Track back exported objects to pcap file

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I'm currently using Tshark commands into a python script to automatize net sniffing and file extraction. Now I have the problem that I need to track back the extracted object to the source pcap file. I tried to print the STDOUT but I just get information about packets while I would like to have the list of the exported filename (more or less what happens in Wireshark before saving the files to folder). I'm currently using a quick a dirty solution saving extracted object into folder named after the pcap file; but I'm wondering if I can read this information somehow in command output or to track back this connection in some other way.

Thank you in advance for the support.