Why is AVI video so large?

A general forum for all messages that don't quite fit into the other forums.

Moderators: Admin, Moderator Team

Post Reply
brain.nz
Member
Member
Posts: 33
Joined: Sun Jul 30, 2006 6:18 am

Why is AVI video so large?

Post by brain.nz »

Hey everyone, I was just wondering why is AVI video so large in file size compared to Quicktime and MPEG?

Cheers,
brain.nz
[img]http://i80.photobucket.com/albums/j184/brain_nz/brain-nz.gif[/img]
slimdog55
Posting Freak
Posting Freak
Posts: 456
Joined: Fri Feb 14, 2003 1:28 am
Location: Huntley, IL, USA

Post by slimdog55 »

Usually AVI is uncompressed and much higher quality than the compressed MPEG and Quicktime formats.
brain.nz
Member
Member
Posts: 33
Joined: Sun Jul 30, 2006 6:18 am

Post by brain.nz »

why does the file of the video increase if you convert from MPEG to AVI? How does the video become higher quality from MPEG?
[img]http://i80.photobucket.com/albums/j184/brain_nz/brain-nz.gif[/img]
User avatar
DEDFX
Forum Veteran
Forum Veteran
Posts: 1228
Joined: Sun Apr 10, 2005 5:59 pm
Location: eastern MA
Contact:

Post by DEDFX »

You mean the size of the file? Because it's becoming an AVI now. The program recognizes it as a video file, not MPG so you can compress that to smaller size or leave it the way it is (AVI) even though its MPEG.
Ornsack
Moderator
Moderator
Posts: 1520
Joined: Sat Jun 01, 2002 11:43 pm
Location: Bristol, England
Contact:

Post by Ornsack »

AVI can be whatever size you want it to be. Most AVI codecs use high compression for editing and what not.

MPEG was designed to be smaller in size. I wouldn't use it for editing.

Quicktime is much like AVI, you can use any codec or compress to any file size. There's probably a myth that it's smaller in size because they released compressed trailers all the time in Quicktime.

An AVI DV file is the same size as a Quicktime DV file, for example.
[url=http://www.youtube.com/watch?v=loFABl-1Zcw]THE SALESMAN - YouTube[/url]
Jperson
Forum Addict
Forum Addict
Posts: 699
Joined: Tue Jul 11, 2006 8:54 am
Location: London, UK
Contact:

Post by Jperson »

Stupid question: What does AVI and DV stand for? I know what they are but don't know what they stand for, I think DV is digital video (am I right?) and the V in AVI is possibly also video, can anyone fill me in here?
[url=http://tinite.com][img]http://onstoryline.com/Atinitefilmsstrip.gif[/img][/url]
User avatar
Jimbobsquarepants
Posting Freak
Posting Freak
Posts: 242
Joined: Thu Feb 16, 2006 3:25 pm
Location: Kent, England, Europe, Earth
Contact:

Post by Jimbobsquarepants »

avi is audio video..............integrated....or something not sure on the I but it is audio video something
www.freewebs.com/martinman300
no-budget film making.
film fanatic
Posting Freak
Posting Freak
Posts: 476
Joined: Fri Jul 18, 2003 5:42 pm
Location: New Brighton, Liverpool, England
Contact:

Post by film fanatic »

Audio / Video Interleaved, and MPEG is Moving Pictures Expert Group.
UFProductions
Forum Veteran
Forum Veteran
Posts: 1479
Joined: Sun Apr 18, 2004 5:12 am
Location: Calgary, Alberta, Canada

Post by UFProductions »

I thought it was Audio / Video Interlaced, but shmeh... I guess I was wrong.
Last edited by UFProductions on Wed Aug 09, 2006 1:35 am, edited 1 time in total.
Losing consciousness,
in the arms of an angel,
I find only peace.
Ornsack
Moderator
Moderator
Posts: 1520
Joined: Sat Jun 01, 2002 11:43 pm
Location: Bristol, England
Contact:

Post by Ornsack »

Nah, only recently with the advent of DV (Digital Video, by the way!) that footage has been able to be interlaced properly.
[url=http://www.youtube.com/watch?v=loFABl-1Zcw]THE SALESMAN - YouTube[/url]
brain.nz
Member
Member
Posts: 33
Joined: Sun Jul 30, 2006 6:18 am

Post by brain.nz »

AVI stands for Audio Video Interleaved.
[img]http://i80.photobucket.com/albums/j184/brain_nz/brain-nz.gif[/img]
rhys
Forum Addict
Forum Addict
Posts: 983
Joined: Mon Jun 13, 2005 8:01 am
Location: Victoria, Australia

Post by rhys »

Coool. Does anyone know what jpeg stands for?
Hide or fight for your life?
Adam
Moderator
Moderator
Posts: 367
Joined: Sun May 26, 2002 7:20 pm

Post by Adam »

Similar to MPEG

JPEG = Joint Photographic Experts Group

http://en.wikipedia.org/wiki/Jpeg
Matt
Webmaster
Webmaster
Posts: 627
Joined: Tue May 14, 2002 10:28 am
Location: Bristol, England
Contact:

Post by Matt »

Remember that AVI is a container format. The codec defines how the frames are compressed. When you deal with an AVI you need to know what the codec is. AVI on it's own is not enough info. AVI is like a filing cabinet containing pieces of paper that represent frames. The codec is equivelent to what language is written on the paper. It could be French, German or numbers etc.

Therefore AVI isn't 'big' or 'small' because it all depends on the codec.

The size of a file does not determine the quality. When you convert a 50Mb MP3 to CD is takes up ten times as much space because that is what the format demands ... but the quality can *never* go up. Just because something is on DVD doesn't mean it is better quailty than a clip filmed on a mobile phone. There is a difference between what *potential* a format has for delivering quality and what it *actually* delivers for a given clip.
Raptor
Forum Veteran
Forum Veteran
Posts: 1027
Joined: Sat Sep 06, 2003 5:47 am
Location: Altoona, PA, USA

Post by Raptor »

Right on on the 'container concept Matt, the big difference between AVI and MPEg is how the frames are encoded, the frames in an AVI are compressed based on the selected codec, but each frame contains all the information needed to display that frame. In Mpeg, a GOP is used ( group of pictures) commonly 15 frames. the first frame in the GOP contains the full frame info, the successive frames in the gop contain only the information in each frame that has changed from teh first frame. One of the reasons why MPEG is not a preferred editing format. It still works well, since broadcast satelites use MPEG encoding and that is edited all the time. MPEG files get bigger when converted to AVI since all the frame info is reinserted in each frame during the conversion.
The UNDERGROUND
[url]http://theundergroundtv.com[/url]
Music television for unsigned bands
Post Reply