Time to rethink about using Vorbis for DVD conversion ?

[ChristianHJW]

Guys .... i'm not overreacting .. just starting a discussion where the journey should take us. It seems that we were thinking of Vorbis and the ways we could use it for our purposes in a pretty unrealistic way. The more we talk to the Vorbis-dev team the more its getting obvious that they neither have the time, the possibilities nor the financial background to tune Vorbis for 5.1 encoding .... and the multilingual approach i had was wrong, or simply not feasible it seems.

So, this brings us to a new situation now, we maybe have to think again about what audio codec fits our needs best. MPEG4 format may be playable in hardware players some day and this one will not support Vorbis, or lets say this is very unlikely .. but AAC does !!

I'd like you to check this very long thread ( well, MaTTer pumped it up quite a bit :D ) here http://www.powerdivx.com/phpbb2/viewtopic.php?p=3457#3457 to get a better impression what i am talking about.

So, discussion mode activated !

I think we all agree we should drop MP3, for various reasons .... but, if we do so, whats the audio codec of choice :

1. Vorbis

2. AAC

3. any other ?

[DSPguru]

AAC is great, but unlike vorbis, it's patented :(.

[ChristianHJW]

Well, as long as i can get and use AAC encoders for free ( and thats the case thanks to PsyTel ) i honestly couldnt care less ... we were using MP3 for ages now and didnt have probs with that ...

[Nic]

But FhG are nice.....Dolby are evil :D

I guess your gonna start pestering Ivan now :D

You may find that with Ivan supporting 5.1 fully may not be high on his priorities... :(

-Nic

[everwicked]

Maybe it's too early for Vorbis to do such things...

A codec is a codec, it cannot be minimised to 5.1 or whatever, especially with it's only pre-RC4.

Just my 0.02 €

[BetaBoy]

Wow chris... After reading that thread it seems a shame that the Vorbis team seems so closed minded about the future. Vorbis seems like a natural progression for us. But if the pieces are not in place the only option is AAC... which because of licensing is not truely an option at all.

I hope that the vorbis team sees the "BIG PICTURE" here and what a true opportunity that they could have if they LISTEN to the community and restructure their roadmap a little bit.

[Doom9]

finally we get some interesting discussion in here, eh chris?

I find it a bit discouraging that the vorbis team doesn't show more interest into fully developing the codec for ripping purposes. But on the other hand we have to see that what we do could be seen as problematic so they might not be very interested in getting to bed with us.. maybe we just need to give them some more motivation... let's say the whole scene sticks together and starts using ogg.. that may be enough leverage to change the odds in our favor.

but everwicked also made a valid point.. vorbis is still young. Maybe the developers just want to have an mp3 alternative for CD rips.. after all that's what the codec is being optimized for atm... 2 channel 44.1khz audio. Though on the other hand.. why put multichannel capabilities into the specs if you're not going to use it?

and if we're at it.. is mp3 part of the mpeg4 specs or do we have to use aac for mp4 streams?

[ChristianHJW]

