OpenCV Bug Report: Assertion Error in 'cv::resize'

Introduction

OpenCV is an open-source computer vision library that is widely used in various image processing and computer vision applications. However, sometimes it can throw errors that can be difficult to understand. One such error is the assertion error that occurs in the 'cv::resize' function.

Error Details

When resizing an image using the 'cv::resize' function, an assertion error may occur with the following message:

OpenCV(4.5.4-dev) D:\a\opencv-python\opencv-python\opencv\modules\imgproc\src\resize.cpp:4051:
error: (-215:Assertion failed) !ssize.empty() in function 'cv::resize'

This error message indicates that the input image size is empty. The assertion error occurs because the 'cv::resize' function requires a non-empty input image to perform the resizing.

Possible Causes

There may be several reasons why this assertion error occurs. One possible cause is that the image size is not properly initialized or defined. Another reason could be that the image file path may be incorrect or the image file may be corrupted. Additionally, there may be errors in the code logic that cause the assertion error.

Troubleshooting Steps

Here are some possible troubleshooting steps that can help resolve the assertion error in 'cv::resize':

1. Check that the input image size is not empty. Ensure that the input image is properly initialized and has a valid size.

2. Verify that the image file path is correct and the image file is not corrupted. Try opening the image file using a different image viewer or program.

3. Check the code logic for any errors. Ensure that the code is properly written and that all functions are used correctly.

4. Make sure that the OpenCV library is properly installed and linked with the application.

5. Update to the latest version of OpenCV to ensure that any known bugs or issues have been addressed.

Conclusion

The assertion error in 'cv::resize' occurs when the input image size is empty. It can be caused by several factors, including incorrectly initialized images, incorrect file paths, and errors in the code logic. Following the above troubleshooting steps can help resolve the issue and ensure that the 'cv::resize' function works as expected.