(Examples below use V1,V2,V3,V4 = -5,-3,+3,+5 respectively.)
If you know V1, V2, V3, and V4 you can use comparators and some logic:
Animated:
https://tinyurl.com/co35sre
The gate logic could be done in software e.g. on a microcontroller instead, if necessary. Make sure to choose comparators with appropriate output levels for the gates / microcontroller / whatever.
If you don't know V1, V2, V3, and V4 but you know the ratio between them and you know they'll remain roughly consistent you can use a similar circuit with capacitors to track the upper and lower input signal limits feeding voltage dividers for inputs to the comparators.
In both of the above circuits if the input slew rate is too low you will still get erroneous output during transitions (e.g transitioning from V2 to V4 will cross V3) so you may still have to do some output filtering (e.g. cap at output of
https://tinyurl.com/bsqla5c).
If you know the frequency of the inputs a buffer -> highpass filter -> comparator could do the job although might be a little trickier to set up:
Animation and circuit:
https://tinyurl.com/c8lkj8p
You might throw a small cap at the output to absorb noise.
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I specified a broken link for the second circuit. It is fixed now.
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Example using capacitors to track signal range; resistors determine threshold ratios within range:
https://tinyurl.com/c53x2ut (also has output filter -- cap at input is just to generate input with low slew rate and is not part of circuit).