Originally posted by Doom9 finally we get some interesting discussion in here, eh chris? ... well, this is what i'd exspect from the leading DVD conversion board ... discussion about where the community should move ...
Originally posted by everwicked Maybe it's too early for Vorbis to do such things... A codec is a codec, it cannot be minimised to 5.1 or whatever, especially with it's only pre-RC4. Just my 0.02 € .. you're certainly right here EW, but dont forget that at least it should be in the specs ... or will probably never become reality or be bound by old specs, for compatibility reasons ..
Originally posted by Doom9 I find it a bit discouraging that the vorbis team doesn't show more interest into fully developing the codec for ripping purposes. ... i have to agree here, i'm feeling the very same. On the other hand we have to understand these guys. They are doing all of this without any payment, and their main motivation is the personal interest, and this is not DVD conversion, at least not for most of them ... they are all audio encoding freaks and on Linux it seems :D !
But on the other hand we have to see that what we do could be seen as problematic so they might not be very interested in getting to bed with us.. maybe we just need to give them some more motivation... let's say the whole scene sticks together and starts using ogg.. that may be enough leverage to change the odds in our favor. .... and could help them a lot in the end too !! What Vorbis dev team needs now to be able to develop the codec further is some money if i understand correctly. As the codec itself has a very open license they cant/dont want to make money with it .... so only hardware decoder implementations are left. I was talking to a few guys of dev-team recently, seems as if they have some hardware decoders almost done, so iRiver or whoever could buy the complete Vorbis support from them. Fine, but 1t they have to convince these people there is massive interest in Vorbis !! I supported Benjamin's approach of doing the online petition and 1000 signatures can not be neglected, but will this really be enough to motivate iRiver and Co. to spend money for Vorbis support ?? By using DVD community as a platform it should be easily feasible to get 10.000 people signing the petition !! This is maybe the motivation these guys need to see that we love their codec, and will love it even more if they do a few nice things for us ;) !
and if we're at it.. is mp3 part of the mpeg4 specs or do we have to use aac for mp4 streams? ... i heard MP3 was used in MPEG4 streams already, but this was a hack from PsyTel as AFAIK its not in the specs .

[DJ Bobo]

MP3 rulez! MP3 won't die for a looong while!

And 5.1-sound will remain Dolby Digital, also for a loooong while!

I appreciate the work of the Ogg Vorbis programmers, but I'm afraid, they are wasting their time! only freaks here are working with Vorbis sound, no "normal" user will use it, since MP3 is here, and MP3 is not thaaat bad compared to Ogg, so why should I bother my self for extra 32kbps!? to be cool using ogg!? no way!

[ChristianHJW]

Well ... i'm 35 , but sometimes i feel younger than most of the young people posting here ... why ;) ?

[Apfelstruhdl]

no i think vorbis is for normal users, too. it is as easy to use as lame and it is much better :D . i rip all my movies and audio cds to vorbis(you can go down to around 90kbs for a audio track for movies even lower) the same bitrate in mp3 isn't possible.

VORBIS RULEZ

P.S. -Support for ripping purpose would be great.
-I'm really waiting for the first hardware vorbis cd players, i think i'll get one of those

[canadian_fbi]

i haven't personally ever used AAC so i couldn't really tell you my experiences with it, but i don't really think i've seen it discussed here too much other than in a theoretical capacity. could anyone here who's actually encoded a movie in AAC and/or made a finished muxed movie with it give their thoughts as to the quality and size of it, especially compared to ogg vorbis?

i have to say though that what i took from the various recent posts about the reluctance of vorbis developers is that they're mostly just slow to make 5.1 tracks optimized, and also have locked the decoders and whatnot, making further tinkering by us discouraged. but for me personally, two channels per stream is really all i need, and for this vorbis works great. furthermore we have a great set of tools to use it now. so unless someone shows that AAC is decidedly better, i see no reason to change personally.

[MaTTeR]

Originally posted by bobotns

And 5.1-sound will remain Dolby Digital, also for a loooong while! IMO this is just narrow minded think which is what this thread is trying to avoid. No offense to you bobotns. If marketed correctly I could see no reason at all why a well coded multi-channel codec such as Vorbis or AAC wouldn't storm the market for a few obvious reasons.

only freaks here are working with Vorbis sound, no "normal" user will use it, since MP3 is here
LOL. Are you sure about this? :D :D

I think it's clear Vorbis is a great alternative for our 1CD rips these days for obvious reasons. However, at issue is where do we go from here for our multi-channel needs?

[Nic]

Well I did the whole of Austin Powers in sync in AAC ages ago (it took alot (& I mean alot) of tweaking) (the seeking didn't work though :( )

But the sound was blistering :) MP3 just can't cut it.

