rendering down my video to save space?

[Bansaw]

I have a whole load of AVI files on my hard drive and want to free up some space.

What would you reccommend I render them down to, MPG2 720x480 ... what bit rate and other settings would you reccommend to preserve quality?

Thanks!

[mats.hogberg]

mpg is less efficient than most common AVI video codecs, so, unless we're talking about uncompressed or DV or other low compression AVI, reencoding to mpg will likely make your video 3-4 times bigger if you want to lose as little quality as possible.
740x480 mpg (DVD specs) would be in the 6000 kbps range, give or take 30%. What bitrate is used in your original AVIs? Use GSpot to tell.

/Mats

[Bansaw]

Thanks!

My final format is going to be MPG2 anyway as I am making DVDs, so I am thinking "why shouldn't I render my AVIs down now instead of having then clog up my HDD?"

I might check out low-compression AVI though. I wonder if low-c does save so much space?[/b]

[guns1inger]

What type of avi are they now ?

If they are DV and you intend to go to DVD, then edit them if necessary, then encode to mpeg-2 at the bitrate you would use for DVD. Going to anything else, unless lossless, will only cost you dearly in quality.

[Bansaw]

My AVIs are totally uncompressed...

Are you recommending 6.5Mbps (90 mins of video on a DVD, with a 224Kbps audio),
or lower at 4.7Mbps (about 2 hours apparently on a DVD, with a 128Kbps audio).

I don't know how Vegas would render a 4.7Mbps quality though?

[guns1inger]

What do you mean, uncompressed ? Uncompressed video is huge - 100+ GB. You have a 40 GB drive.

What is the source ? If you are unsure, use G-Spot to tell you.

[mats.hogberg]

2 hours is max (imo) for a single layer DVD. 1.5 hours is better. But it all depends on what's in the video - talking heads shot with a still camera get by with very little bitrate - the average holiday handheld video needs as much as it can get. Like I've said before, and guns1inger say, a GSpot screen shot of one of the files is necessary to give you further advice. Only one more: If you know your desired end format - go there in as few steps as possible. If you have to reencode, reencode once.

/Mats