[MPlayer-users] "Too many video packets in the buffer" playing a merged file

[Alessandro Di Rubbo]

> Date: Sat, 2 Oct 2004 20:10:01 +0300
> From: Ville Saari <113762 at vs.iki.fi>
> 
> On Sat, Oct 02, 2004 at 12:57:35AM +0100, Alessandro Di Rubbo wrote:
> 
> > In another guide, whose name I don't remember, I've read that it's better
> > encoding credits at a lower bit rate because all that black makes credits
> > bit rate bigger than full movie bitrate, and hence makes lower the quality
> > of movie parts that aren't credits.
> 
> Don't believe everything you read - all that black has exactly the opposite
> effect! Large areas of constant color need almost no bits.

I believe the first part of your phrase, so I don't believe the second one: I'll make some experiments... :-)
(anyway "all that black" wanted to mean "white credits moving on black background")

> The text in credits eats a horrible amount of bits, but a good encoder only
> needs to encode the new lines appearing form the bottom and everything
> else is just motion vectors. I just tested a bunch of movies by splitting
> the credits to separate file and checking the bitrate and every single one
> had less bitrate in the credits than in the rest of the movie! And I
> certainly hadn't done anything special to the credits while encoding them.

I have encoded the last two chapters of "2001: a Space Odissey" DVD and I've splitted the file in two parts:
- two-chapters.avi 226.1 kbits/s ~ 577 s
- movie.avi 631.9 kbits/s ~ 95 s
- credits.avi 145.9 kbits/s ~ 482 s 
You're right, but, in "2001:", credits are just white static words on black background...

> Date: Sat, 2 Oct 2004 12:29:46 -0700 (PDT)
> From: Loren Merritt <lorenm at u.washington.edu>
> 
> On Sat, 2 Oct 2004, D Richard Felker III wrote:
> > On Sat, Oct 02, 2004 at 08:10:01PM +0300, Ville Saari wrote:
> >>
> >> [...]
> > in general this is true. the only exception i can think of is when you
> > have really fancy backgrounds and stuff behind the credits eating lots
> > of bits, but the background still sucks enough that you don't want to
> > waste bits on it. :)
> 
> That case happens more often than I'd like. And it doesn't take a very 
> complex background to eat lots of bits from scrolling text. Especially if 
> it's interlaced text on a telecined background, like too many anime dvds.
> Even after deinterlacing, I've seen credits use 8x the bitrate of the 
> movie (at constant qp).

It sounds like what I read in that guide, mmm...

> BTW, I've seen large improvements from using qpel in credits, while qpel 
> hurts compression in the main movie. Concatenating (avimerge) the two 
> encodes works when decoded by libavcodec, but is it really legal mpeg4?

Can you tell me more about using qpel? And what does "legal" mean? Stricly ISO MPEG-4 compliant?


Alessandro


P.S. To rich. You wrote: "NEVER EVER use -nosound unless you actually intend for the final movie
to have no sound!!!", but if I want to create a Matroska (mkvmerging a SINGLE .avi and an external .ogg) can I use -nosound option? As I've said already, I've notice no problem doing that.
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