[MPlayer-users] Re: Re: Changing aspect-ration of an AVI file without reencoding it...

[ChristianHJW]

"Arpi" <arpi at thot.banki.hu> schrieb im Newsbeitrag
news:200209241309.g8OD9TGD025895 at mail.mplayerhq.hu...
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> the aspect ratio info is handled by the video codecs, and just like mpeg
> 1/2, mpeg4 (aka divx) supports it too. and with mencoder you can put it
into
> avi container too, preserving the aspect ratio info inside the mpeg4
header.
> the container does nothing with aspect, no matter if it's mpeg-ps (aka
.vob)
> or avi. yes, some containers, like .mov (and mcf?) has field for aspect
> ratio, it's nice for video codecs not supporting aspect itself.

You maybe dont care about that, but the AVI files you create that way will
be non-playable on almost every other OS with most other players, or need
manual adjustment of AR. This will be true for Windows especially, because
all MPEG4 decoders ( including Milan's ffdshow ) cant read this AR flag for
the time being. Also no MPEG 4 encoders for Windows, using AVI as container,
offers the possibility to edit the AR flag, for this very reason. It was
never planned for codecs to be contained in AVI, and shouldnt be done.

Pete Ross from XviD dev team told me recently that API 3 for XviD will have
such a AR flag, but currently XviD decoder doesnt make any use of that, nor
is it planned to support it.

I know Linux people dont care much about the rest of the world or
compatibility in general, but its wrong IMHO to motivate people to make
movies that are incompatible with all other platforms. Just my 2 cents, even
if i know you wont care too much.

 > PLEASE stop re-posting this message (or is it an autoresponder bot?)
every
> time someone mention 'AVI' and 'aspect' in the same mail... it's boring
and
> not even valid and wrong list for advertising a not even finished
fileformat
> A'rpi / Astral & ESP-team

This is not an autoresponder, nor is it a bot. I am simply trying to show
you the possibilities a new, open standard container could offer to the free
media world, hoping somebody reading here could be interested to join us to
COMPLETE the, i admit that, still more than unfinished MCF.

MCF would be at least in beta stage already when we had simply took the
'easy' VfW/AVI compatibility road like  .ogm is doing now. We decided to
take the hard way, trying to create a new open standard that is 100% future
proof, including a new 'common' codec handling API. It seems we finally get
some help now, as we will very likely drop transor API in favour of UCI (
http://uci.sourceforge.net ), saving us a hell lot of work.

I am sorry if my attempts to communicate the advantages of MCF here are
interpreted as 'advertising' . Of course i will stop posting about it now.
In the end, i am not working for money for a company, so i dont see why
communcating the idea behind an open standard project was such a bad thing
at all, but of course dont want to annoy the mplayer dev team with my
postings.

Regards

Christian