[MEncoder-users] Re: help with simple task: crop, scale, encode

[Molle Bestefich]

Dominik, I'm very grateful, thank you very much!

Dominik 'Rathann' Mierzejewski wrote:
> > # mencoder input.vob \
> > -vf crop=700:428:8:74 \
> > -vf scale=350:-2 \
>
> man mplayer

Didn't read the whole manual.
I use a lot of applications, I look at a lot of man pages and other
docs, and there's no way that I have the time to read all of them...

mencoder would be much more user friendly if it warned about these
things - it's very easy to spot an error like this (there's two "vf"
options) and print a warning..

Then again, the developers probably has more important things to fix,
I guess they weigh the time they use to answer questions like this
against how much effort printing a warning would be...  Hmm.

> Another -vf option overwrites the previous one.

Thanks :-D

I now separate filters with comma instead.

Seems like mencoder applies them in the opposite order that I ask it to, though:

===================
Opening video filter: [scale w=350 h=-2]
Opening video filter: [crop w=700 h=428 x=8 y=74]
Crop: 700 x 428, 8 ; 74
===================

Aye?

> -noautoexpand

Thanks!

> > Opening video decoder: [mpegpes] MPEG 1/2 Video passthrough
> > VDec: vo config request - 720 x 576 (preferred colorspace: Mpeg PES)
> > The selected video_out device is incompatible with this codec.
> > Try adding the scale filter, e.g. -vf spp,scale instead of -vf spp.
> > VDecoder init failed :(
> >
> > # Doesn't look too god.
> > # Not sure what it means by "vo config request",
> > # I haven't requested any vo config.
> > #
> > # I haven't selected a video_out device either, as
> > # mencoder did not accept my "-vo null" option.
> > # So how do I tell it to not try to output anything?
> > #
> > # It tells me to try adding the scale filter, but the scale
> > # filter is already added since I want to downscale the video.
>
> Irrelevant, but if you don't like it, add "-vc -mpegpes,"

Okey dokey, "-vc mpeg12" did the trick.  Thanks!

> > # The ODML: warnings doesn't look too good either, what do they mean?
>
> That you haven't specified video aspect.

Isn't video aspect just x:y ?
mencoder knows what size the video is, doesn't it?

The resulting video should be 350x214, so should I use
"-force-avi-aspect 1.63" ?

Or is it better not to?

> > # Why does it skip frames?
>
> To maintain A-V sync.

Thanks!