Is mpg joining possible without re-encoding entire timeline

scottb721 · Post by **scottb721** » Sat Oct 13, 2007 3:32 pm

I've stripped mpegs out of VOBs that were already on some DVDs.
I'm joining the mpegs together and creating a 'movies through the ages' clip. The mpgs are already DVD compliant but each one would have a different bitrate as that varied with each source DVD.

My question is - Is there any way to have MSP8 create my new DVD destined mpeg without having to re-encode the entire timeline, but rather, only encoded sections where I have added transitions between the mpegs and do a copy/paste of the unaltered portions?

A test seems to show that it's re-encoding all to the project's target rate.

Thanks for any suggestions.

Devil · Post by **Devil** » Sat Oct 13, 2007 4:06 pm

I haven't tried this, but I would guess it would be unlikely unless the source and project settings were identical and Smart Render was on.

Again, without trying it, I suggest the only way of doing this may be not to join them together in a single project but to have each clip as a separate title in an authoring application which would accept compliant files without re-rendering. With DVD Workshop 2, for example, you could arrange the playlist so that the titles played successively in the order you wish, but there would be a very short pause between titles, probably hardly noticeable, depending on the buffer memory in the player.

However, I emphasise that this is untried, so please do a trial first to see if it works.

scottb721 · Post by **scottb721** » Sat Oct 13, 2007 4:17 pm

Even with Smart Render selected it seems to give the whole thing a going over.
But I get your drift about keeping them separate and authoring them that way. Pity the "do not reconvert compliant mpeg" checkbox isn't available in MSP in the DVD template settings.

Cheers

Helge · Post by **Helge** » Thu Nov 01, 2007 10:44 pm

Would be a very nice feature for MSP9 (beside of removing the most stupid bugs). Even if you only cut off a little bit from the beginning or the end, MSP8 will only "render" quickly, if you happen to figure out the exact properties of your input video and use the same for create file. (This is possible, but tedious.)

troppo · Post by **troppo** » Fri Nov 02, 2007 1:12 am

Unfortunately smart render is just not smart enough!

scottb721 · Post by **scottb721** » Fri Nov 02, 2007 6:15 am

Turned out the rerendered mpeg still looked good.
The ugliest part of it were the clips that came from NTSC DVDs. My timeline consisted of both PAL and NTSC and I was outputting to a PAL DVD.

sjj1805 · Post by **sjj1805** » Fri Nov 02, 2007 6:22 am

That is due mainly to two reasons.
a. Frame Rate. NTSC is just under 30 frames per second whilst PAL is 25.
This means it had to effectively dump 5 frames every second - that would obviously make things a bit jerky.
b. Screen size.
PAL is (normally) 720 x 576
NTSC is (normally) 720 x 480
Although they are the same width they have different heights, so the NTSC would be stretched to make things taller.

scottb721 · Post by **scottb721** » Fri Nov 02, 2007 8:03 am

The slight difference in AR wasn't too bad but the jerkiness was not acceptable, for me anyway. Of course those that saw the final product thought it was great and couldn't tell the difference by that's hardly the point now is it! lol

But it taught me a few things, including making sure it's the 2ch mix that's extracted from the vob with the video. Using the 5.1 audio caused a few headaches with audio filters.

deklerkt · Post by **deklerkt** » Sat Nov 24, 2007 1:29 pm

My understanding of SmartRender to work, your project needs to meet the following requirement:

- all parts encoded by the same MPEG encoder
- the project setting to have the same or higher bitrate setting than any of the parts
- audio to be the same for all parts and matching the project setting
- all parts PAL or NTSC but no mix and the same as project setting
- all parts same Upper/Lower field settings and matching project setting

This also applies for File > Create Video menu.
Any deviation from the above results in the deviating parts to be re-rendered. And converted from PAL to NTSC or vice versa. And the latter never looks good.

Theo

MrA · Post by **MrA** » Sat Nov 24, 2007 4:32 pm

Have you tried DVD Work Shop or the latest Movie Maker? If it's already an Mpeg why use a video editor?

deklerkt · Post by **deklerkt** » Sat Nov 24, 2007 11:52 pm

Fom the original statement I gathered he was composing a new DVD from little bits of film. If you want to combine these (with titles, transitions etc) you may want to use an editor before using DWS as that would make all parts a title and the title-transition is always noticeable.
But even if you did, different sources in DWS would also make SmartRendering impossible for most or all of the titles.

Theo