Preserve subtitles from TV recordings

[alexwilmac]

Hello,
I apologise if this subject has already been treated elsewhere in this forum (although it doesn't seem so based on the searches I did).
Nowadays, video editing is even more frequently based on PVR devices and TV recordings. And TV recordings, especially from foreign channel, are provided with subtitles that come very useful.
I have a SAT decoder with PVR functions. It records in format called TRP which is perfectly read by VLC also regarding the subtitles (whom you can switch on or off) but I cannot edit them by iMovie for MacOs, for example.
I use mainly a Mac although I've also a Windows PC but I'd rather use the
Mac because at the moment the PC is not in my availability.

Avidemux is also able to read these TRP video files but, after editing, it looses the subtitles.
I hoped that Avidemux, who's got a lot of features and controls and also a section about Subtitles, would manage them either to force them or to switch them on and off by VLC or similar players.
But I haven't found a way although I've tried probably almost every combinations possible.
Is it possible by Avidemux?
And, incidentally, if someone knows another way and another software to get to this goal I'll thank them for letting me know! I tried also conversion softwares to be able to convert in formats importable in iMvie but none of these softwares are able to preserve the subtitles.

Thanks for your help.

[mean]

It's not easy to do, so dont expect it for the near future

[yami]

There is a captions extractor for Windows (only ) here: http://kitsunekko.net/subtitles/japanese/Caption2Ass_PCR_With_Gaiji_List_Updated.rar
I never tried it, I only have Windows as VM and I don't like going there ^^
You can extract the uncut ccs there, but you have to adjust it later (with Aegisub) then you can mux Video and ccs (as srt or ass) down to mkv with Mkvtoolnix. I don't know, if iMovie can interpret mkv (I honestly don't use it). If it only likes mp4 and such, you will have to put the subs in as hardsub (with Handbreak as Avidemux doesn't have filters in again that could do it). But you can't switch off the subtitles then.