Hi, there!

I've got a 2 DVD set of a concert (details FYI here). Besides usual DVD video stream it contains 3 audio streams:
LPCM (2Ch) 48 kHz 16 bit
AC3 (6Ch) 48 kHz
SDDS (5Ch) 48 kHz
I've some questions:

1. I want to make an audio CD of it. For this it's best to take LPCM stream, right? Is Cool Edit Pro all right to resample to 44.1 kHz or is there something better?

2. I want to make a security copy (divx avi) of the DVDs for watching on PC, 1-2 CDs per DVD. Normally if I do this (movies) video quality is much more important than sound quality, but this time it's the other way round. ATM I have no surround sound system so plain 2ch stereo is enough. My portable mp3-CD devices made me stick to mp3 (lame aps) for high quality lossy audio, so I've got no experience with ogg, mpc, mp4 ... . My only idea is to use lame api (to avoid VBR in avi) but I'd be happy with less bits used for audio. What do you suggest?

3. Some day I'll surely have a surround system, so I want to store one of the surround streams on an extra CD. AFAIK 6Ch AC3 can be played by any DVD-player/surround system, but what about 5Ch SDDS stream? I never heard of this before. How is it's quality/hardware compatibility compared to AC3?

Thnx

tigre

This thread on HA gives me an answer for question 1: CEP is all right (Settings: 24 bits, quality 999 + 48 kHz noise shaping), BeSweet also.

I'd still be glad to get some information about at least question 2. Searching has led to more confusion so far. I'd like to use MPC (supposed to be best lossy quality), but I don't know if it's possible to use it in video files ... and AFAIK it doesn't work with 48 kHz. So should I use Nero AAC or vorbis? PLEAAAASE HELP! :'(

For bitrate lower than 128 kbit/s, OGG
higher than that, usually MPC & AAC handles pre-echo better than OGG.........AAC has better frequency res. than MPC

EDIT:

donno about "Nero ACC". In HA, someone claim that psyTEL is better than Nero AAC at higher bitrates.

K+K AAC should be the best AAC Encoder until now!

No need to use quality 999. For downsampling, quality 100 is more than enough and faster, also mark pre/post filter. Resample to 44.1 KHz 32 bit, and after that, conver to 16 bit using 0.5 bits of triangular 44.1 KHz noise shaping dither, and ready to burn!

Edit!!: Maybe talked too fast (again)... after some more testing, better use at least quality 350 to avoid aliases of very high frequencies, although difference is probably not audible.

Perhaps you should use SSRC to resample.

(note: the K+K comment must be a joke)

@KikeG...

you pinned the tail right on the ass dude. that's EXACTLY how you get the best quality with cool.

of course, if you can run something like Waves IDR before you down-convert to 16bit, that will add selectable noise-shaping for an even more transparent sound (and disable cools noiseshaping of course).

KikeG - you da man!! B)

After you choose what format is best for your purpoces quality/size wise, there's a q what container you can put it in (for PC playback? did I get it right?).

Regarding vorbis in video (ogg/ogm, whatever) take a look at this and this.

As for mp4 I personally would be happy to have some playback solution that provides faad implementation for audio decoding and option to choose video decoder. Right now we have:
-Dicas (mpegable DS decoder): no seeking yet, you can use ffdshow for video playback but only by manually inserting it into graph (with graphedit or capable player)
-Envivio TV: with this one you are limited with only WMP (or QT, or Real), because it's made as plugin for these players. Site sais there's also a standalone version somewhere.
-Ligos: haven't tried that one yet, it's not free BTW (freeware doesn't rhyme with ligos).
-Philips standalone player: doesn't use DS for playback.

Regarding musepack: here's some info.

hmm, also though i would add... Im pretty sure that both cool and waves noiseshaping is capable of creating a HICD compliant 16bit audiofile form a 24bit source.

that means, if you playback the 16bit track on a HICD capable cdplayer (phillips calls it HQCD now), you will in effect be getting 20bit quality from a 16bit dithered disc.

but there's so little information about either on the internet , other than phillips own component cdplayers, i bet you'll have a hard time finding another brand that can play them back with the extra quality. so whatever, then you get a really great sounding 16bit disc.

and of course, this might not even be possable, i just heard about it a while ago and i've been trying to do that method whenever converting from float to 16bit audio, just in case someone has a compatible player. how it works is beond me, i dont think there's a way to detect a HICD so it's probably part of the DA process.

anyways, i'm goind to tip over, better get some sleeeeeeeeep

@mp4 acm codec....


there's one on RareWares, based on faad probably, but mabey faad2, anyways... it says in the readme that he hasnt gotten it to work with avis yet, just wav files.

anyways, its a start

I have never heard of anything like this. 20 bit resolution from a 16 bit source? If you have an audio CD burnt from 128 kbps MP3, will it also make them sound like --aps?

Sounds very much like a marketing trick to me.

-- Uosdwis

from what i read on the phillips website, most of the current cd players/recorders support HQCD playback.

Im not sure how it works, due to the extreme lack of information on the net, I heard about it a long time ago. But it still ~sorta~ exsists... They arent very forthcoming about the information, especially considering they are trying to get everyone to buy the new expensive SACD players.

the Philips CDR820 supposedly supports playback, I mean it says it can copy them (of course, its a regular 16bit cd) but there should be something with the DA process.

my *guess* is that they are using a 20-24bit DA converter which re-positions information it thinks is noise-shaping, so that some of the missing 24bit resolution can be reasembled. I recall (from a damn long time ago) that it was sposed to sound like 20bit.