-Nic

[ChristianHJW]

Nic, you're the right man joining this discussion !! In fact it was you pointing me to AAC almost ages ago with your nice DSF ... so whats your opinion ... should we prefer AAC to Vorbis for our rips ?
Is 5.1 AAC a sensible thing to do at all, given we have to transcode from AC3 ?
Can we expect hardware support for it one day ?

[SimonSez07]

nic -

i am interested in the kind of tweaking u did to get divx + aac to work. even geting aac to play w/o seeking is better than i can do. I have a copy of ur 'crappy' aac ds filter, and have been trying to get it to work with divx in ogm for a while now (i gave up on avi and mp4). im excited someone got aac to work, and any help u could offer would be great.

thanks in advance

- simon

ps - i would be more than happy to help out with any beta testing or anything u need

[ChristianHJW]

Simon,

lazy nic has never tried to use .ogm format AFAIK , he 'only' created the necessary AAC DSF for it :D ...

Goto 'New A/V formats' forums here and read the corresponding thread. If you still dont manage to get it to work PM Oxp and Chibi Jasmin .. i am pretty certain they will help you !

[pei]

I'm not sure if MP3 is going to die out too soon, it seems to me that there are too many people still using it for audio CD ripping. On the other hand, it seems to be a good idea to kill off MP3 for our DVD ripping needs. MP3 just isn't practical for rips anymore because now days even saving 20-30 megs to put toward video is a BIG improvement in video quality. :cool:

Two channel Vorbis is acceptable to me right now because I don't have a multichannel system. I will be upgrading to a better audio system in the future, and when I do I will expect Vorbis to be supporting 5.1 by then, or I will probably be switching to a different codec that does. ;)

As for AAC, I don't have much input on that subject because I haven't tried it yet, but I will when there is more support for it. :confused:

[Acaila]

only freaks here are working with Vorbis sound, no "normal" user will use it, since MP3 is here

I agree with this statement. Only people who are either audio encoding freaks, or rippers know what Ogg Vorbis is at the moment. Ask any 'normal' person (even one who rips audio CD's) if they know what Ogg Vorbis is and they'll go "huh?". Yes, Vorbis IS a great alternative and improvement over MP3, but it's not known widely enough I think. The Vorbis developers are correct in tweaking their codec for the 2 channel 44.1kHz range, because that is what most 'normal' people will ever use it for. Who uses 6 channel audio except professionals and us rippers? The size of the community using 6 channel audio is far smaller than those using 2 channel audio, so it's only logical to assume that is their top priority.
Don't get me wrong, I would love 5.1 Vorbis to replace 5.1 AC3, but I don't believe the need is great enough to justify the effort the developers have to put into it (from their point of view anyway).

Making the developers aware of the size of our community (posting polls?), could help push the scales, because I think they do underestimate us.

[Nic]

LoL Chris....I will try OGM soon, promise... :) (So much to do!)
(Im sure your hiding when ever I go on IRC..I never see U there :) )

@Simon: Ill get to work on it, ive got to try & put better error correction in the DSF filter to allow for PreRoll of the DSF (i.e. seeking)
(Getting AAC to work in AVI took alot of hacking, of AAC2WAV & muxing...want worth the hassle...)

(I used to try & use it on a certain scene on Blade...Ive probably stil got that...hacked it to work perfectly...even seeking :D )
(But every clip needed special tweaking :( )

-Nic

[Chibi Jasmin]

Originally posted by ChristianHJW
Simon,

lazy nic has never tried to use .ogm format AFAIK , he 'only' created the necessary AAC DSF for it :D ...

Goto 'New A/V formats' forums here and read the corresponding thread. If you still dont manage to get it to work PM Oxp and Chibi Jasmin .. i am pretty certain they will help you !

I am sorry, I can't help...I only got OGM + AAC to work with a lot of seeking/sync problems, just as OxP...

[ChristianHJW]

@Chibi Jasmin : no probs, at least you have managed to get AAC into Ogg with XviD/DivX, this was impossible until recently ...


@all

I had a short conversation with Dibrom of the hydrogenaudio board on IRC today .. i asked him he is aware of any AAC encoder Dll we could use with BeSweet/HeadAC3he .

