DVD Rebuilder v Nero Recode at Low Compression

[apfraats]

i can trust but could be better encoding the whole cells together and not one by one???
i think because:
why not if encoding the whole cells for better distribuitions(VBR)?
take a look here if you don't understood what i mean: http://forum.doom9.org/showpost.php?...2&postcount=19

please explain me why, i need to understand.
thanks.

Becuae I mentioned this too by JDOBBS and he was saying CELL by CELL was the same as doing whole at once or even better........

Because it's VBR it won't matter. Of course I didn't agree but a lot of people did.

If the motion is relataive to cells, there is no problem, but what if a cell 1 and cell 2 conatains a common high motion high action scene ????

And for the rest are slow-bitrate ?

Jdobbs stated it won't matter because of the VBR used. The encoder would automatically go up in bitrate at the end of cell 1 and the beginning of cell 2....

So in fact it wouldn't matter.........

I think there is some truth about this because a good quality real-time encoder doens't even know what comes next... (They look just a small part ahaed so heaving many many more 'cells')......But then again they are almost everytime CBR.....

SO I don't know.......

However most people think it's ok the way it works.....

[jeo]

explain what?

now you need explanations,sorry.
let me try using as example of one dvd-9 that have only 2 cells.
if the first cell have 7Gb with low action and the second cell have 1Gb with extreme action, i ask:

why is better encode this dvd-9 cell by cell and not the whole cells together to get one dvd-5???

thanks.

[jeo]

i read the last apfraats(very cool) post now and i don't agree with Jdobbs explanations for the same reasons
ot
after post in doom9 the same(seamless) a long time ago and i was "striked"

ot off

thank you apfraats, you got the feeling!

[UncasMS]

http://forum.doom9.org/showthread.php?t=94683

[jeo]

ot
here was not an answer,only one oppinion:"I would disagree..."
because(real reason?) "...it would definitely reduce the capabilities of the package."
ot off

jdobbs explanations are good about the "prepare fase-first pass" but reading fishman0919: "...per cell allows you to stop the encoding process and restart later"

stoping the process and restarting later,is the first scan(prepare fase) of the entire mpeg is used again?

[apfraats]

If it is possible to do the whole DVD at once (if you don't exceed some limit such as cell-lenght ot size) it would be the best.

I never new why cell based should be 'best' .
I think it doen't matter that much, as it's up to the encoder to do good work.

But from tests I have done, I still have the impression I get a shortage of btarate in some sudden high original bitrate scenes, especially if they are just a part of a cell. A low average will be set, and the encoder has to go up from this average to the max bitrate neeeded. Even with VBR_BIAS=0 CCE can't sometimes keep up as it seems, nor other encoders do.....

By the structure DVD-RB uses it is almost impossible to do it on another basis. The segment/cell structure is the core it's build arround.

However I have the 'feeling' when you divide the DVD in parts by a heuristik algotirhm of some kind that makes segments of BITRATE alike parts that can be grouped together , so if significant parts are detected with clear different averages, this would be better.......


But they say it won't matter........

However all I notice is that still everytime the high motion scenes become in trouble.... Never a low action scene has too little bitrate, as seen with transcoders sometimes.

So for some reason there is not enough emphasis on the high motion scenes that demands more bitrate....

As long as bitrate distribution is kept in CELL boundaries, there is nothing wrong with the appoach.

Even not having two cells, CELL A having 2500 average and cell B having 6000 average. (if w're playing black white, I go along with it )

The problem comes when both cell A and cell B have the same action, high motion scene. (take for example a 9500 bitrate 2 seconds lasting scne) This scene will be better of in cell B then resting in CELL A, as simple as 1+1=2.

So if you compress such a dvd bij 50% it will be averages of 1250 and 3000, and the scene in cell A would suffer greatly........ The same scene in cell B would suffer less......

So that's probably the problem. The average bitrate...... and the meaning of cell boundaries with have nothing to do with bitrate at all.

The above example is not very realistic, but could be made......


Just to show how sudden high motion high action scenes can get snowed in from much longer lasting low action lower bitrate scenes....
And if that's happening in a cell were there is a low average it's verry difficult to reproduce when you have compression....., even without compression just reencoding our example cell based would give problems in cell B....


This would'nt happen with a bitrate alike based algoritm as the two action scnes would be noticed.

