[FFmpeg-user] Extracting forced subtitles from a DVD.

[Michael Mueck]

Hi Nicolas,

In addition to the question below about the wrong subtitle track ending up in the output, I've also been looking into dvd2concat (which it looks like you wrote!). I was able to use it to make file.concat, but I'm having some trouble figuring out what to do with that file. I'd very much appreciate you pointing me in the right direction. Thanks!

Regards,

Mick


> On 2022.0428, at 16:19, Michael Mueck <mick.mueck at mac.com> wrote:
> 
> Thanks for responding Nicolas.
> 
>> On 2022.0428, at 14:01, Nicolas George <george at nsup.org> wrote:
>> 
>> Michael Mueck via ffmpeg-user (12022-04-28):
>>> I have decrypted and ripped all of my DVDs into individual VIDEO_TS
>>> structures for just the main movie or an individual TV episode. Each
>>> move or TV episode consists of a VIDEO_TS folder containing the
>>> original uncompressed
>>> 	VIDEO_TS.IFO,  VTS_01_0.IFO  and  VTS_01_[1->N].VOB  files.
>> 
>> This is already wrong. The VOB files do not map directly to the video
>> parts of the contents. If you do that, you will get also all the menu
>> crap in your resulting file.
> 
> The ripping software that I used dealt with that i.e. all the VOB files are categorically only for the main movie (or a given episode) and there are no menus at all. Notice that all my VOB files reference the same stream and the 1->N part is just the sequentially numbered sequence of 1GB files.
> 
>> Also, the subtitles palette is not in the VOB files.
> 
> Agreed, but for now I'm focusing on just getting the forced subtitles working right.
> 
>> You can generate a concat script to access the DVD hierarchy correctly
>> using the dvd2concat script in the tools directory.
>> 
>> It is entirely possible that doing so would fix your issue.
> 
> do I still need to do this given the above response? (I'll look into dvd2concat after sending this email).
> 
>> Also, do not re-encode the subtitles, use -c copy, it will be more
>> reliable.
> 
> I'm not sure how I latched onto the dvdsub codec, but I did just now try "copy" and I get the same good result when using an MKV as the input. However I get a curiously different result when using the VOB input with the "copy" subtitle codec - instead of an empty subtitle track I now get full-time English subtitles but the subtitle track is for stream 7 instead of stream 6! Stream 6 was the regular English subtitle track (that contained embedded forced subtitles) and Stream 7 is the English SDH subtitle track. That's weird!
> 
> Slightly off-topic: Is it really true that ffmpeg can't handle a standard DVD file structure (especially if everything is decrypted)?
> 
>> 
>> Regards,
>> 
>> -- 
>> Nicolas George
>