differnce between .DAT, .AVI, .MPEG in size

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i want to know what if i have a movie file of specific lenght. what would be the differnce in size if it was .MPEG,.AVI or .AVI

-- khalid gabel (the_real_kag@yahoo.com), April 23, 2003


It's impossible to answer this question. AVI file size depends on what codec you use, if any. MPEG size depends on the bit rate used when recording. DAT means VCD, which is 1150000 bits per second, so you can do the math. An AVI file could be the smallest of the three, if a DivX codec is used at a low enough bit rate. MPEG could even be the smallest if you use a very low bit rate.

-- Root (root@yahoo.moc), April 23, 2003.

no email address sorry. Anyway, i think what khalid meant is generally speaking if the capture resolution is the same for a clip that is the same length then avi would be larger than mpeg. and mpg2 is supposed to give you the same quality as mpg1 for a slightly lesser bit rate so in theory then next in line would be mpg1. Then mpg2. The order would be from larger to smallest avi, mpg1, mpg2. and of course like root said dat files would be in the middle because it is an mpg1. Daniel (my interpretation of the question)

-- Daniel (0000@00.com), April 24, 2003.

Ya, there is difference

AVI's r usually smaller than Mpg. But if you make a really really good quality of AVI, then it will be around MPG.


-- Monu (a@b.com), May 26, 2003.

Really? In my experience, MPEG has always been MUCH smaller than AVI. I have been working with Adobe Premiere for about six years doing professional video, and now DVD production. Maybe my AVI's are larger because I use a weird codec. AVIs compared to MPEGs have always been like .WAV files compared to .MP3. Technically, it is the same thing, without the video layers.

For example, I am putting a project on to DVD right now, TODAY even. My folder containing my AVI files to be converted to MPEG is 32GB. When they are all converted to MPEG, it will all fit on a 4.6GB DVD.

Any other questions?

-- Mr. Undisclosed (000@00.com), July 16, 2003.

.Avi is just a wrapper for the video, so as the answers have shown it can vary in file size depending on the codec and compression settings - I think a similar theory applies to .mpg files, that the rate of compression is adjustable. As far as the file size is concerned, my understanding is that .avi files encoded using Xvid or Divx (etc...) have a smaller file size than an mpg compression at the same quality settings. I think the difference is simlar to lossles and .mp3 audio encoding - a LAME encoded .mp3 or .ogg file is more like divx, in that it can use an advanced amount of compression, which reduces its resemblance to the source file minutely, whereas lossless formats like .ape and .mp+ are more like .mpeg, where it uses less advanced compressions, so a file of a similar quality to the .mp3 would take up more disk space, but also represent the source more acurately... or something like that.

I'm not sure of this tho...

-- Non (Non@hotmail.com), August 06, 2003.

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