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Fr4nz
Christian mpc.corecodec.org doesn't work...
user
well, Frank K. is The man.


my thoughts:

these days space isn't such an issue any more, even not for video.
You can compress mpeg2 video a little bit more, and fit a lot on DVD+-R/Video.

As audio stream you can use the original ac3, if your purpose is an backup.

But:
ac3 isn't that perfect, dts would be.

So, what we need since some loner time:

multichannel "mpc", as SV7, 7.5 or 8,
the end-user won't care as long as it runs smooth.

For self-made video maaybe HQ stereo is needed, too,
so matroska with mpc is needed !

Of course, the end-users won't care much about the name, mpc, ac3, or aac.

So, in fact, it would be fine, if Frank K. (together with others) could either make an improved AAC (or ac3 if possible, but imo, ac3 has a very weak sound, so I dunno, if good sound is possible at all with ac3).

A final mpc SV7, 7.5 or SV8 would be nice, too.
I think, the psy-model does not need more tweaking at this time.
You would have to invest really a lot time for tweaking and testing, abxing,
but results, improvements would be minor at this stage, MPC has already reached (see the 128k test at the bottom line...)

So, the work should concentrate on that, what Citay told, including --xlevel eg.
And the possibility to include this stereo mpc into video container.
Maybe this 2 topics should be differentiated.
As it seems, that including SV7 into video properly is a little bit difficult, it might be the good idea to make SV7 final, like others proposed here.
And simply make a proper SV8 stream definition, for video, maybe multichannle, too ?, using the excellent psy-model of current SV7.

well, imo, a bitratesaving multichannel codec needs a lot tweaking to the perfection, mpc stereo has currently.
But imo, the optimizing for multichannle can be done later, if the "container" SV8 would work in general.



well, as Christian told, Frank K. has already sent a detailed ToDo List, nobody knows better, what to do, than him !

smile.gif
rjamorim
QUOTE(user @ Nov 21 2003, 06:30 PM)
But:
ac3 isn't that perfect, dts would be.

huh.gif

DTS is closed, proprietary and CBR. It also barely uses psychoacoustics, the processing is almost only quantization. It's only supported on DVD players and receivers, and you won't find specifications nor reference sources anywhere. It's as bad a choice as it can be.
Jebus
QUOTE(2Bdecided @ Nov 21 2003, 01:48 AM)
Now, be careful here. As clever as Frank is, some of these posts almost sound like they're suggesting that Frank is God, and current AAC encoder developers are stupid!

The idea that Frank can port is psy model to AAC, and magically it'll be perfect sounds a little strange. I'm sure the friendly AAC encoder developer we know is already doing a good job. wink.gif


I agree it would be cool for Frank to get (re)involved with any audio coding project - I was just a little worried that some of the comments in this thread might offend the people who are already working on a certain codec. Though they've probably got better things to do than be offended by such gentle comments.

Cheers,
David.

Sorry, I meant an AAC encoder focussed on transparency would be nice. The ones out there right now, while having extremely capable developers working on them, tend to be focussing on the lower bitrates. I would assume any work Frank would be involved with would lean more towards what we around here are interested in.
ssjkakaroto
IMHO if Frank (or any other dev) could fix the problems MPC has with some problematic samples on -q 5+ it would be more than enough for now and maybe in the future (near?) him and other devs could work on low bitrate tweaking, multichannel, implementing SV8, the AAC decoder idea, etc.
SacRat
Well, no matter, wht project Frank would be in, but let's all wish him luck.
We have at least MPC. With all its limitations, advantages and so on...
If Frank would decide to make an AC3 codec or another free AAC encoder, I'm sure, he'll make a good job.
Guys, let's stop moaning about "MPC's death". Those of you, who don't like it still have a whole damned lot of other formats.
Whatever Frank decides, it's his decision and we MUST respect it.
BetaBoy
QUOTE(Fr4nz @ Nov 21 2003, 06:43 PM)
Christian mpc.corecodec.org doesn't work...

Were working on CoreCodec.org ATM it will be back up soon. If not already ;-)
AgentMil
So far MusePack is the closest a lossy codec has come to being "transparent" IMHO... so although it looks like its "dead" this is format for "transparent" lossy encoding. (Although at the rate AAC is going we might have to look at that soon laugh.gif ).

Regards

AgentMil
plonk420
QUOTE(rjamorim @ Nov 21 2003, 02:33 PM)
QUOTE(user @ Nov 21 2003, 06:30 PM)
But:
ac3 isn't that perfect, dts would be.

huh.gif

DTS is closed, proprietary and CBR. It also barely uses psychoacoustics, the processing is almost only quantization. It's only supported on DVD players and receivers, and you won't find specifications nor reference sources anywhere. It's as bad a choice as it can be.

well, DTS is the best you get in theaterland. AC3 is an earsore. however, i didn't see the point in bringing it home once it GOT home, seeing as how AC3 had a sufficiently high enough bitrate not to sound fugly on DVD. but this is extremely OT.
Eli
QUOTE(2Bdecided @ Nov 21 2003, 04:48 AM)
Now, be careful here. As clever as Frank is, some of these posts almost sound like they're suggesting that Frank is God, and current AAC encoder developers are stupid!

