[FFmpeg-user] 6720x1200 proRes to wmv

Jim Shupert jshupert at pps-inc.com
Wed Apr 16 16:32:02 CEST 2014


> Some encoders need -mbd 2 with low quantisers / high
> bitrates, this is not resolution-dependent afaict.
> (Should be reproducible with very low resolutions
> and -qscale 2)
>
> This is primarily a limitation of the formats (not of
> FFmpeg) although you could argue that it should choose
> -mbd 2 in such cases (I don't think they can be easily
> detected).
>
> Carl Eugen
>
thanks brother,
yes I was able to make the warnings [ ...warning, clipping 1 dct 
coefficients ... ]
  go away with a   "  -qmin 3  "

I wonder what is the diff of

-qscale 2  & -qmin 2


This matter has  brought me to a greater understanding of such matters
thanks for the -mbd
( -mbd <int> E.V.. macroblock decision algorithm (high quality mode)
... though I will confess I am a bit fuzzy on what that -- means 
...exactly.. )

and on format / player support for Very large frm size...

It is an interesting matter -- total supported frame size in different 
players.
QT (win&mac) seems very forgiving - a high cieling
VLC , mplayer , win media player all tend to hollar  " 6720 x 1200 is to 
big " & fail .

one wonders how this will change with the coming of 4k etc.

thanks again




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