Editing MPEG-2 Files

RichMitt wrote on 2/11/2005, 10:38 AM
We have compiled a wedding into three separate projects in Movie Studio 3, which have now been successfully rendered into MPEG-2 files. As per Forum members recommedations, I plan to upgrade to Movie Studio 4 so that I can author the files into a single DVD.

I now find that I have duplicated about five minutes of footage on two projects. Can I cut out one of those segments when I do the authoring process? Or do I have to cut it out in Movie Studio and re-render one of the projects (which unfortunately would be the "overnight" one)?

Comments

Steve Grisetti wrote on 2/11/2005, 11:36 AM
MPEG files don't edit well, Rich. Because they alternate between master frames and frames based on master frames (part of their compression systerm), when you cut any frames you end up with a corrupted or flickery video.

You can convert the MPEGs back into AVIs using a program called VirtualDub but, because you're going from a highly compressed file out to a lightly compressed file and back again doing this, it should be your last resort.

It sounds like you were wise enough to keep your project files or original AVIs around. If so, it would be best to do your editing with them. Even if it means rendering overnight again, in the long run the results will be well worth the extra effort.
gogiants wrote on 2/11/2005, 1:25 PM
Grisetti is, as always, right on with the comments.

I did notice that it sounds like you just need to cut out one scene. In this case, especially if it's to cut out the last few minutes of a single MPEG-2 file, you shouldn't see dramatic effects. If you cut and spliced together a lot of scenes you would likely notice.

Also, by cutting out the one scene, you'll likely have to "re-render" but since you'd be rendering from MPEG-2 to MPEG-2 it likely wouldn't take nearly as long.

All that said, if you do have the original AVIs it might be worth having a "perfect" DVD if it is someone's (your?) wedding!

People have mentioned that you can have "exit points" in clips in DVD arch studio, which would bail your viewer out of the clip. But, I've never tried it.
trock wrote on 2/11/2005, 5:28 PM
There a few ways you can edit MPEG files without re-encoding but they all need external programs, a couple of which are free.

Mpeg2Schnitt and Cuttermaran both enable you to do simple but frame-accurate cuts and then save without re-encoding and both are free.

For more sophisticated MPEG editing without re-encoding there are VideoReDo, MPEG-VCR and TMPGEnc MPEG Editor, all at around $50. They only re-encode any changes (like transitions or new effects - anything other than simple cuts).

For the ultimate in MPEG editing there is MPEG Video Wizard which has multiple tracks, transitions, filters/effects, titles, works with AC3 and has MPEG repair tools etc. etc. It's a bit pricier at $120 but does a great job. It also only re-encodes the changes so saving is very fast.

After you've done your editing, you click on render and it shows you graphically what and where will be re-encoded and what will be left as it is. If you've just done cuts, nothing will be re-encoded. If you've done any transitions, just those will be re-encoded (and very quickly).

Then you just re-author and re-burn.