How to add black bars and re-encode a video keeping same original settings?

[maldon]

I want to create a 1920x1080 video, m2ts, but with a 132 pixel horizontal black bar to the top and bottom. Since I have to re-encode, my intention is to use exactly the same compression as the source, but how can I know all the original presets of the video?

Suppose I want to use Handbrake. How can I know, for instance...

-the original CRF that was selected?
-the original x264 Preset (slower, very slow, fast...)?
-the original x264 Tune (none, film, grain...)

But I can't re-encode with Handbrake because I want to export as m2ts. What software do you recommend me to use?

[FranceBB]

What software do you recommend me to use?

- Avisynth to add borders
- x264 via command line to encode
- FFMpeg or tsmuxer to mux in m2ts


-the original CRF that was selected?
-the original x264 Preset (slower, very slow, fast...)?
-the original x264 Tune (none, film, grain...)


Mediainfo if they used x264, but it's not guaranteed that whoever encoded in H.264 used x264

[SeeMoreDigital]

Does a two pixel anomaly really bother you that much?