[MPlayer-users] [Sorry for the base64 code]Re:Why -chapter works well but -ss fails for DVD?

[Alexander Roalter]

Bo Xie wrote:
>>This question was answered million times. Search the ML archive
> 
> 
> Calm down, please. My question is why -chapter works well and it is
> also a "seek" action for DVD. I know -ss fails for mplayer for a long
> time, but I want to know why? Then maybe we can fix it. Right? Thank
> you!
> 
> Best Regards,
> Xie Bo
> 
To my knowledge the IFO files contain the real sector numbers of the 
chapter beginnings, therefore the seeking works fairly well. -ss instead 
is of course only an estimation on the file size/video length, and so 
often enough wrong (merely all the time).

About the fixability? I don't know, would perhaps require scanning the 
entire video beforehand and creating a time/byte pos-map which would 
then be used. I don't know if something already exists on the DVD 
structures (or in the VOB stream, at least as hint), but to my knowledge 
DVD player (the commercial ones) do get the time right, and do not play 
the video at the beginning only to get the times... I'm a little bit 
confused about this...

Regards,
Alex