the default BGR format of OpenCV to RGB format. The following is the code snippet to change the color format of the image from BGR to RGB Threshold respective to OpenCV Images: When handling images, we work with BGR/RGB colors, but sometimes finding the objects on the one-dimensional array (grayscale) is easier than working with three Dimensional arrays (BGR). When we are working with one-dimensional array/grayscale, at any given pixel will have 0 to 255 values only As we can see that the input image read by OpenCV is being shown as a BGR (Blue-Green-Red) image so we need to convert it to the RGB (Red-Green-Blue). #Converting to RGB img = cv2.cvtColor (img, cv2.COLOR_BGR2RGB) io.imshow (img) Step-3: Detecting edges. Here we are going to detect the edges in the image using adaptive thresholding methods

Now we know how to convert BGR image to HSV, we can use this to extract a colored object. In HSV, it is easier to represent a color than RGB color-space. In specifying the range, we have specified. A binary image is a monochromatic image that consists of pixels that can have one of exactly two colors, usually black and white. Binary images are also called bi-level or two-level. This means that each pixel is stored as a single bit—i.e., 0 or 1. The most important library needed for image processing in Python is OpenCV Then # threshold the alpha channel to create a binary mask. channels = cv2.split(img) mask = np.array(channels[3]) _, mask = cv2.threshold(mask, 250, 255, cv2.THRESH_BINARY) # Convert image and mask to grayscale or BGR based on input flag. if gray_flag: img = cv2.cvtColor(img, cv2.COLOR_BGRA2GRAY) else: img = cv2.cvtColor(img, cv2.COLOR.

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How to invert a binary image in OpenCV using C++

Welcome to the knowledge base portal - WWW.ONETOUCHBI.COM. It's the platform to connect all BI Associates under one umbrella.OpenCV Python Tutorial | Convert.. Introduction Sometimes, we may want an in-memory jpg or png image that is represented as binary data. But often, what we have got is image in OpenCV (Numpy ndarray) or PIL Image format. In this post, I will share how to convert Numpy image or PIL Image object to binary data without saving the underlying image to disk Next image shows the HSV cylinder. By SharkDderivative work: SharkD [CC BY-SA 3.0 or GFDL], via Wikimedia Commons Since colors in the RGB colorspace are coded using the three channels, it is more difficult to segment an object in the image based on its color

OpenCV offers the function cv::threshold to perform thresholding operations. We can effectuate types of Thresholding operations with this function. We will explain them in the following subsections. To illustrate how these thresholding processes work, let's consider that we have a source image with pixels with intensity values Since we are trying to go for color detection we will convert our RGB (or BGR in OpenCV) format image to HSV (Hue, Saturation, Value) color format as its much easier to manipulate colors in that model. This below script will let you use trackbars to adjust the hue, saturation, and value channels of the image Reads an image. Converts the image from BGR to gray. Saves the original image file. Creates the LUT as discussed previously. Applies the LUT over the image using the LUT() method. Saves the result of applying the LUT. The image is converted from BGR to gray using the cvtColor() method available in the Imgproc class. It accepts 3 arguments. Figure 3: Converting an image URL to OpenCV format with Python. Now, let's move on to the alternative method to downloading an image and converting it to OpenCV format. Method #2: scikit-image. The second method assumes that you have the scikit-image library installed on your system. Let's take a look at how we can leverage scikit-image to download an image from a URL and convert it to.

The default color format in OpenCV is generally said to as RGB but it is actually BGR (the bytes are reversed). So the first byte in a standard (24-bit) color image will be an 8-bit Blue component, the second byte will be Green, and the third byte will be Red Image processing is any form of processing for which the input is an image or a series of images or videos, such as photographs or frames of video. The output of image processing can be either an image or a set of characteristics or parameters related to the image. Open-CV. OpenCV is a free open source library used in real-time image processing. Emgu CV 3.x. Open CV 3.0 has been changed, the C interface that use IplImage has been slowly phased out and the C++ interface that utilize Mat is recommended in this release. In 3.0 release, Emgu CV has adapted to use the Mat class as a result. The Image<,> class is still available in this release for backward compatibility reason. If you are interest in using Image<,> class, you can checkout. At a high level, here is the 5-step process for contour detection in OpenCV: Read a color image. Convert the image to grayscale. Convert the image to binary (i.e. black and white only) using Otsu's method or a fixed threshold that you choose. If the objects in the image are black, and the background is white, we need to invert the image so. In this tutorial, you will learn to convert gray-scale image to binary image and negative image

