Rectangular image view in all window when zooming

Python
,
1

How can I visualize a rectangular image in the whole cv2 window when zooming.
I have a wide image, and I need to zoom in to use a mouse callback function, but it only uses the height of the image to zoom in.
There is a way to use the whole window height, and not just the image height?

2

welcome.

what is a “high”?

3

Hi.
I mean height, misspell sorry!!
I corrected it!!

4

ah, okay. could you maybe illustrate the issue with a screenshot?

5

This is how the image is loaded

image
image1920×1050 228 KB

6

This is when I zoom:

image
image1920×1050 214 KB

all the space above and below the image is not used when I zoom

7

ah!

yes, that seems to be a bug in the “fancy Qt” variant of highgui.

make sure you use the latest OpenCV, latest release v4.5.1 at least, better the master branch HEAD revision. see if the problem has been fixed already, or still persists.

8

So I developed a GUI, with opencv=4.2.0.
I just checked v4.5.1 still has the same issue

Thanks for the response

9

at this point I can only recommend opening an issue on github.

if you decide to submit an issue, provide minimal but complete reproducing source code. also include those screenshots. they make the issue easy to understand.

10

I just finish a simple project to solve this problem with mouse wheel to zoom images.

Here is effect:

image
image1761×735 115 KB

Check whole project