Two DVD-9 videos on one DVD-5 disc with good quality?

[varied]

Hi to all!

I even don´t know how can I find what I want to know, so I´m really sorry if this was asked before!

Let´s assume I have 8 dvd-9 movies. My goal is to rip them on 4 dvd-5 disks (2 movies on one dvd-5 disk). Of course, the easiest way is to make a two pass encode to compress each movie to the size of one half of dvd-5, but each movie has different length and noise level and so forth. So its not fare, because some movies will look better than some others. So what I want to know if there is some way to calculate appropriate size of each movie. What more, I want to know if there is way to find best pairs of movies, I mean, its better to have one long(noisy, contrasting) movie and one short(smooth, monotonous) movie on one disk, and not two short (smooth, monotonous) movies on one disk and two long (noisy, contrasting) movies on one disk.
In short, I want computer to find best pairs and appropriate size for each movie, and pair of movies should be dvd-5 in size.
I have only one idea how to do that, but a lot of decisions I have to make my self and it will take some time to accomplish. So here it is,
join all movies into one real huge movie (with avisynth, for example). Than convert this to size of 4 dvd-5 disks. Than split this huge movie back into 8 movies. Next choose best pairs, so all the pairs are as much close to the size of dvd-5 disk as possible. Than take each pair and calculate percentage of each movie of the pair and next just apply this percentage to the size of dvd-5 disk.

Hope, the question is understood. And sorry for my English!

And thanks for Your opinions in advance!

[manono]

Hi-

In short, I want computer to find best pairs and appropriate size for each movie, and pair of movies should be dvd-5 in size.

I do similar things all the time, putting a number of TV episodes on a DVDR, each with equal quality. As you know, using the same file size for each episode will give you episodes with differing quality. The problem becomes even greater when movies are involved.

However, first I would say that I wouldn't put 2 movies on a DVD5. The quality in any case, no matter how you do it, will suffer greatly, as your average bitrate might be around 2500 or so. If you insist on doing it, I'd use a low bitrate quantisation matrix to try and limit the damage.

Since you seem to know some AviSynth, then open an AviSynth script for each movie in your encoder, encode them each for the same quality (a 1-pass CQ encode), compare the file sizes of the resulting MPVs, and use those sizes to then choose the movies to go on each DVDR, and the relative sizes of each. That's how I do it.

Your English is fine.

[jagabo]

This seems like an ill conceived idea but I guess you have your reasons...

You could run a constant quality encode on each movie individually. The size of the resulting MPEG files will give an idea of each movies "compressibility". Then pair them up as you described.

This is similar to what happens with 2-pass VBR encoding. During the first pass the movie is encoded at constant quality to see how compressible each frame is. During the second pass that information is used to allocate bitrate througout the movie.

LOL, manono beat me to it!

[manono]

Strange, eh? Pretty much the exact same advice, but using very different language.

[varied]

After all, I did one mistake, I didn't say I want to rip to xvid, not to mpeg2. So I guess there's no need in low bitrate quantization matrix.

I didn't think about 1 pass quality based encode and yes, there's no need in joining movies and so forth. That's just because I actually never did what was in my question. It is still the same thing, firstly I should convert all movies with constant quality (its like the first pass), and than decide what pairs and what size to apply (second pass). So there's no way to do those two passes by a program, that's what I needed to know, and now I know it! Thanks to both! Sorry for bothering!

[jagabo]

I would try encoding all the movies at target quantizer = 3 and whatever frame size you plan to use. That will give you pretty good quality and the files will probably be small enough to all fit on 4 DVDs without having to encode them again.

[varied]

I know, but that is just an ill conceived idea...
For me, 3 is enough for some movies, but there are some movies which are 1.2 gb in size with 2 hour length and quantizer = 2 used, and blacks there are so blocky (for example, Unleashed and Last Action Hero)

Edit: And "Alfa Dog" with quantizer = 2 is terrible!

[jagabo]

If you see lots of macroblock artifacts in a movie encoded with Xvid at Q=2 they were in your source. Use a deblocking filter.

[varied]

"Alfa Dog" rip was made from real HD DVD source, I thought I did some thing wrong but I rechecked several times codec settings, and the same setting produced very good result with "Transformers" (quantizer = 2). Maybe its because "Alfa Dog" is quite dark film, and dark areas are not so important for encoder...

Edit: I guess I answered myself to question I haven't asked yet , I need to apply different quantization matrix (for movies with low contrat) to such films like "Alfa Dog"

[jagabo]

Try encoding without using B frames. B frames are encoded with higher quantizers so they get more macroblocks. Of course, your files will turn out larger.

[varied]

Thanks for pointing out! Never was good at frame types. (need to learn)
Will try without b frames and with different quantization matrix. Or it will be enough to just turn b frames off?
Anyway need to try all variants. And thanks again!

[jagabo]

Thanks for pointing out!
Will try without b frames and with different quantization matrix. Or it will be enough to just turn b frames off?

Just disabling B frames might be enough. You should experiment changing one thing at a time so you can isolate what effect each change has.

[varied]

Yep, I thought just like that, and that's what I'm going to do!
Really appreciate Your help!

[halsboss]

DVD's are cheap. wasting your own time.

[redwudz]

varied, in the future please use a more descriptive subject title in your posts to allow others to search for similar topics. I will change yours this time. From our rules:

Try to choose a subject that describes your topic.
Please do not use topic subjects like Help me!!! or Problems.

Thanks,
Moderator redwudz

[SmokieStover]

DVD's are cheap. wasting your own time.

Amen!