How to calculate size of a specific cavity in a protein for every frame in trajectory file? Here is the situation, I have trajecory file of a protein of interest. That protein has 2 main cavities that are participating in interraction with ligands or other proteins and also other cavities. Also residue numbers around this cavity are more or less known. I'm looking for a method or software to get volume of this cavities for every frame in trajectory. 

I want to specify a cavity around a residue and  get output for this cavity. What I am looking for is something like this:

Frame Cavity volume
1 1500 A^3
2 1499 A^3
3 1499 A^3
4 1499 A^3
5 1498 A^3


I tried CASTp, it was okey for singe frame if wrote it as pdb but not promising for a 100ns trajectory.

Also tried CAVER. CAVER was able to open a trajectory file and calculate cavity volumes for the frame that I chose but it was not possible to calculate cavity volumes for all of the frames and get output from it.

If anyone has any suggestion I'll be greatful.
In short, POVME exactly does this.