He replied he is not sure but he is convinced Ivan has such Dll's , but will probably never allow to spread them together with any other application than his own .... of course also because this would be illegal after all :( ...

I will email Ivan to be absolutely sure here, but it seems as if this was a first major downside to using a closed encoder ... i never thought of this before i have to admit :( !

[Chibi Jasmin]

[QUOTE]Originally posted by ChristianHJW
[B]@Chibi Jasmin : no probs, at least you have managed to get AAC into Ogg with XviD/DivX, this was impossible until recently ...


Well, it's of no use anyway, because it has the same problems as AAC in AVIs...

A pity all this MP4-Stuff is not mature. I played a lot with it, mostly getting fucked video, crashes and stuff like that. AAC is not the problem, getting the video to play is the hard part. I gave up for the moment, waiting for things to delevop...

[Nic]

One of the way Ivan hopes to make money is by selling a SDK for the encoding...I doubt he will just give that away :(

However, of course there is FAAC, which we could use, but the quality is not good.

Best for people to just use the little GUI's that interface with the executable....not pretty but that might be the best we can do :)

-Nic

[user]

5 fully frequency equipped and independent channels in one stereo wave/mp3/mp2/Ogg etc.

Do you think that's impossible ?

It is possible.

Dolby Surround Pro Logic (DPL)
full frequencies: front left right
center ( I am not sure, if full freq)
rear: only one channel, freq only up to 7 or 8 kHz
In spite of that since a long time 2 rear speakers have been recommended.

The advance:

Dolby Pro Logic 2 (DPL2)

5 independent channels, all full freq
front left right
center
rear: left and right

You may ask:
What is user telling ?
Why is a stereo wave interesting for DVD-rips, multichannel sound ?

Just because stand alone DVD-player and Receiver/multichannel decoder (which are not the oldest) are only able to play and decode waves, mp3, mp2, ac3, dts
dts wins with higher bitrates, it is not good usuable for our usual purposes.....
ac3 is "original" multichannel and it does not need to get decoded and reencoded to have it on CD-R as mini-DVD or on DVD-R/RW ...
Unfortunately I don't know if in mpeg4/DivX you are able to use it.
One disadvantage is the high bitrate of 384 or 448 kbit/s.

BTW: In near future (even now, look at development !) DVD-R/RW and burners are becoming cheaper and cheaper.
Then perhaps nobody will ask for heavily compressed methods (video/audio) anyway....

A very well compromise keeping 5 channels is : a stereo stream.

Without any problems it is easily compatible to old stereo systems.
And people with multichennal equipment:
With a Logic7 / DPL2 / Circle Surround decoder in your receiver you are able to decode 5 channels out of your stereo-compressed/or not compressed audio-streams.

Even stereo streams from Seventies eg. (at that time I guess producer did not think about ac3 or multichannel) contain useful surround informations... That works very well sounding.

Conclusion:

We would just need at the moment a kind of azid, that carries out the stereo-wave DPL2 downmix from eg. 5.1 ac3 sources.
Then it makes sense to compress with mp2, mp3, Ogg (increasing quality !) this stereo stream containing 5 channels to even lower bitrates than ac3.

BTW: For usual movies the normal DPL downmix of todays azid is well enough, because DPL streams are the second best (after dpl2-streams) to become decoded by Logic7, DPL2, Circle surround decoders.

At ff123.net you can download samples of manually mixed DPL2 waves (compressed with Monkeys ape).

If Dark Avenger and Midas would do some work together, then I can imagine that in short time we will benefit by DPL2 downmixes.

These ones can be compressed to mp2, mp3 or Ogg eg.

I tell you: the sound of DPL2 is much better than old DPL.

(at least I tell it for Harmans Logic7 decoder from own experience).

BTW:

Hifi-Test-magazines have compared that Logic 7 is better than DPL 2 as decoder for DPL- and DPL2- sound streams !!!!!!!!!!

