[NUT-devel] r20926 - trunk/DOCS/tech/nut.txt

[Michael Niedermayer]

Hi

On Wed, Nov 15, 2006 at 01:47:07PM -0000, Måns Rullgård wrote:
[...]
> >> I wasn't aware that NUT was intended exclusively for software decoders
> >> with huge buffers.
> >>
> >> > additionally having audio and video with arbitrary delay will not reduce
> >> > the problem but rather make it worse (i think you agree here?)
> >> >
> >> > and specifying exactly what delay there should be would again not really
> >> > change a thing or?
> >>
> >> The spec could allow for a constant offset between streams, possibly
> >> specified in a header field.  I can't think of a case where variable
> >> delay would make sense.
> >
> > and a constant delay (which doesnt match _your_ decoder) would help?
> > how? or should every nut file contain a arbitrary delay at the users
> > discretion, mpeg doesnt do that either it specifies the vbv rules
> > and decoders be it hw or sw are then designed to somehow demux and
> > decode the result, if they need extra buffering to deal with it
> > (every sw decoder i know of does) so be it
> 
> These cheap hardware decoders will of course not be able to handle *any*
> stream.  The difference between MPEG and NUT is that it is possible to
> create a valid MPEG stream with the necessary constraints.  The data sheet
> for a decoder tells you what the requirements are, and you can then make
> sure that the streams meet those requirements, or choose a decoder that
> can handle your streams.
> 
> MPEG is often used in closed systems, or in systems will very well defined
> constraints.  I see no reason why (a future, complete) NUT wouldn't be
> suitable as a base format in such systems.

well, is the dts ordering the only thing preventing use of nut in such
a system?
would addition of a delay field to each stream header which would then
be added to all timestamps in that stream solve the issue?
would a maximum 250ms on such a field be enough?
and some additional rule like delay MUST be 0 unless the file is encoded
for a specific specification requireing a larger delay?

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

In the past you could go to a library and read, borrow or copy any book
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