now, i'm designing an ir receiver. i want to cut the burst pulse after comparator output, as the picture shows. VIN is the input here, the 24 burst pulse need be cut to 20 pulse, the following 12 burst pulse be cut to 10 pulse, i wonder how to realize this as simple as possible. i thought of timer and digital filter, but have no idea yet. someone tells me that, digital filter can realize the 'cut' function easily, but i don't find any related items (bpf, brf, lpf, hpf?). as i know, digital filter can include basic cells (adder, multiplier, delay cell), but i wonder what is the popular structure for these basic cells, and what is the scope of a normal digital filter?
thanks all.

Can't you just do this with a state machine?