What software to compress DV-AVI?

[Velojet]

I'm wanting to compress DV-AVI files for backup storage, using the DivX or XviD codecs.

What would you recommend as the best/simplest/cheapest software to do this? (I realise that you might not get all three in one app!)

Thanks!

[Video Dude]

Welcome to forum. As per the rules, there is no best.

Two programs you might want to look at:

http://www.virtualdub.org

or

http://labs.divx.com/DrDivX

[bb]

I'm wanting to compress DV-AVI files for backup storage, using the DivX or XviD codecs.[...]
Be aware that MPEG-4 is not ideal for editing. If you plan to edit you backups later, I recommend to keep it on DV tapes.

bb

[Velojet]

Thanks for your handy hints, Video Dude and bb.

I've now downloaded and tried VirtualDub (I'd heard of it for editing, but didn't think of it for compressing, but it does seem to do just what I need it to do) ...

Which is simply backing up my DV tapes (stored offsite) after editing and burning to DVD, so that if disaster befalls them, at least I've still got an acceptable facsimile of the original video.

I've now also tried editing the compressed files (in Ulead Movie Factory 5) and the editing seems to go OK. What makes it "not ideal for editing", bb? (apart from the reduction in quality).

[bb]

All MPEG formats use P- and / or B-frames besides I-frames. The latter are comparable to DV frames (or JPEG pictures), wheras the other two store differential information only. Thus you have to deal with "groups of pictures" instead of single pictures, and editing is more complicated, time-consuming, and error-prone. During editing loss of quality is much more evident than with "single frame" formats like DV or MJPEG.

bb

[Velojet]

Many thanks, bb, for such a lucid and helpful explanation. Clearly, editing the DivX MPEG-4 backup files would have to be a last resort.

[bananacreamandpeca]

Now something that is not so lucid/clear:

what these guys dont tell you is that compressing DV content to xvid gives very bad results (I think anyways)
I own a sony d8 camera myzelf, and home made material.
A girl riding a horse for example will not compress well to xvid.

Why? The guys around here say its because the video will be too shaky (handheld content)
for the coedec to handle well.
Wich results in high bitrate needs for the codec during encoding.
Wich means your homemade video material will not compress and
give the same sharp results as when you rip a hollywood dvd-movie
And convert that with xvid.

Try it yourself, quality stinks uless youre prepared to do alot
of postprocessing (wich means you dive into the world of nerds and their avisynth etc. and use alot of filters, not to mention alot of different utilities and programs
to try to enhance the picture before you compress it)

The best way to preserve your video-content quality is to copy it to your pc.
Make sure you use copy dv-ontent in d8-quality when you move the content to your pc.
Edit (only cutting) it up the way you like (kick out unwanted material etc.)
Then re-copy it to a digital tape/your camera, and save that.

It will be digitally stored on tape anyways. So loss of frames as with analog vhs etc.
wont be an issue (i think)

[bb]

[...]what these guys dont tell you is that compressing DV content to xvid gives very bad results (I think anyways)[...]
Not that we won't tell our secrets ;)
Whether you'll get "very bad results" or not depends on a number of factors.
[...]The guys around here say its because the video will be too shaky (handheld content)
for the coedec to handle well.
Wich results in high bitrate needs for the codec during encoding.
Wich means your homemade video material will not compress and
give the same sharp results as when you rip a hollywood dvd-movie
And convert that with xvid.
[...]
Again, there are a number of factors affecting quality. Not only that the video may be shaky, but also that DV content is interlaced most of the time, and that you have to deal with noise (especially in low-light conditions). To achieve good results, some filtering is recommended before compressing to MPEG-4.
Homemade DV content is not as compressible as DVD content, that much is true.
[...](wich means you dive into the world of nerds and their avisynth etc. and use alot of filters, not to mention alot of different utilities and programs
to try to enhance the picture before you compress it)
You don't have to be a "nerd" to use AviSynth, if you ask me. Using different utilities and programs should be common to the video hobbyist :)
The best way to preserve your video-content quality is to copy it to your pc.
Make sure you use copy dv-ontent in d8-quality when you move the content to your pc.
Edit (only cutting) it up the way you like (kick out unwanted material etc.)
Then re-copy it to a digital tape/your camera, and save that.

It will be digitally stored on tape anyways. So loss of frames as with analog vhs etc.
wont be an issue (i think)
There are other threads on this forum that focus on DV backup / archiving. Please use the search function; you'll find many topics already covered.

bb

[Velojet]

Thanks for your input, guys. I started this thread because I was simply looking for a knowledgeable steer towards software to handle my DV tape compression/backup, out of the plethora of products out there, and I couldn't find a thread here that focussed specifically on that issue.

However, having done some tests now with VirtualDub, I looks as though that'll do me ...

There are other threads on this forum that focus on DV backup / archiving. Please use the search function; you'll find many topics already covered.

... and now I'll check out those other threads for advice on handling the process itself.

Thanks again.