I have a few avis that are like 650 MB. My harddrive groans under the added weight. I don’t know of any programs though that can compress them and at least shave off 100 MB.
Does any body have any programs or techniques to recommend?
Unfortunately, I don’t have time to give a detailed response – plus, I only have a small amount of experience in this – but I’ll tel you what I know.
Basically, you can’t compress an AVI any further. However, you can re-encode the AVI with a lower bitrate. The problem with doing this is twofold.
First, you will lose picture quality when reducing the bitrate, so the final product will look worse than the original (possibly a blot** worse, if you don’t know what you’re doing).
Second, the re-encoding process can take a looooong time. Depending on the speed of your computer, you’re looking at anywhere from ~6 hours up to 24+ hours to re-encode the AVI.
Hopefully someone will come along and offer more detailed information, but it has been my experience that attempting to re-encode an AVI just to save a few hundred MB of space just isn’t worth it. Much easier to just invest in some CD-Rs and burn it to CD.
If reencoding the AVIs is really what you want, download VirtualDub and the XviD Video Codec [under “latest binary”]. Install XviD and VirtualDub, open your AVI in VirtualDub, set the Audio menu to “Direct Stream Copy” and the Video menu to Fast Recompress. Go to the Video, Compression…menu, choose XviD, and set it up how you like. Then go to File, Save as AVI…
XviD has a freakin’ BOATLOAD of settings you can play with, but it’s also decent at only showing them when you choose the advanced modes. You’ll probably just want to choose an unrestricted 1-pass encoding, then pick the bitrate you want. Bitrate / 8 * length of movie in seconds will get you an approximation of the size of your final movie in kilobytes. The lower you set the bitrate, the lower the quality. If you spend awhile poking around the various resources on the web, you can find out how to get much better quality for a given bitrate, but it gets really complex really fast.
Squeeze 'em till it Hertz!
I recompress AVIs as part of my job. Usually it takes a few minutes to compress a regular multi-gigabyte file down to a few megabytes.
But it depends on which software you use, what compressor you use, and a few other factors.
It has never taken more than a couple of hours for a particularly complex file. But 6 - 24 hours is absurd, and you may be thinking of how it used to be back in 1996 or something.
I have to admit that the only experience I have with encoding video was that one month or so a couple of years ago when I played around with ripping DVDs (that I owned) to my computer. Re-encoding an entire DVD down to fit on a CD – so that I could watch it on my non-DVD-enabled computer – took about 6-8 hours, IIRC. Of course, I could very well have flipped on some archaic setting that did very little besides slow down the encoding process without knowing it.
I threw out the 24+ hour thing as a warning because some people out there are still running some seriously out of date computers.
What codec/settings do you use? How exactly can you compress a multi-gig file into anything less than 200MB without having an absurd loss of quality? Unless you are talking about starting off with originally uncompressed files instead of originally DVD files. In which case, your comparing apples and oranges here.
GuanoLad
The compression that can take about 6 hours involves compressing DVD video from 4 Gb MPEG2 compressed files to 700 Mb DivX/XviD files that visually are only a bit worse than the originals. This usually involves at least two passes so that it is compressed as optimally as possible.
If those DVD files were uncompressed they’d be about 150 Gb.
BTW, the reason why they’re often about 650 or 700 Mb is so that they can fit onto CD’s. I recommend you copy them onto cheap CD’s (and not zipped either) if they’re not zipped on the CD then you can easily play them straight from the CD whenever you want to watch them. Another advantage of this is that it means your avi’s are backed up (it’s possible that your computer’s harddrive might be lost in the future).
Apples and Oranges is right. I resize the videos too, so that they’re downloadable from a website. I wasn’t talking about still being able to view vids at DVD dimensions (or quality).
Even so, I can’t see why it would take so many hours (and I don’t really have what could be called a particularly optimum speed computer beyond a ‘latest specs’ PC).
Yeah, I know. I even have a CDR and everything. I’m just cheap and was hoping I could get like two on a CD at a time. I guess that’s not possible without losing quality though.
