A way to get a source information from a stream

[drogus]

I'm writing an out of tree compiled module and I need to get information about a source of the stream (most importantly subtitles streams, but getting source for other media would be great as well). As an example, let's say a user loads 2 subtitles files from a local file, one for EN and one for PL language. What I would like to get is their paths, for example "C:\Movies\BladeRunner\BladeRunner.pl.srt" and "C:\Movies\BladeRunner\BladeRunner.en.srt". Is it possible? If yes, what's the best way to do that?