View Single Post
Old 16th October 2019, 09:58   #1715  |  Link
r0lZ
PgcEdit daemon
 
r0lZ's Avatar
 
Join Date: Jul 2003
Posts: 7,469
Quote:
Originally Posted by konikpolny View Post
Hi r0lZ,
why does BD3D2MK3D create a project with 2 different files eg.
00098.track_4608.Eng.2D.sup and
00098.track_4608.Eng.sup
for the same 2D subtitles? I always thought they are identical but I noticed their filesize is different.
The 2D stream must be converted to XML/PNG by BDSub2Sub before the conversion to 3D. Unfortunately, sometimes, BDSup2Sub creates bad PNG frames for some subtitles. (They are either completely transparent, or their size is 0x0 !). But I have noticed that converting the original subtitle stream from BD SUP to BD SUP has the effect of solving that issue. Therefore, to convert the stream to 3D, BD3D2MK3D begins by a (theoretically unnecessary) conversion to 2D and create the stream with the .2D.sup extension.

Also, sometimes a single subtitle is split in several identical parts in the original stream, and so close together that they appear as a single subtitle to the spectator (known as "multiple ODS"). BDSup2Sub has an option to concatenate these double subtitles together, to form a single subtitle. Therefore, unnecessary subtitles are removed during that first conversion to 2D.

For that reason, previously BD3D2MK3D muxed the converted stream in the final MKV, as it was theoretically free of unnecessary double subtitles and invisible black images. But I have noticed later that sometimes, BDSup2Sub misses some subtitles, and therefore the converted stream can be somewhat incomplete. Therefore, now, BD3D2MK3D muxes the original 2D stream (without the .2D extension) in the MKV, and uses the converted 2D stream for the conversion to 3D only.

It is also correct that the filesize changes when the stream is converted, even if you don't change the format. Of course, it's normal if BDSup2Sub has concatenated some double subtitles, but it seems that there is another bug here, as if you convert again the .2D.sub stream to SUB, you will notice again a filesize change. I'm not sure why, and it it's important, but now, I think that the less you convert is the better. Unfortunately, it is necessary to convert several times the original stream to convert it to 3D.
__________________
r0lZ
PgcEdit homepage (hosted by VideoHelp)
BD3D2MK3D A tool to convert 3D blu-rays to SBS, T&B or FS MKV
r0lZ is offline