Convert BGR and RGB with Python, OpenCV (cvtColor) note

RGB to Binary Color Conversion implemented on Python with OpenCV. There are two kind of solutions. The first is solution using the Open-CV's. library. The second is without the library. img_grayscale = cv2. cvtColor ( img, cv2. COLOR_BGR2GRAY) ( thresh, img_binary) = cv2. threshold ( img_grayscale, 128, 255, cv2. THRESH_BINARY | cv2 The color-corrected image is shown on the right side of Figure 1. We will use the RGB image as an example in the latter sections. But using RGB images is not a requisite — feel free to use the BGR image if you prefer. Make sure to pick the correct channels in operation. Resize Image. Quiz time: which OpenCV method should you use to resize an. In OpenCV, there are several colorspace conversions (more thant 150): RGB ↔ GRAY, RGB ↔ CIE, RGB ↔ YCrCb, RGB ↔ HSV, RGB ↔ HSL etc. But in this chapter, we'll be focused on the most widely used ones: BGR ↔ Gray and BGR ↔ HSV. To convert colorspace, we'll use cv2.cvtColor (input_image, flag) where flag determines the type of.

OpenCV: Color Conversion : Programming Tutorial

  1. OpenCVはBGR、PillowはRGB. カラー画像を読み込む場合、OpenCVのimread()では行(高さ) x 列(幅) x 色(3)のNumPy配列ndarrayとして読み込まれる。色の順番はBGR(青、緑、赤)。 関連記事: Python, OpenCVで画像ファイルの読み込み、保存(imread, imwrite) 画像を保存するOpenCVの関数imwrite()はBGRの順番を前提と.
  2. This function accepts two arguments: the actual image that we want the convert, followed by the output color space. Since OpenCV represents our image in BGR order rather than RGB, we specify the cv2.COLOR_BGR2HSV flag to indicate that we want to convert from BGR to HSV
  3. Introduction. In this tutorial we will learn how to obtain video from a webcam and convert it to black and white, using OpenCV and Python. For an explanation on how to get video from a web camera using OpenCV, please check here.. A very simple way of converting an image to black and white with OpenCV can be done with a binary thresholding operation. For a tutorial explaining how to convert an.
  4. I'm using the pytorch with float image (C++). Currently, I'm not using GPU, but I'm having difficulties to convert the data between torch and opencv. Basically, I'm reading an image, cv::Mat image, image_bgr; image_bgr = cv::imread(FILE..
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The function converts an input image from one color space to another. In case of a transformation to-from RGB color space, the order of the channels should be specified explicitly (RGB or BGR). Note that the default color format in OpenCV is often referred to as RGB but it is actually BGR (the bytes are reversed) Convertion from Image<Emgu.CV.Structure.Bgr, System.Single> to Image<Emgu.CV.Structure.Gray, System.Single> is not supported by OpenCV ,is it because the new version doesn't support the operating? and th The objective of this tutorial is to learn how to read an image and convert it to the HSV color space, using Python and OpenCV . Introduction. The objective of this tutorial is to learn how to read an image and convert it to the HSV color space, using Python and OpenCV.. The code shown below was tested using Python 3.7.2 and version 4.0.0 of OpenCV For better image operations convert RGB images to binary images. img_gray=cv2.cvtColor(img,cv2.COLOR_BGR2GRAY) converts image from 'rgb' format to 'gray' scale RGB to BGR converter. This tool is for converting from RGB to BGR online without damaging the quality of resultant image.Our RGB to BGR converter tool is free for use and very easy to use with a very good interface.Just select image from file selector or drag and drop image there and you will get result

Convert BGR and RGB with Python - OpenCV - GeeksforGeek . OpenCV uses BGR image format. So, when we read an image using cv2.imread it interprets in BGR format by default. We can use cvtColor method to convert a BGR image to RGB and vice-versa. Syntax: cv2.cvtColor (cod OpenCV is the huge open-source library for computer vision, machine learning, and image processing and now it plays a major role in real-time operation which is very important. Python OpenCV - Convert Image to Binary - To convert color or grey-scale image to binary image using these steps. 1. Read Image to Numpy Array. 2 Introduction. In this tip, we see how to do the conversion between Mat and BufferedImage. Mat is a data structure from OpenCV to process image.BufferedImage is a data structure from Java to store images.. Using the Code Convert Mat to BufferedImage . Mat data structure has image data, image type (GRAY, BGR), Height, Width.In mat2Img, the following function extracts meta data from Mat data.

