OpenCV – Reading An Image with python

Hi Guyz,

In this tutorial, I will discuss how to read an image in OpenCV using python.

OpenCV has the function called imread for reading an image. This imread function reads the image in BGR format. BGR stands for Blue Green Red.

This function takes two argument.

1. Image path
2. Flag

 There are three types of flags which this function takes.

1. IMREAD_COLOR 
2. IMREAD_GRAYSCALE
3. IMREAD_UNCHANGED

IMREAD_COLOR : This is the default flag which this function takes automatically. So if you want to read an image in the color format then you don’t have pass any flag. Or you can also pass 0. 

IMREAD_GRAYSCALE : When using this flag it read an image in grayscale format. Or you can also pass  1. 

IMREAD_UNCHANGED : Loads an image with transparency (Alpha channel). Or you can also pass -1.

import cv2 as cv

""" Reading Colored Image """

colored_image= cv.imread("nature.jpg") 

#Same statement can also be written as 

colored_image= cv.imread("nature.jpg",cv.IMREAD_COLOR) 

#Or it can also be written as

colored_image= cv.imread("nature.jpg",1)

""" Reading Image in grayscale format"""

gray_image= cv.imread("nature.jpg",cv.IMREAD_GRAYSCALE)

#Same statement can also be written as

gray_image= cv.imread("nature.jpg",0)

""" Reading Image With Alpha (Transparency)"""

alpha_image= cv.imread("nature.jpg",cv.IMREAD_UNCHANGED)

#Same statement can be written as

alpha_image= cv.imread("nature.jpg",-1)

Also checkout my other OpenCV tutorials

Thanks for reading 🙂 🙂