Get the red lines only. Discard anything else

Hello

I need a thresholding to get the red pixels (lines) only and discard anything else. Like a masking of the red lines (see attached) and omit everything else.

Any help please?

[Rik]

Do you need to reproduce the red lines, or do you have them already and need to locate them?

[Stelios Fanourakis]

No worries Rik. I found what I was looking for. Thanks anyway