OpenCV: Color Space Conversion

  1. OpenCV follows BGR order, while matplotlib likely follows RGB order. Therefore, when we display an image loaded in OpenCV using matplotlib functions, we may want to convert it into RGB mode. Source code looks like this: import cv2 import numpy as np import matplotlib.pyplot as plt bgr_img = cv2.imread ('images/san_francisco.jpg') b,g,r = cv2.
  2. OpenCV is used to read 3 Bands RGB image (meaning 3 channels). I want to convert a gray-scale image with shape (height,width) to a 3 channels image with shape (height,width,nchannels).The work is done with a for-loop, but there must be a neat way.Here is a piece code in program, can someone give a hint. Step 5: Contour to binary mask
  3. While converting a gray scale image to a binary image, we usually use cv2.threshold() and set a threshold value manually. Sometimes to get a decent result we opt for Otsu's binarization. I have a small hack I came across while reading some blog posts. Convert your color (RGB) image to gray scale. Obtain the median of the gray scale image
  4. It can process images and videos to identify objects, faces, or even the handwriting of a human. In this article, we will convert a BGR image to RGB with python and OpenCV. OpenCV uses BGR image format. So, when we read an image using cv2.imread () it interprets in BGR format by default. We can use cvtColor () method to convert a BGR image to.

create white binary image opencv; bgr to binary opencv; read image as binary opencv; black and white filter cv2; python opencv show black white image; python opencv convert to black and white; convert image to black and white in opencv python; convert image to black and white in opencv2 python; how to convert image to black and white in opencv. Method 1: Using imread () function. imread () function is used to read an image in OpenCV but there is one more parameter to be considerd, that is flag which decides the way image is read. There three flag defined in OpenCV.. So to convert the color image to grayscale we will be using cv2.imread (image-name.png,0) or you can also write cv2. Welcome back, Today Let's see how to create a binary image using OpenCV library. Before start, we should have a color image(RGB) or grayscale image to make it binary. For RGB images : RGB => Grayscale => Binary For Grayscale images : Grayscale => Binary Issue converting BGR image to RGB #12163. blake-edwards opened this issue on Aug 6, 2018 · 3 comments. Labels. bug category: imgproc. Milestone. 3.4.3. Comments. alalek added bug category: imgproc labels on Aug 7, 2018

A series of convenience functions to make basic image

How does one convert a grayscale image to RGB in OpenCV

RGB to Binary Image - OpenCV. GitHub Gist: instantly share code, notes, and snippets System information (version) OpenCV => 4.0.0 Operating System / Platform => Manjaro Linux 64 Bit Compiler => Python 3.7.1 Detailed description I have an image dataset stored as RGB images. I need to convert these RGB images to YUYV image.. The following is my code for reading images and converting them into binary format files in Ubuntu using Python + OpenCV. #coding=utf-8 ''' Created on March 24, 2016 Use OpenCV to read the image, save it as a binary format file, and then read the binary file and convert it into an image for display @author: hanchao ''' import cv2 import numpy. OpenCV provides cvtColor function that allows to convert an image from one color space to another. This function accepts color conversion code. BGR2GRAY code is used to convert RGB image to grayscale image. Note that, OpenCV loads an image where the order of the color channels is Blue, Green, Red (BGR) instead of RGB Image : Input image should be binary as Source, an 8-bit single-channel image. Non-zero pixels are treated as 1's. BGR image by using the OpenCV: Gray Scale image: We will convert the.

