Filtering Image

I have a resulting mask, and I want to filter out the vertical stripes, which are not “alarms”. The solid regions are alarms.

I have tried morphological operations with a rectangular kernel to filter out vertical stripes. But that has not yielded promising results.
Example with solid regions:

I want to know if there are any other methods that I can apply.

Post some images showing the results of what you have tried and explain why the results aren’t good for your purposes. Also post corresponding images with the results you are hoping to achieve.

Have you tried a median filter?

just curious, where do those images come from ?
what’s on the vertical axis ?

what about a more ‘whitelist’ approach –
find consecutive black strips on the x-axis
instead of ‘blacklisting’ single, vertical strips ?

show us the unfiltered source data.

it’s always the same thing. we can’t help you with a problem you created for yourself (that filtering).