Brakes squealing

Here’s another question. I’ve noticed that whenever I start to apply the brakes, they squeal. They continue to do so until I press firmly on the pedal. I can’t localize to what rotor the sound is coming from.

Now that the car is up on stands, I figured it would be a good time to check this out as well. I figured I’d see some pads that were fairly worn, but to my eye, they appear to be OK. The rotors also show no wear and are smooth. Now, I may be mistaken in thinking that the wear on the pads is good. Would some pictures help here?

Any tips?