I wish there was more information about it.

Thanx a lot for your answers.

@KikeG, Gabriel, jesseq:
I'll use CEP with KikeG's settings for resampling. If they do what their name tells the result will be fine . BTW I need to edit some things (split to tracks, fade in/out) so I can do all at the same time with CEP.


Yes, you did.
The information/links you posted were very useful. I hope I understood correctly:
1. MPC playback doesn't work when it's put in avi or ogg/ogm container because there's no DirectShow playback filter so far. Right? So for *high* quality audio I should use AAC (no resampling required )
2. I should use ogg/ogm container because it handles VBR better than avi. Correct?

As a test I created an mp4 audio file with Nero AAC (VBR Extreme, high encoder quality, LTP Profile). It's 175kbps. I'm glad with this bitrate, but I'm not sure about quality. Can somone tell me what mp3/mpc setting would be needed to get comparable quality - or the other way round: What setting is needed in Nero AAC to get the same quality as MPC standard?

Yup, I edited my previous post, better use quality 350 for the resampling at CEP to reduce aliasing of very high frequencies. Difference will be probably not audible (the aliases are very small and at quite high frequencies only) , but this way the aliases are no more there. Sorry.

Another tip: do all the editing after resampling, in 32 bit mode, and as a final step convert to 16 bit, this way max. quality is retained.

Thanks. Got it. Does this mean the higher the number (350) the better? If so I could use even 999 as I don't care about speed at all here.

Amazing that you weren't flamed to death yet for a 'factual statement' such as this.

HA is growing soft

To sum things up:
-vorbis: you can produce ogm's (which is container, originally designed for video+vorbis) right now, but this one is an unsupported (yet playable) extension of ogg container and it's currently being adopted / merged into Theora project (or beeing dropped in favor of Theora, (?)).
-aac: you can do it right now (by muxing it with video in mp4 container using Nero plugin or mpeg4ip tools), there are plenty of options for playback on PC and also hardware implementations (expected or maybe existing).
-musepack: you have no choice but wait for matroska.

Regarding avi container: there are no (and most likely won't be) any working solution for handling neighter vorbis, nor acc, nor musepack in avis.


Well, this was started about two years ago and it's alredy 'finished'.

I just found this on doom9 (http://www.doom9.org/mp4.htm):

So using AAC audio is no good idea either? The solution seems to be as far away as in the beginning.
What's left? Vorbis?

edit: ak, I didn't see your last post when submitting this. I think you said clearly what choices there are ATM. Thanks.

After a little more testing, with 350 there are still some minuscule aliases with synthetic loud high frequency tones, but with any real sound there will be none. Yes, you can use 999 but there will be no big difference in the final quality. Anything above 600 gives the same quality for 16 bit data.

Keep the original AC3 file :)

The original audio stream I want to use for video backup on CD is LPCM (2Ch) 48 kHz 16 bit (uncompressed). Or are you talking about my 3rd question? If so why AC3 and not SDDS?

I would probably also keep the ac3 sound for the video. It is relatively easy to mux ac3 with divx into an avi or ogm container. I know you only need 2 channels but most if not all ac3 filters will downmix to 2 from 5.1.
I wouldn't bother with aac and the mp4 container atm as it's too much trouble.
One other option is to convert the audio you're intending for your audio cd to ogg vorbis for muxing into an ogm container. I don't know for sure but I assume the LPCM track is of higher quality than the ac3.
If you would rather vbr lame mp3 then you should also mux this into an ogm container as muxing vbr audio into an avi container breaks the specs and is generally not recommended.

btw, if it's not clear everything I've mentioned is in regards to muxing with divx (or xvid) video.

Thanks. I think it's a good idea to keep the ac3 sound and mux it with xvid. It's just ~ 450 kbps while nero AAC extreme, vorbis -q6 or lame -aps will be ~170-200 kbps (and I think better quality if I take the uncompressed LPCM stream as source for compressing).

About container: Ogm will be my choice, your comments helped me a lot. I tested some old divx-mp3VBR-avi DVD backups I made some time ago and there are indeed sync problems when jumping forward/backward. I don't want to find out how much trouble it is to create a mp4 container either.

About audio: either 48->44.1 khz -> mp3 lame -aps/e/i or vorbis -q6. Fortunately there's more than enough valuable information here on the board that will help me - and I'll do some tests (I moved some months ago and unpacking a box I've just found my Sennheisers ).

Update over the resampling issue:

If you are going to compress the resampled data, better also keep it at 32 ot 24 bit in order to avoid innecessary added dither, compressors don't usually require 16 bit data. Second best option is to use 0.9 bits of flat dither (no noise shaping) instead of the previously recommended dither with noise shaping.

Again thnx for your input! I'll use your "best" option for sure when I'll create mp3s for portable use.
For the ogm CD issue I'll use vorbis -q6 (+XviD for video - compressing right now). As I've found a directshow filter for monkey audio I'll find out if there's a way to mux lossless audio - probably a waste of time, seems like I have too much of it

For the time being it seems like matroska will be out earlier than MPC SV8 now, and according to Frank's recommendation there is no sense in muxing MPC SV7 streams into matroska, so development of this was stopped for the time being. Frank will provide us with SV8 sample files pretty quickly he promised, so hopefully you dont have to wait some more months ...



I second that statement.

Menno

Yuck...that K+K site has nothing informative and also has bullshit...
I'd say is most definately the best response.
How did you even come to the conclusion it should be the best??