[gentoo-user] large .avi video files, re-encode ?

[gentoo-user] large .avi video files, re-encode ?

[Dave S]

Hi all,

I have a bunch of .avi video files that I use in a openoffice presentation, 
they are nice and clear but really large files (1 - 2 GB each !).

I know nothing of video files, is it possible for me to re-encode them to a 
more efficient format without loosing quality ?

Any suggestions ?

Dave
-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] large .avi video files, re-encode ?

[Arturo 'Buanzo' Busleiman]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Dave S wrote:
> Hi all,
> 
> I have a bunch of .avi video files that I use in a openoffice presentation, 
> they are nice and clear but really large files (1 - 2 GB each !).
> 
> I know nothing of video files, is it possible for me to re-encode them to a 
> more efficient format without loosing quality ?

I use something like this. Adapt for your usage. It takes some parameters, but it's mainly used for
dvd ripping:

#!/bin/sh
rm frameno.avi
echo "DVD TITLE: $1"
echo "OUTPUTFILE: $2"
echo "SID: $3"
echo "AID: $4"
echo "Is that what you want? Press enter for OK, CTRL+C to cancel."
read k
mencoder dvd://$1 -sid $3 -aid $4 -ovc frameno -o frameno.avi -oac mp3lame -lameopts
mode=1:vbr=2:q=6 -af volnorm -af-adv force=0
mencoder -oac copy -ovc xvid -xvidencopts bitrate=-1400000:me_quality=6:chroma_opt:vhq=0:pass=1
dvd://$1 -sid $3 -aid $4 -o /dev/null
mencoder -oac copy -ovc xvid -xvidencopts bitrate=-1400000:me_quality=6:chroma_opt:vhq=0:pass=2
dvd://$1 -sid $3 -aid $4 -o $2

Check out the bitrate= parameter in the last two commands. The negative number tells mencoder to
create a 1.4gb file (that's 1400000kilobytes, rounded up, not exact 1.4gb).

- --
Arturo "Buanzo" Busleiman - Consultor Independiente en Seguridad Informatica
¿No sabés a dónde ir a comer o tomar algo? Visitá www.vivamoslavida.com.ar
LISTA DE CASAMIENTO: Cualquier Fravega a nombre de Busleiman (37520).
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.5 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFFlAFoAlpOsGhXcE0RAvgPAJ4t4fDkcj1GPiWOEiKDfqdFu46wFQCfX8XT
FrXJgaKdE35E5dcOOgN1XJY=
=x/vp
-----END PGP SIGNATURE-----
-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] large .avi video files, re-encode ?

[Dave S]

On Thursday 28 December 2006 17:39, Arturo 'Buanzo' Busleiman wrote:
> Dave S wrote:
> > Hi all,
> >
> > I have a bunch of .avi video files that I use in a openoffice
> > presentation, they are nice and clear but really large files (1 - 2 GB
> > each !).
> >
> > I know nothing of video files, is it possible for me to re-encode them to
> > a more efficient format without loosing quality ?
>
> I use something like this. Adapt for your usage. It takes some parameters,
> but it's mainly used for dvd ripping:
>
> #!/bin/sh
> rm frameno.avi
> echo "DVD TITLE: $1"
> echo "OUTPUTFILE: $2"
> echo "SID: $3"
> echo "AID: $4"
> echo "Is that what you want? Press enter for OK, CTRL+C to cancel."
> read k
> mencoder dvd://$1 -sid $3 -aid $4 -ovc frameno -o frameno.avi -oac mp3lame
> -lameopts mode=1:vbr=2:q=6 -af volnorm -af-adv force=0
> mencoder -oac copy -ovc xvid -xvidencopts
> bitrate=-1400000:me_quality=6:chroma_opt:vhq=0:pass=1 dvd://$1 -sid $3 -aid
> $4 -o /dev/null
> mencoder -oac copy -ovc xvid -xvidencopts
> bitrate=-1400000:me_quality=6:chroma_opt:vhq=0:pass=2 dvd://$1 -sid $3 -aid
> $4 -o $2
>
> Check out the bitrate= parameter in the last two commands. The negative
> number tells mencoder to create a 1.4gb file (that's 1400000kilobytes,
> rounded up, not exact 1.4gb).
>
> --
> Arturo "Buanzo" Busleiman - Consultor Independiente en Seguridad
> Informatica ¿No sabés a dónde ir a comer o tomar algo? Visitá
> www.vivamoslavida.com.ar LISTA DE CASAMIENTO: Cualquier Fravega a nombre de
> Busleiman (37520).


Thanks for that I will give it a go :)

Dave

-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] large .avi video files, re-encode ?

