Re: [MEncoder-users] MPEG muxer (was ERROR: SCR: warning; what does that mean?)

Nico Sabbi nsabbi at fastwebnet.it
Mon Jun 13 11:35:52 CEST 2005


>
>Hope you don't mind, that I'm still curious about the muxer :o) After 
>looking at the source, I got some more questions:
>
>Do you have any reason to use maxrate=174250 instead of 176400, which 
>for example transcode uses for VCD and I read somewhere on the net?
>
>Another thing I saw was, that the video buffer size in the muxer for 
>VCD is 46KB - like Mplex -, which is close to vrc_buf_size=376, but the

>mplayer manual recommends vrc_size_buf=327. This could mean loosing 
>some quality during encoding if the later is used and a bigger buffer 
>is assumed anyway. Or did I get something wrong?

since I don't have official [s]vcd specs, not even as drafts,
I used the same values as the most reliable muxer I know: dvb-mplex.
In any case the VBV values are not the same as the buffering values
in the PES and system headers

>
>>> By the way: I found that there is a non-documented (in terms of man 
>>> page) option skip_padding to create MPEGs with variable packet size.

>>> Is this one save to use?
>>>
>
>>  It will be removed soon because it's no more needed
>
>Why? There are other muxer which support this, for example
>
>	http://www.lilapple.com/mpspsm.html
>
>The question was more in the direction, if this feature works with 
>other players than mplayer.
>
>jps

because there shouldn't be empty spaces to fill with paddings 
with the new code.

There's no constant pack size requirement in plain mpeg (only in *vd), 
so streams produced without padding are still 100% compliant with the standard.







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