Identify lines in spectrogram using python

Question

I have a long strip of data with some lines in it that are visually very clear (both blue and red), however, I can't seem to be able to identify them versus the background.

I've tried to average the array in in the time direction, run that through a low pass filter and then identify the peaks. But it does not seem to work. Therefore, I was wondering if perhaps the image itself can be used to look for the locations, using say openCV or such? enter image description here

• Christoph Rackwitz: lowpassing over time and finding extrema? that's a DSP problem, not a vision/image processing problem. your data isn't images, your data is a 1D signal. your plot is visualization, not data. the spectrograph is data but it's rarely considered an "image" because the axes are of different dimensions (time, frequency/wavelength) -- minimal reproducible example required, specifically the data underlying your illustration, i.e. the signal itself -- the color scale of your plot is misleading, and missing. the coloring suggests positive and negative amplitudes. I strongly doubt that. it probably just picked an average.
• Christoph Rackwitz: you say that you tried something and it didn't work. you should present the approach and the results, especially if the approach is plausible.