[blutach]

Gentlemen,

Please remember RBOpt's great features in this regard if you are worried. Most DVDs split a cell at a distinct scene change (except for stupid ones like Mulholland Drive).

I invite you to do a copy of something like The Last Kiss Goodnight (which has a lot of sudden high motion scenes) with any encoder - even CCE basic - and look at the result. After the prepare phase, check out what RBOpt can do to help out a bit (if necessary) - however, this is just a little tweak, as a commercial movie's bitrate is typically well spread to begin with.

Regards

[apfraats]

I know, it was a academic example as you will not find such a DVD, but it's about the tought.

And manually tweaking a DVD for it's action scenes that get underrated in bitrate is like shooting the movie myself........ not an option......

But in practise it works, just only always having problems with the high motion scenes such as a screenwide helicopter that is flying by in 3 frames....

But often the source is already blocky on these scenes, and if not they will get in the backup......

Then again you'll notice only with pause or stills , not when playing back at normal speed.....

(you see a dark flash from left to right for example, and have no time to notice blocks).

[jeo]

some months ago i read that dvd-rb encode cell by cell...

i'm back to the egg.

UncasMS,
i'm sure that is better post it here than openning a new thread.

encoding cell by cell theme poping up in doom9 again

regards

[UncasMS]

we better add this to it as well.

http://forum.doom9.org/showthread.php?p=740464#post740464

[jeo]

[edited]removing bad impressions,please read my second post ahead

ok you pressed the right key.
i can trust that dvd-rb have great features and have options that no other seamless program can give.i recognise jdobbs work and dedication.
now my negative point of view:look how much stickys have in the dvd-rb forum.for logical reason i start to read the faqs because is the first sticky.
than reading:

Q1. How much do I have to know about all this to make this thing work? If I browse through the options I see a lot of things like quality_prec, deinterlacing, and decombing thingees..

A1. Nothing. Those are all there for advanced "geek" users. After the initial setup...

advanced geek user? it's for me.after initial setup?...have another sticky "instalation,setup and usage" and i think: how the answer in the first question in the faqs is "nothing...for advanced geeks" if have more than 434 replies in this moment only in the stickyes and if i ask why something is wrong,or any doubt about the program,i will get something like:"use the search?!?! how can i find something inside dvdrb forum with more than 30.694 posts after read lots of stickyes and don't find answers inside that stickyes?!??what word can i use in the search to find what i need?
i can't see how use one click after follow that big sticky about setup with lots of corrections.
maybe more than 1000 clicks is needed first to the final "one click"
dvd-rb will be easy to use in the future like dvdshrink or dvd2svcd that are easy too use.
dvd2svcd is really "few clicks",not so powerfull as dvd-rb but you only need to install and use,dvdshrink have lots of options but is very intuitive.
believe or not: i,with horrible english wrote 3 guides for dvdshrink because is easy to use and my single guides don't have corrections.
(this guides are in kvcd forum,vmesquita forum and in doom9 portuguese forum)
geeks like me have to wait "until tomorrow" to use dvd-rb,when asking to remove doubts don't take to "search in this unfriendly doom9 dvd-rb forum" and if answer this or ask again ...you're fired

here my "sin-cere" words because i read lots and i still don't feel secure to install and test dvd-rb for the reasons posted.

regards

[blutach]

Wondering if this should be moved to the rants sub-forum.

Regards

[jeo]

maybe one more sticky to dvd-rb doom9 forum.

don't worry blue,was a single geek post.

regards

[jeo]

gentles,
i change my mind.
yesterday and today UncasMS with great patience give help to use dvd-rb.
i never had used this program before.
step by step i was reading,posting doubts and getting answers until the cool result.
i'm very thankfull to UncasMS,jdobbs for dvd-rb,blutach,Cynthia guide for newbys and the whole great team.

now i think very different and ask:
why have posts with problems using dvd-rb if i,a single user(geek new user),
got good help and my good results in my first try?
(using the free version, i can imagine how better is the full version.)
don't need answers,i never will understand!

all i can say now is so much.

[UncasMS]

1.
you're welcome, jeo

2.
participating in a forum is always a game of give and take

=> you ask a question and provide neccessary information - someone familiar with the problem will answer sooner or later

=> you simply cry for help, dont try to help others to help you by providing those pieces of information - hardly anyone will care or stop answering after a short period of help

3.
i'm glad you finally gave dvd rebuilder a try and hopefully liked the results