From: Ole C. <Ole...@we...> - 2005-11-30 05:10:57
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Cyrus Patel wrote: > On 28 Nov 2005 at 16:51, Bob Forsman wrote: > > > Only rewriting timestamps does not involve cutting/remuxing, and does > not not influence synchronicity (unless you botch the rewrite) since > the PTS/DTS adjustment applies to all elementary streams equally. > > Simple example: > > Before rewrite: > pack: SCR 8 PTS 9 > pack: SCR 9 <pad/end of stream> > pack: SCR 0 <nav> > pack: SCR 1 PTS 2 > pack: SCR 2 PTS 3 > pack: SCR 3 PTS 4 > After rewrite: > pack: SCR 8 PTS 9 > pack: SCR 9 <pad> > pack: SCR 10 <nav> > pack: SCR 11 PTS 12 > pack: SCR 12 PTS 13 > pack: SCR 13 PTS 14 > > There are a couple of other things that need adjustment (or not - > subject to the presence of an ESCR), but in essence thats all there > is to rewriting timestamps. These "couple of things" include ensuring the player hardware's buffer do not overflow and underrun. So it is much more than what you outlined above. Afaik players flush their buffers on a Vob-ID change (cell change). So you start with empty buffers at SCR=0. If you simply rewrite SCR=0 to SCR=9 buffers will not flush and risk of overflow at some point later in the stream is more than probable. So it is more a job of re-muxing than SCR rewriting from my point of view. But if anyone feels need for it, please go ahead. But you are right in terms of synchronicity. PTS/DTS should not be affected. |