[Dave S]

On Thursday 28 December 2006 17:39, Arturo 'Buanzo' Busleiman wrote:
> Dave S wrote:
> > Hi all,
> >
> > I have a bunch of .avi video files that I use in a openoffice
> > presentation, they are nice and clear but really large files (1 - 2 GB
> > each !).
> >
> > I know nothing of video files, is it possible for me to re-encode them to
> > a more efficient format without loosing quality ?
>
> I use something like this. Adapt for your usage. It takes some parameters,
> but it's mainly used for dvd ripping:
>
> #!/bin/sh
> rm frameno.avi
> echo "DVD TITLE: $1"
> echo "OUTPUTFILE: $2"
> echo "SID: $3"
> echo "AID: $4"
> echo "Is that what you want? Press enter for OK, CTRL+C to cancel."
> read k
> mencoder dvd://$1 -sid $3 -aid $4 -ovc frameno -o frameno.avi -oac mp3lame
> -lameopts mode=1:vbr=2:q=6 -af volnorm -af-adv force=0
> mencoder -oac copy -ovc xvid -xvidencopts
> bitrate=-1400000:me_quality=6:chroma_opt:vhq=0:pass=1 dvd://$1 -sid $3 -aid
> $4 -o /dev/null
> mencoder -oac copy -ovc xvid -xvidencopts
> bitrate=-1400000:me_quality=6:chroma_opt:vhq=0:pass=2 dvd://$1 -sid $3 -aid
> $4 -o $2
>
> Check out the bitrate= parameter in the last two commands. The negative
> number tells mencoder to create a 1.4gb file (that's 1400000kilobytes,
> rounded up, not exact 1.4gb).
>
> --
> Arturo "Buanzo" Busleiman - Consultor Independiente en Seguridad
> Informatica ¿No sabés a dónde ir a comer o tomar algo? Visitá
> www.vivamoslavida.com.ar LISTA DE CASAMIENTO: Cualquier Fravega a nombre de
> Busleiman (37520).


1GB file compressed to 5M (OK so there was not too much changing on the 
screen, mainly cursor & some popups) - I call that a success :)

Cheers

Dave

-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] large .avi video files, re-encode ?

[Strong Cypher]

[-- Attachment #1: Type: text/plain, Size: 302 bytes --]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

could you give us the original format of your video ?
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (MingW32) - WinPT 1.2.0

iD4DBQFFlAGUEg3iyspSWPARAtxsAJiB/lfH/ObIGkgjJH8I1PwXQ9W4AJ9iViw4
+Bd8C3vHS27yHX7/yyFdZw==
=Jqp4
-----END PGP SIGNATURE-----

[-- Attachment #2: Type: text/html, Size: 341 bytes --]

Re: [gentoo-user] large .avi video files, re-encode ?

[Dave S]

On Thursday 28 December 2006 17:40, Strong Cypher wrote:
> could you give us the original format of your video ?

The .avi files were directly generated by a screen capture program

Dave
-- 
gentoo-user@gentoo.org mailing list

Re: [gentoo-user] large .avi video files, re-encode ?

[Dan]

On Thu, 28 Dec 2006 18:27:16 +0000
Dave S <gentoo@pusspaws.net> wrote:

> On Thursday 28 December 2006 17:40, Strong Cypher wrote:
> > could you give us the original format of your video ?
> 
> The .avi files were directly generated by a screen capture program
> 
> Dave
the avi format is a container format that can work with multiple codecs
(see below).   perhaps you just need to re-encode them so that either
they use a better codec or they are lower qualilty in the same codec
(quality is directly proportional to size). Or use a better file format
alltogether if you wish.  

to do video stream editing i recommend the transcode package, as that's
the only one I know if.  

some quick info on avi's

http://en.wikipedia.org/wiki/Audio_Video_Interleave says:

(quotes)

Audio Video Interleave, known by its acronym AVI, is a multimedia
container format introduced by Microsoft in November 1992 as part of
the Video for Windows technology. AVI files contain both audio and
video data in a standard container that allows simultaneous playback.
Like DVDs, AVI files support multiple audio and video streams, although
these features are rarely used. Most AVI files also use the file format
extensions developed by the Matrox OpenDML group in February 1996.
These files are supported by Microsoft, and are known unofficially as
"AVI 2.0".
...
By way of the RIFF format, the audio/visual data contained in the
"movi" chunk can be encoded or decoded by a software module called a
codec. The codec translates between raw data and the data format inside
the chunk. An AVI file may therefore carry audio/visual data inside the
chunks in almost any compression scheme, including: Full Frames
(Uncompressed), Intel Real Time Video, Indeo, Cinepak, Motion JPEG,
Editable MPEG, VDOWave, ClearVideo / RealVideo, QPEG, MPEG-4 and others.
...
AVI is considered by many to be an outdated container format.There is
significant overhead when used with popular MPEG-4 codecs ...The
container has no native support for those codecs' modern features...
cumbersome hacks (in a programming context) are used,
causing incompatibilities in some players. Hacks are also used to
implement subtitles. The highly efficient H.264 codecs use even more
compression tricks, and thus are even more ill-suited to the format,
particularly Main and High Profile.
(end quotes)
-- 
gentoo-user@gentoo.org mailing list