tsMuxeR: How to keep subtitle parameters when remuxing?

[pYPsfVARqM3nH7hD]

Dear all,

I'd like to use tsMuxeR to remux some files which contain subtitles. I have understood that there basically are three types of subtitles (graphical (e.g. PGS), text-based and part-of-video), and have understood the difference between them. However, I've got some basic questions about how to keep subtitles in unaltered form when remuxing.

I have noticed that in tsMuxeR GUI in the "Subtitles" tab there are some options dealing with subtitle parameters (see attached screenshot). There might be more parameters available on the command line, but I didn't look into them yet, and it's probably not important for my questions. Whatsoever, I am not sure which type of subtitle these options apply to.

Regarding text-based subtitles. I understand that we can position them freely, that we have to choose a font for them, and so on, and can imagine the effect of those options. However, keeping subtitles in unaltered form also means keeping all related parameters' value when remuxing (e.g. font, font size, position, border, fading etc.). I am unsure how tsMuxeR behaves in this respect. If it encounters a file with text-based subtitles, does it automatically read those parameters and uses them when remuxing? Or would we have to read out the parameters, write them down and "manually" set set them when remuxing? If so, how can we read them out?

Regarding graphical subtitles, notably PGS subtitles: Do they need any extra parameters as well, or does the PGS format already contain all related parameters? In other words, do the subtitle options in tsMuxeR GUI make any sense with PGS subtitles at all? If so, how do we read the original PGS parameters from the source file?

Thank you very much in advance!


[Attachment 57703 - Click to enlarge]

[Ennio]

M2ts can hold several subtitles. A blu-ray compatable m2ts container only supports PGS (SUP) subtitles, which are image-based. As for text-based subtitles, tsMuxer only accepts srt.
Prior to muxing, srt's are converted into SUP, indeed according to the settings in the Subtitle tab, as your screenshot shows. These settings do not affect imported PGS streams, which are muxed unchanged. Where you do have the possibility to "Bind to video FPS" in case the SUP has a different framerate. And you can assign it to a so-called "3D-plane" in case of 3D blu-ray muxing.

As to retreiving all properties of both text-based and image-based subtitles, you would have to demux the subtitle streams and view them in several subtitle-tools at hand.
Which can also be used for editing and converting. Subtitle Edit, Aegisub, SUPread and BDSup2Sub are tools I often use, but there are many more.

[pYPsfVARqM3nH7hD]

@Ennio

Thanks a zillion times!

What you wrote is very valuable to me. Indeed, I'll be primarily interested in PGS subtitles in the next time, and it is good to know that I don't need to care about anything (perhaps except that "forced" thing). I won't change frame rates when muxing and will only mux streams which originally were intended to be used together. That is, the subtitle frame rate will always fit to the other streams.

P.S. Are you playing the Cello?

[Ennio]

P.S. Are you playing the Cello?

No, I don't, but I do love classical and orchestral music. As I do play bass, my avatar holds the bass key.
I added glasses to it as a wink to Ennio Morricone, one of my heroes. I had the honour of seeing him perform a couple of times. Sadly last year he past away.

[4L7zHhiyQO3Thui6]

@Ennio

Thanks for the explanation - nice idea. I also like EM and classical and baroque music, and I am using the same key, but Cello instead of bass Now I am afraid that we're getting off-topic ...

[Ennio]

No worries. It's your thread...