OpenCV: Image Processing in OpenC

The cvtColor() method of the Imgproc class changes/converts the color of the image from one to another. This method accepts three parameters −. src − A Matrix object representing source.. dst − A Matrix object representing the destination.. code − An integer value representing the color of the destination image.. To convert an HSV image to BGR you need to pass Imgproc.COLOR_HSV2BGR as. You can do that in Python/OpenCV by converting your blackAndWhiteImage to 3 channels, then use Numpy to change the color using the single channel blackAndWhiteImage as a mask. blackAndWhiteImage3 = cv 2 .cvtColor (blackAndWhiteImage, cv 2 .COLOR_GRAY 2 BGR) blackAndWhiteImage3 [blackAndWhiteImage== 0] = ( 0, 0, 255 ) numpy opencv python Numpy / OpenCV image BGR to RGB 1 October, 2019. Conversion between any/all of BGR, RGB, and GBR may be necessary when working with. Matplotlib pyplot.imshow(): M x N x 3 image, where last dimension is RGB.; OpenCV cv2.imshow(): M x N x 3 image, where last dimension is BGR; Scientific Cameras: some output M X N x 3 image, where last dimension is GBR; Note: as in any programming language. To do it, we need to call the cvtColor function, which allows to convert the image from a color space to another. As first input, this function receives the original image. As second input, it receives the color space conversion code. Since we want to convert our original image from the BGR color space to gray, we use the code COLOR_BGR2GRAY If set, always convert image to the 3 channel BGR color image and the image size reduced 1/8. Binary level PNG, 0 or 1, default is 0. the codecs shipped with an OpenCV image (libjpeg, libpng, libtiff, and libjasper) are used by default. So, OpenCV can always read JPEGs, PNGs, and TIFFs..

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Binarize image with Python, NumPy, OpenCV note

Image Color Space Conversion using Python and OpenCV by

  1. Python program to Split RGB and HSV values in an Image using OpenCV. I want to mention that, you should activate your python environment before running the file. In this code, we will be using two libraries: NumPy and OpenCV. Please note that in OpenCV BGR format is used instead of RGB. import numpy as np
  2. For example, if you have a typical three channel image with red, blue, and green components, there are six possible orderings. Most libraries use either RGB or BGR. Three (four) channel OpenCV types are expected to be in BGR(A) order. Map of Type to Numbers in OpenCV (data types x number of channels
  3. You can find the contours of various shapes, objects in an image using the findContours () method. This method accepts the following parameters −. A binary image. An empty list object of type MatOfPoint to store the contours. An empty Mat object to store the image topology. Two integer variables to specify the mode and method to find the.
  4. Libraries to use: [code]import cv2 import numpy as nm [/code]Now reading the image (though you have not asked this): * converting to gray scale during input : [code]img=cv2.imread('<image path>',0) [/code]The above line loads the image in gray sca..
  5. Overview of the image coordinate system in OpenCV. As I mentioned in Figure 1, an image is represented as a grid of pixels. Imagine our grid as a piece of graph paper. Using this graph paper, the point (0, 0) corresponds to the top-left corner of the image (i.e., the origin). As we move down and to the right, both the x and y-values increase

So, in the above application, I have converted the color space of original image of the video from BGR to HSV image. HSV color space is also consists of 3 matrices, HUE, SATURATION and VALUE. In OpenCV, value range for HUE, SATURATION and VALUE are respectively 0-179, 0-255 and 0-255 The first thing that must have come to your mind will why converting image from BGR to RGB. I have explained this thing in another article lets see it here again. OpenCV and matplotlib use a different order of primary channels. Whereas OpenCV reads images in the form of BGR, matplotlib, on the other hand, follows the order of RGB

OpenCV: Graph API: Converting image from one color space

There are different color conversation in OpenCv. Before converting an image, we need to consider about the image types. Some common image color types and number of channels are as follow. Image color type. No: of channels. BGR. 3. RGB. 3. BGRA. 4. RGBA. 4. GARY. 1. XYZ. 3. YCrCb. 3. HSV. 3. Lab. 3. Luv. 3. HLS. 3. YUV. 3. BGR image. BGR which. Welcome to another OpenCV tutorial. In this tutorial, we'll be covering thresholding for image and video analysis. The idea of thresholding is to further-simplify visual data for analysis. First, you may convert to gray-scale, but then you have to consider that grayscale still has at least 255 values. What thresholding can do, at the most basic. According to opencv docs these arguments are defined as : model - path to the .pb file with binary protobuf description of the network architecture config - path to the .pbtxt file that contains text graph definition in protobuf format. Resulting Net object is built by text graph using weights from a binary one that let us make it more flexible

In this tutorial, let's see how to identify a shape and position of an object using contours with OpenCV. Using contours with OpenCV, you can get a sequence of points of vertices of each white patch (White patches are considered as polygons). As example, you will get 3 points (vertices) for a triangle, and 4 points for quadrilaterals OpenCV is a powerful tool to process images. In this tutorial, we will introduce how to read an image to numpy ndarray. Python pillow library also can read an image to numpy ndarray. Python Pillow Read Image to NumPy Array: A Step Guide. Preliminary. We will prepare an image which contains alpha chanel. We will start to read it using python opencv