[Ffmpeg-cvslog] Re: r5468 - trunk/libavformat/mov.c

[Michael Niedermayer]

Hi

On Tue, Jun 13, 2006 at 10:36:29AM +0200, Baptiste Coudurier wrote:
> Hi
> 
> Michael Niedermayer wrote:
> > [...]
> >>> it would also be nice if we could remux (-*codec copy) these
> >>> streams
> >> I totally agree and will do that. Im thinking about adding -newdata
> >> to ffmpeg commandline options, 

ok


> >> though I feel like stream mappings
> >> between formats will be a big mess. 

yes, probably


> >> Allowing only stream copy for
> >> now, and between same/compatible formats, maybe it's time for
> >> FORMAT_ID_MOV ?

hmm, iam not sure what exactly you are suggesting here ...


> >> 
> 
> You did not comment on that ? Is it stupid or ?
> 
> >>> [...]
> >> While we are at it, I also have 2 problems concerning
> >> demuxing/muxing mov/mp4:
> >> 
> >> - to properly seek into a non-interleaved mov/mp4 I need to know
> >> the exact timestamp in AV_TIME_BASE unit and not stream time unit,
> >> since I need to seek by time and not by chunk offset. I can still
> >> rescale to get the correct timestamps but It is not really
> >> accurate/correct.
> > 
> > i dont fully understand the problem, please elaborate
> 
> I can't refer to offsets when seeking into non-interleaved mov/mp4.
> 
> Atm the seek function search for the timestamp requested, find the
> corresponding chunk then seek all other streams according to the chunk
> offset found. It is false in the case of non-interleaved streams. I need
> also to seek all other streams according to the timestamp. Problem is
> that av_seek_frame pass timestamp in time base units of the stream on
> which the seek is requested.
> 
> I would need the original timestamp to rescale it to other streams time
> base unit. I can still revert the scaling and scale it again but like I
> said it is not accurate/correct.

no, you rescale from one timebase to another, no AV_TIME_BASE should be
involved, av_rescale_q() does exactly that ...

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

In the past you could go to a library and read, borrow or copy any book
Today you'd get arrested for mere telling someone where the library is