I am sorry if anyone has misinterperrated what I have said or been offended. There are clearly very talented ppl currently working on AAC, but their focus seems to be on low bit rate encoding, something I could care less about. Frank is concerned almost solely with transparency - the thing IM most concerned about. So if Frank can bring his knowledge, expertiece, and approach to AAC that would be amazing. He also hinted that he could greatly reduce the CPU load for decoding AAC files similiar to MPC. The origninal post sounded like Frank thought he could do everything he has done for MPC with AAC, so basically you would get MPC with wide industry support! Thats PERFECT for my needs.
BadHorsie
I'm not an codec expert,

but i like the idea to develop a psy model witch can be used by nearly every codec. I would also like to have a free ac3 and or dts encoder. A free aac encoder which can be used on every platform would be great too.

But if i think twice, i would say "let's make a new mp3 encoder!". With Frank's psy model acknowledgement it should be possible to build a new mp3 encoder which works only in vbr and can reach true transparency, including overtones and a even frequency response from 20 Hz to 20 kHz.

Call me ignorant, but for me as musican the existing codecs dosn't satisfy my needs. I use FLAC to archive my own recordings and MP3 or Vorbis to distribute preview songs. But for listening music on a walkman or in living room i switched back to good old audio cds. One codec sounds good but playback is only possible on a computer. The other codec is present at nearly every device like dvd players, computers, cellphones, walkmans etc. but can never reach transparency and sounds only good if you compile them with the intel compiler from 1998 on a WindowsNT 4.0 with xyz compiler flags in a full moon night.

There are so many people with codec skills which have spend hundreds of hours to different audio formats. Would it be possible to merge the whole horsepower into one project, people would have the best audio codec, available for every platform and every device.

Just my four cents
BadHorsie
CiTay
QUOTE(BadHorsie @ Nov 23 2003, 05:45 PM)
But if i think twice, i would say "let's make a new mp3 encoder!".

Well, as you can see here, Frank Klemm was once a developer in the LAME team. He wanted to do some pretty radical code overhaul, which lead to discrepancies within the dev group (mainly Mark and Naoki) and eventually to him quitting and later starting to work on MPC.
rjamorim
I think MP3 is too limited (sfb21, fixed bitrates, no multichannel, no 24bits depth, no frequencies higher than 48kHz, bitrates limited to 320kbps...) to use Frank's psychoacoustic model's full power.

Adapting one of the several analogies that were in vogue here at HA some time ago, it's like putting a Boeing engine in a VW Beetle :B
Gabriel
QUOTE
I think MP3 is too limited (sfb21, fixed bitrates, no multichannel, no 24bits depth, no frequencies higher than 48kHz, bitrates limited to 320kbps...) to use Frank's psychoacoustic model's full power.

I agree, except on this part:
QUOTE
no 24bits depth
ChristianHJW
I was posting some answers back to Frank about his last proposal to make a SV7 to SV8 conversion tool, the email is mirrored here

For your convenience i copy and paste the content here also :

Christian HJ Wiesner wrote:

QUOTE
Frank Klemm wrote : First goal of "transpacked SV7" SV8 is to make the blocks independent from others.
SV7 uses differential encoding acrossing block boundaries.
This (the removal of this cross block differential coding) need some additional bitrate,
but it makes software design much more simple and makes it easier to write
addtional tools.


Forgive me if i am talking complete rubbish, but i have more and more
problems understanding what you are trying to do here :

From my understanding the SV8 framing should not only bring a new
framing, but also introduce serious changes to the blocks itself ? If
you make an app that simply 're-packs' SV7 files into a SV8 framing,
will the old blocks be converted also, so they are SV8 compliant, or do
you plan to introduce a 'SV7 compatibility mode' in SV8, so that SV7
blocks can be put into the new framing ?

For the changes to the blocks itself, i do understand that the follwoing
new features require a new block design :

- multichannel ( 5.1 )
- more flexible sampling rate support
- DRC
etc.

Now with respect to what you told me on the phone, i mean your ideas
about leaving the subband encoder design completely for next musepack,
how about considering tow steps for this :

1. SV8 : subband encoder like SV7, but adding all the new features
listed above

2. SV9 / new codec name : new encoder based on tranformation encoding,
or a new OSS AAC encoder

Christian

QUOTE
First we should discuss about the size of these independent blocks.
AC3 calls this blocks audioblocks.

* Basic block size of SV7 is 1152 samples. I would use a multiple of this for "transpacked SV7" SV8. Examples:

        a) 2 blocks  => 2304 samples ( 52 ms for 44.1 kHz,  48 ms for 48 kHz)
        b) 4 blocks  => 4608 samples (104 ms for 44.1 kHz,  96 ms for 48 kHz)
        c) 8 blocks  => 9216 samples (209 ms for 44.1 kHz, 192 ms for 48 kHz)

        Samples should be stored in a way so it is possible to decode block by
        block to minimize memory consumption, even when this is not done in the
        reference implementation.

