Back ArrowExplore all topics
technology logo
technology logo

Image rotation using OpenCV

share link

by vigneshchennai74 dot icon Updated: Feb 17, 2023

Solution Kit Solution Kit  

Attempting to create a new image from an input image by swapping the positions of the rows and columns using nested loops, and then writing the resulting image to a file using the OpenCV library


OpenCV (Open Source Computer Vision) and NumPy are two powerful libraries in Python that are widely used in computer vision, image processing, and machine learning applications. Here's a brief overview of how each library can be used. OpenCV provides a variety of computer vision algorithms and functions for image and video processing.


  • These functions range from basic image filtering, resizing, and rotation to advanced feature detection, object recognition, and video analysis.
  • OpenCV can read and write a variety of image and video formats, making it easy to work with different types of media.
  • OpenCV has interfaces for several programming languages, including


h, w, c where h, w, and c represent the height, width, and number of color channels in the new array. A nested loop is a loop inside another loop. It is a common programming construct used to iterate over multiple levels of data, such as two-dimensional arrays or matrices. cv2.imwrite is a function provided by the OpenCV library that is used to write an image to a file on a disk. The function takes two arguments: the filename of the image to be saved, and the image data to be written.


Here is the example how to rotate the image:

Preview of the output that you will get on running this code from your IDE


CODE

In this solution we use the Imread function of the OpenCV.

Python - Rotate Image

PythondotLines of Code : 35dotLicense : Strong Copyleft (CC BY-SA 4.0)

Dependent Libraries : 
img = cv2.imread('texas_longhorns_log.png')

h,w,c = img.shape

empty_img = np.zeros([h,w,c], dtype=np.uint8)

for i in range(h):
    for j in range(w):
        empty_img[i,j] = img[j-1,i-1]
        empty_img = empty_img[0:h,0:w]

cv2.imwrite("tester1.png", empty_img)

h,w,c = img.shape

empty_img = np.zeros([h,w,c], dtype=np.uint8)

for i in range(h):
    for j in range(w):
        empty_img[i,j] = img[h-j-1,w-i-1]
        empty_img = empty_img[0:h,0:w]

cv2.imwrite("tester2.png", empty_img)

h,w,c = img.shape

empty_img = np.zeros([h,w,c], dtype=np.uint8)

for i in range(h):
    for j in range(w):
        empty_img[i,j] = img[h-i-1,w-j-1]
        empty_img = empty_img[0:h,0:w]

cv2.imwrite("tester3.png", empty_img)
  1. Copy the code using the "Copy" button above, and paste it in a Python file in your IDE.
  2. Import open Cv and Numpy library
  3. Modify the name, location of the image to be rotate in the code.
  4. Run the file to rotate the image.


I hope you found this useful. I have added the link to dependent libraries, version information in the following sections.


i found this code snippet by searching for "Image rotation using OpenCV" in kandi. You can try any such use case!

Dependent Libraries

opencvby opencv

C++ doticonstar image 69057 doticonVersion:4.7.0doticon
License: Permissive (Apache-2.0)

Open Source Computer Vision Library

Support
    Quality
      Security
        License
          Reuse

            opencvby opencv

            C++ doticon star image 69057 doticonVersion:4.7.0doticon License: Permissive (Apache-2.0)

            Open Source Computer Vision Library
            Support
              Quality
                Security
                  License
                    Reuse

                      numpyby numpy

                      Python doticonstar image 23587 doticonVersion:v1.24.3doticon
                      License: Permissive (BSD-3-Clause)

                      The fundamental package for scientific computing with Python.

                      Support
                        Quality
                          Security
                            License
                              Reuse

                                numpyby numpy

                                Python doticon star image 23587 doticonVersion:v1.24.3doticon License: Permissive (BSD-3-Clause)

                                The fundamental package for scientific computing with Python.
                                Support
                                  Quality
                                    Security
                                      License
                                        Reuse

                                          If you do not have OpenCV that is required to run this code, you can install it by clicking on the above link and copying the pip Install command from the OpenCV page in kandi.

                                          You can search for any dependent library on kandi like OpenCV, numpy

                                          Envorinment Tested

                                          I tested this solution in the following versions. Be mindful of changes when working with other versions


                                          1. The solution is created and executed in python version 3.7.15 .
                                          2. The solution is tested on OpenCV 4.6.0


                                          Using this solution, we are able to rotate an image using the OpenCv library in Python with simple steps. This process also facilities an easy to use, hassle free method to create a hands-on working version of code which would help us rotate an image in Python

                                          Support

                                          1. For any support on kandi solution kits, please use the chat
                                          2. For further learning resources, visit the Open Weaver Community learning page.

                                          See similar Kits and Libraries

                                          Open Weaver – Develop Applications Faster with Open Source

                                          kandi

                                          Community and Support

                                          Company

                                          Follow

                                          • © 2023 Open Weaver Inc.