[MPlayer-users] encode2mpeg 0.3.1 possible bug but encoding OK

[Nico Sabbi]

Giacomo Comes wrote:

>>>Will your new muxer be able to mux ac3 audio?
>>>      
>>>
>>it's already possible and working
>>
>>    
>>
>>>And LPCM (lower priority compared to ac3)?
>>>
>>>Giacomo
>>>      
>>>
>>to say the truth it has no proriority at the moment :)
>>    
>>
>
>Nico,
>I have other requests/suggestions for your new
>muxer. Please see what you can do :-).
>
>1) add the possibility to set the "pulldown" flag
>like the -p option of mpeg2enc
>  
>

NTSC content is giving me a lot of problems. Can you please explain in
depth or provide a  link  how on pulldown works ?

>2) add the possibility to split the final mpeg
>stream at a specified value. Usually 700Mb or 800Mb.
>This is not required for DVD stream, but it is 
>necessary vor SVCD/VCD
>  
>

ok

>3) Currently is not possible to set for the mpegs
>the aspect ratio 1:1 if the video has resolution 720x480
>In this case an aspect of 4/3 is set
>(this is more a bug of the current code than a new feature
>for your new muxer)
>  
>

-mpegopts ...:vaspect=1/1:...

>4) This is a general questiom about mpeg streams.
>Consider this simple command line:
>mencoder  -of mpeg -ovc lavc -o TEST.mpg dvd://1 -ofps 30000/1001 -vf harddup -oac copy \
>  -lavcopts vcodec=mpeg2video:vbitrate=7500:aspect=16/9:vrc_buf_size=1835
>
>the mpeg will have an AVERAGE video bit rate of 7500
>When I play the resulting mpeg with MPlayer I see:
>	VIDEO:  MPEG2  720x480  (aspect 3)  29.970 fps    0.0 kbps ( 0.0 kbyte/s)
>this means variable bit rate (not 7500)
>
>if I add the libavcodec option vrc_maxrate=7500 then MPlayer shows:
>	VIDEO:  MPEG2  720x480  (aspect 3)  29.970 fps  7500.0 kbps (937.5 kbyte/s)
>
>But now the actual video bit rate is not 7500. That's the maximum.
>The average bit rate is lower.
>
>All the commercial DVD I have seen always shows a number in the bit rate field
>when played with MPlayer.
>This means that I need to add ALWAYS the option vrc_maxrate or there is another
>way to "set" in the stream the bitrate?
>
>Giacomo
>
>  
>

use -mpegopts :vbitrate=7500: to patch the nominal bitrate. Anyway the value
stored in the video bitstream indicates the max, not the average