pomer stran u filmu v DivX

[Honza E]

On Wed, Apr 27, 2005 at 12:38:02PM +0200, Istvan Sobri wrote:
> Mám taky takový pocit, jen jsem chtil zjistit, jesti by to nešlo jinak.
> Ištván
> 
> On 4/27/05, David 'Ilicz' Klementa <ilicz na seznam.cz> wrote:
> > 
> > Hmm... rekl bych ze pomer stran se udava uz pri enkodovani do avi ne?

zdravim, dle doc mencoderu 

ftp://ftp1.mplayerhq.hu/MPlayer/DOCS/HTML-single/en/MPlayer.html#aspect
(je to nekde uz mozna i v cestine, staci vzit  ^/cs/ misto en) :

7.8. Preserving aspect ratio

DVDs and SVCDs (i.e. MPEG-1/2) files contain an aspect ratio value, which describes how the player should scale the video stream, so humans
won't have egg heads (ex.: 480x480 + 4:3 = 640x480). However when encoding to AVI (DivX) files, you have be aware that AVI headers don't
store this value. Rescaling the movie is disgusting and time consuming, there has to be a better way! 

There is

MPEG-4 has an unique feature: the video stream can contain its needed aspect ratio. Yes, just like MPEG-1/2 (DVD, SVCD) and H.263 files.
Regretfully, there are no video players outside which support this attribute of MPEG-4, except MPlayer. 

This feature can be used only with libavcodec's mpeg4 codec. Keep in mind: although MPlayer will correctly play the created file, other players
will use the wrong aspect ratio. 

You seriously should crop the black bands over and below the movie image. See the man page for the usage of the cropdetect and crop filters. 

Usage 

mencoder sample-svcd.mpg -ovc lavc -lavcopts vcodec=mpeg4:autoaspect -vf crop=714:548:0:14 -oac copy -o output.avi

a dle ne prilis optimisticke vety vyse plyne, ze neni jasne,
jak dalsi prehravace tento "parametr" podporuji.

Mozna, ze staci v .avi souboru pouze nahradit prislusny byte,
ale zustava na prehravaci (jinem nez mplayeru), zda ho (spravne) pouzije.

Pekny den!

Honza Eisner