Multiple DVD streams onto 1 CD ?

[iparout]

hi there.

I am experiencing the following problem when using GKnot 0.26 to rip DVDs.

I have a DVD with 6 episodes from the famous TV-Series "Friends" and I want to rip them to CD. Each episode is 22 minutes long and thus I have chosen to compile 4 DivX episodes (88 minutes approx.) in 1 CD using DivX.

The episodes appear as different streams (VOBs) when I open the DVD with Smart Ripper i.e. each episode is a different stream. I have ripped all 6 streams off the DVD and I now want to encode each stream (=episode) to Divx.

Since I want to have 4 episodes on an 700 MB CD, I have to dedicate approximately 150 MBs to each episode. When I open the d2v file of a specific episode, under the Bitrate tab, I enter the filesize manually (170 MB instead of 1 x 695 MB) and GKnot calculates an average bitrate of 940 kbps.

The problem is that using these settings, the Bits*(Pixels/frame) value is as low as 0,123 and I also get a very low result of 25,3 % after the compressibility check. The output DivX file is not very good either.

I have ripped several DVDs to Divx in the past and the output quality was excellent, however those DVD movies were 1 stream and not 6 like with the "Friends" DVD. While ripping other (1 stream) DVDs in the past, I could go as low as 800 kbps however the quality indicators would be about 0.17 and 47 %.

Why now, although I use 940 kbps, the quality indicators are low and the output quality is not that good as it used to be ?

I have the feeling that GKnot works perfectly when I choose 1 x 695 or 2 x 695 MB e.t.c in bitrate calculation, however when I *manually* set the desired filesize of the output Divx (as needed when you want to add more than one DVD streams to a DivX CD), something happens and GKnot doesn't yield that excellent results anymore.

Is it a bug or sth or am I doing something wrong ?

Thanks in advance.

[UncasMS]

could it be an resolution problem or at least be related to the resolution?

friends will be 4:3 (or not?) and most movies should rather be 16:9 which will result in better Bits*(Pixels/frame)

[uklawman]

As UncasMS has already stated, changing the Resolution will indeed make a difference to the quality of your episodes, however, there is more you can do..

Firstlly. each episode will take up different amounts of space depending on how well it can be compressed, therefore a 700mb cd divided by 4 = 174mb per episode.
With this in mind you could set your *filesize* higher or lower in conjuction with the Screen Resolution size to achieve a *better* Bits*(Pixels/frame) value for your episodes once you've performed the compression check.
Another point worth mentioning here and one I would also consider, is that you can encode your AC3 sound file so it uses a lower MP3 bitrate, which would save you a few extra MB for your Video if your not too fussy about sound quality?.

However, I personally would convert each episode into a .ogm file and have great sound and high quality video in the least amount of space.

Hope this helps?

[iparout]

Thank you both for your replies...

I haven't thought of what UncasMS said about the episodes being 4:3 and thus resulting in a low bits*(pixels/frame) ratio. That's a very good point...

I tried lowering the output resolution from 640x480 to less and the bits*(pixels/frame) ratio increased, however I didn't notice any visible difference in quality (I play my movies on TV using TV-out).

I will keep it as it is and I will compromise with the poorer quality... (It's not that bad after all... )

Thanks again.