With a very well sounding stereo stream, encoded in DPL2, you need with

mp2: for movies: at least 96, better 128 kbit, for music: 128, nearly perfect for most people 160 kbit!!!!
I use for music in mp2 : 224, but the difference of a 160 kbit stream to original wave is only listenable at difficult sound/music parts.

mp3: here are settings, bitrates well known...., very depending on personal taste, usage ......

Ogg: compared to mp3, you save space.

So for bitrate junkies a DPL2-stereo Ogg will be the best regarding 5 channels !

Remember again:

ac3 is a format that's compressed, for 5 (exactly: even 5.1=6 channels). 448 kbit.
That is clearly less than 100 kbit per channel.

If you remember that ac3 is an old and industrial format, then you recognize that ac3 does not contain best quality in its 448 kbit.

Even mp3/Lame should result in better quality (same bitrate, same number of channels) than ac3, because Lame has had a longer time of development and fine-tuning.

Probably same with Ogg: free format, more time, better quality...

So ac3 does not offer best quality at all.
If DVD-R/RW becomes more affordable, nobody will have interst to decode ac3 and reencode it, becuase this transformation does not improve sound, it saves only space, but on DVD-R that few bits (ac3 is compressed...) you save between one and another compressed format with 5 channels do not count.
What counts is if you have the ability to store 5 channels in 2....
Then a HQ stereo format like mp3, ogg makes sense.
Then you have in 128 kbit/ eg. 5 channels.

(you need a good amp/receiver/decoder, but for home cinema you need it anyway, or it is useless even to talk about efforts of Ogg, mp3, AAC)

So I think that for sound encoding the next important step would be to develop a kind of "AZID.exe 2" that produces DPL2 stereo waves...

[ChristianHJW]

user, the big problem here is that IMHP DPL encoded Stereo tracks sound like crap if you play them on not DPL capable equipment, thanks to the phase shifts they use to matrix the center/rear into the 2 ch track ... this is why i almost always use normal Stereo downmix instaed of DPL downmix when doing a Stereo MP3 or Vorbis ...

[user]

And I say:

It makes no sense to discuss better formats if people do not have minimum home cinema euqipment (minimum: DPL)

So if you do hours of encoding video and audio, then you do it with respect of quality.

And to enjoy the quality you need a minimum hifi-setup.
BTW: even if your hifi setup is stereo, then DPL/DPL2 streams do not sound like crap, because most music on CDDA is sold as DPL (I hope with growing DPL2 parts) .
So everybody with stereo hifi would moan about crappy sound (BTW, there is a lot crappy music in the world...)

Of course it is a compromise.

But for people who do DPL downmix, for these people would be even more enjoyable to have DPL2-downmix.

DPL2 - downmix is IMHO the very best compromise to stay compatible to hifi-stereo, DPL, and/or multichannel setup in your living-room.
And regarding space on CD-R.....

[SimonSez07]

the only reason i thought ogm would be a better format for aac than avi is because aac is vbr (the only way i would implement it anyway).

@nic - in your tests have u been using cbr or vbr aac in avi's

i was under the impression that avi has always had problems with vbr audio (even vbr mp3) especially when it comes to seeking. with vbr vorbis becoming more and more popular, i just figured that this was (one of) the purpose of creating the new ogm av format, so that it would be able to handle vbr audio formats w/o problems that were so frustrating w/ avi.

so ... is ogm better suited for vbr aac or avi??

@chibi - i have had same results w/ sync/seek probs on aac ogm streams

so if anyone gets any success w/ that let us all know! i suspect all we need to do is just wait for nic to finish up w/ his dsf filter and most of these probs will be gone. (@nic - thanks for all ur work w/ this)

about aac encoding. i use the command line encoder from psytel because all the gui's i know of limit ur options, and the only option i really need is the (undocumented) constant quality vbr mode. a psytel dll would be nice, but for now it is not the most pressing issue.

- simon