I have done this many times with an AMD XP 1800+ and it takes quite a few hours. Of course it depends what you are actually doing so you need to give more details. For me the process is
1 - Rip VOBs to disk (DVDdecrypter) - 20 mins
2 - Create DVD 2 AVI job file (DVD2AVI) - 20 mins
3 - Create sound track file (Besweet) - 20 mins
4 - Convert video to VidX 5 AVI using two passes (VirtualDubmod) - 6 hrs
5 - Merge sound with video - 5 mins
Some steps take longer than other but they all take time. The times I have stated are just ballpark figures off the top of my head. Step 4 can easily take 3 hrs per pass and that makes it a total of 6 hrs. An that is only one step. The others also take quite a bit of time although not as much.
Now, if you say you are converting to AVI in a matter of minutes, I do not think you are using the same process in a faster computer. You are probably doing something entirely different. There is just no way the DivX 5 codec will encode a whole movie in a matter of minutes on any computer. So you need to tell us exactly what you are doing .
First - I never said anything about ripping DVDs. Second - neither did the OP. Therefore my assumption was just as far as ‘compressing an AVI’ which for me the procedure is:
[ul]
[li]Capture an hour of DV from tape - 1 hour[/li][li]Edit in Premiere (including titles) - Anything from 2 hours to about 3 days[/li][li]Output into raw DV (13Gb per hour) - realtime, about an hour[/li][li]Re-import into Premiere - 0.5 seconds[/li][li]Compress into low resolution DivX AVI - approximately realtime, 1 hour or so.[/li][/ul]
In fact I usually edit down to 4 - 5 minute clips, but the principle is the same (I have made DVD-ready videos before, but they don’t need to be compressed). As I mentioned, these are for downloadable clips on a website.
OK, I took a 93 minute, 672*352 pixels, 700MB AVI, movie file, and I am re-encoding to DivX 5.0.5, using the same resolution, two passes, right now, using Gordian Knot . Ignoring the time it took me to set up the whole thing, ignoring the audio part etc, strictly the video re-encoding, is estimated at 1 hr 45 mins per pass which is a total of 3.5 hrs. When I did the same movie from VOBs it took twice as long. I suppose having it in AVI already is an advantage. Still, I just cannot see how any computer can do this job in a matter of minutes. Again, I am using an AMD XP1800+. Add the overhead of your time preparing the whole thing and it does take a lot of time. Then add the wasted time for the times when something went wrong and you have to redo the whole thing over again.
Well. I don’t know what to say. The longest something took for me was nearly three hours for an hour-long video, but that was because I was trying to compress something that had a lot of transitions and video tricks and stuff on it, which slowed everything down.
I also do a single-pass CBR, because for what I do VBR doesn’t seem to improve things a great deal; in fact it seems to make the files larger, which I try to avoid.
clap clap
I looooove bad jokes! 
What do you mean by this? Are you getting low on disk space?
If disk space is not a problem, perhaps you just need to defragment your drive. A contiguous 650 MB file shouldn’t cause any problems in and of itself.
I’ve gone from AVI to MPEG trying to make VCDs, and that process itself takes FOREVER. I’m sure that recompressing AVIs and changing AVIs into MPEGs are similar, and since the latter took me ~8 hours for one ~700MB movie, I assume they both take a really long time.
Maybe it’s time to check your job description, Guano?
[QUOTE=GuanoLad]
[li]Compress into low resolution DivX AVI - approximately realtime, 1 hour or so.[/li][/QUOTE]
What do you mean by “low resolution”? DVD’s that are converted to DivX aren’t low resolution… e.g. for me, one was 640x256 and the other was 640x352 with high image quality. With two passes and variable bitrate it makes the final video as compressed as optimally as possible (so it is highly compressed, but with the best possible image quality). DivX has heaps of settings, you might have used settings that didn’t cause it to take long to encode.
Yeah, I’m getting low on disk space. I use the files for various things, and it’s easier for me to keep them on the harddrive, rather than burn them on to CDRs. I was hoping I could find a way to either compress the files to the point that I wouldn’t have to put them on CDRs or put more than 1 file on at a time.