Shrinking twice with DVDShrink

[lal]

I was trying to backup a 2hr 45 minute movie with LPCM audio. But I was
not able to put it under 4.7GB limit even with "level 10" compression.
So, I compressed once with level 10 and compressed the backed up
copy again with "level 2" It worked up fine and I was able to fit
it into one DVD. I had to compromise on quality though. It wasn't that
bad.

The other thing I notied, for some DVDs, DVDShrink is not showing
more than "level 5" option. Anybody know why?

[tompika]

I think shrinking two times on lower level (3 or 4)
can give you a little bit better result than doing it on level10 and then level2

[lal]

I'll try that tonight.

[Alan69]

I'd say try even further the other way. Here's why..

Say 10 first then 2, as you did. The 10 compresses as much as it can off the full info, but then the 2 pass doesn't have the depth of info to decide what won't impact the picture. Even though it's only doing a little more compression, the picture has already lost most of the orignial info to make decisions from..

2 first should only drop out the least useful picture info. Then a 10 pass on that still has most of the original picture info to calculate the best data for each pixel. Should give a noticably better result.

But it really depends on exactly what the compression is chosing to drop at each level, so try all three ways (10-2, 4-4, and 2-10) and find which is best for the particular compressor. But if a light pass just drops noise and useless picture info, then a 2 then 10 should do the best, the second 10 still has almost all the picture data to work with to do it's best.

If the compression were totally neutral, then you'd get about the same results regardless of which way it was done once you get to similar file sizes. Since it's likely to be weighted in one way or another though, one of the three ways (heavy first pass, even, and light first pass) is also likely to produce better results than the others.

Alan

[lal]

Alan,

Thanks for the explanation. I'll try all the three ways. The first way (10, 2)
was marginally better than a VCD. I've to test the other two ways.

Thanks.

[DVDJunkee]

Just a thought but isnt there a way to transcode the audio to ac3 and save a bunch of size there?

[Faustus]

DVDJunkee: Yes baldrick has a guide in the guides section on how to convert different audios to AC3, it saved a ton of space over LPCM, I ran into this just last week.

[DVDJunkee]

I thought I had seen something about that around here.

To lal: Try out that guide and save space on the audio as well.

[thayne]

If I were you I'd star over.

Rip the original DVD with SmartRipper in stream processing mode. This separates the mpeg video and audio into two files.

Then run the audio file through BeSweetGui to convert to ac3

Then reauthor the ac3 and mpv file with ifoedit to create your DVD files.

Then run that through DVDShrink

There should be guide here telling how to use each app, or at doom9.org

[lal]

Thanks for all the replies.

If I rip the video and audio seperately and then convert the audio to ac3,
wouldn't the final DVD has lip sink problems? Or is it taken care of with
the mentioned tools?

[DVDJunkee]

If it is done properly it will not have any sync problems.

[Gregg]

Hi,

I tried once to compress a movie with DVDShrink twice at level 3 and ended up with horrible results. Maybe the bitrate of the movie was too low I don't know.
As far as replacing LPCM with AC3 is concerned it can be done and will work with a regular movie/movie only/. But what if you have a music DVD with multiple menues and song selections and stuff? I was thinking of reauthoring but it will consume so much time that it would be better to buy the damn thing.

Enjoy!

[lal]

I did the following way and got fairly good results.

1. DVD2AVI - to rip video and audio streams seperately
2. TMPGenc - to encode the above into mpeg2 format
3. TMPGenc DVD Author - to create dvd structure (menu, vob files)

Thanks for all who replied.

[Gurm]

Please tell me you didn't rip it all the way to AVI and then convert back to MPG?

- Gurm

[lal]

Gurm,

Not sure whether I ripped all the way to AVI. I used DVD2AVI and
followed the guide for it posted on doom9. The only thing I didn't
follow from the guide is downsizing the audio from 48 to 44.1 KHz.
It produced ".d2v" and ".WAV" files which I converted to mpeg2
using TMPGEnc.

Thanks.

[Gurm]

Ok that's fine. People recommend using DVD2AVI a lot, but if you aren't careful it tends to finish the process and go all the way to AVI which is absurdly time consuming and quality-lossy.

- Gurm

[lal]

thayne,

I am trying to redo this DVD by converting LPCM audio to AC3.

1. I ripped using Smart Ripper in stream processing mode but it created
to video files and one audio file. So, ripped the movie again by creating
a single vob file (using Smart Ripper).

2. And then used TMPGenc to demux (used MPEG Tools -> Simple Demux)
and got one video and one audio (.WAV) file.

I'll follow Baldrick's guide to convert WAV to AC3. Now, how do I mux
the video and AC3 file using IFOEDIT? Do I get and mpeg2 after that?
Can you point me to any guide?

Thanks.