* Native SV8 for 32 kHz...64 kHz sample frequency.
        a) 4096 samples ( 93 ms for 44.1 kHz,  85 for 48 kHz)
        b) 8192 samples (186 ms for 44.1 kHz, 171 for 48 kHz)

For 8...16 kHz this is quartered, for 16...32 kHz it is halved, for 64...128 kHz doubled
and for 128...256 kHz four times larger. But this only as remark.
Frank Klemm
seanyseansean
Exactly what bitrate increase are we on about Christian? Anything major essentially reduced the efficiency of musepack compared to other codecs. I understand why it needs to be done because of the matroska container format, but isn't there another way? As far as I can see you're taking the top and bottom of each frame and adding it to the surrounding frames, that's surely a bit wasteful?

Whatever - i'll still look forward to it. Nice to see you still have a dialogue with Frank.

sean
BadHorsie
Ok,

MP3 is a very old format and restricted in many ways. But it is the only format with true hardware support, isn't it? It is the only format witch works on every platform too.

As for AAC, i would understand the hype if i where on a Windows or Apple box. But as a Linux only user AAC is nothing than a buzzword for me.

It seems that i have to pay EUR 3000,- for a Apple Powerbook and EUR 600,- for a IPod if i want to listen music in the future, or just stay with AudioCD/Cassette combination.

I believe that SV8/9 could get a really nice audio codec but we have to wait a long time to play those files on any hardware outside a computer, if ever.

It seems to me that every development since CD_DA was a step backward, really.

BadHorsie

BTW: There are many Live DVDs wich come mastered with a 5.1 AC3 track @ 384 kbs which sounds not bad. So the 320 kbs limitation in MP3 should not be a really problem for two channel tracks if the encoder would be carefully tuned. And 16 kHz limitaion should not be a big problem too. Most midrange CD Players have a frequency response limited from 30 Hz to 16 kHz and can sound really good if bundled with good cable/speaker combination. But as i said before, i'm not an codec expert.
KikeG
QUOTE(BadHorsie @ Nov 24 2003, 02:30 PM)
BTW: There are many Live DVDs wich come mastered with a 5.1 AC3 track @ 384 kbs which sounds not bad. So the 320 kbs limitation in MP3 should not be a really problem for two channel tracks if the encoder would be carefully tuned.

Are you saying that current recommended LAME encoder doesn't sound transparent on most things at 320 Kbps? I bet it's more thansparent than 5.1 channel 384 Kbps AC3. If you mean that, then I'd say you are being victim of placebo effect. Try some ABX tests with the recommended --aps, --ape and --api LAME presets, and check for yourself how severe are transparency problems.

QUOTE
And 16 kHz limitaion should not be a big problem too.


If I'm not wrong, it's a limitation on encoding efficiency, nothing else. LAME alt-presets lowpass quite over this 16 KHz frequency. Very little real-world music is affected audibly from these lowpasses.

QUOTE
Most midrange CD Players have a frequency response limited from 30 Hz to 16 kHz and can sound really good if bundled with good cable/speaker combination. But as i said before, i'm not an codec expert.


In this context, the cable would be the least important of your concerns.

Edit: sorry if I'm taking some things out of context.
David Nordin
I would be interested in seing Musepack's benefits into AAC smile.gif or AC3.
DAvenger
Christian, do you think it is possible to obtain the SV7 encoder sourcecode? I've sent a couple of emails to Frank but got no reply (I think I don't have his most recent email addy) ... if he would insist on keeping the source closed/non public (for any reason) I would of course respect that and keep all the work private.

Thanks
BadHorsie
QUOTE
Are you saying that current recommended LAME encoder doesn't sound transparent on most things at 320 Kbps? I bet it's more thansparent than 5.1 channel 384 Kbps AC3. If you mean that, then I'd say you are being victim of placebo effect. Try some ABX tests with the recommended --aps, --ape and --api LAME presets, and check for yourself how severe are transparency problems.


A sinful compression for walkman usage would be 160 kbs - 224 kbs average. A complete album in 320 kbs makes no sense. I just want to say that 320 kbs frames should be enough in a VBR situation to handle critical samples.

I did a lot of ABX tests with the --alt-presets (especially --alt-preset standard vs. --alt-preset fast standard with LAME 3.90.3 and 3.92).

QUOTE
If I'm not wrong, it's a limitation on encoding efficiency, nothing else. LAME alt-presets lowpass quite over this 16 KHz frequency. Very little real-world music is affected audibly from these lowpasses.


This is what i want to say. Even if the --alt-presets would lowpass at 16 kHz it would enough in most situations.

BadHorsie
user
QUOTE(rjamorim @ Nov 21 2003, 10:33 PM)
QUOTE(user @ Nov 21 2003, 06:30 PM)
But:
ac3 isn't that perfect, dts would be.

huh.gif

DTS is closed, proprietary and CBR. It also barely uses psychoacoustics, the processing is almost only quantization. It's only supported on DVD players and receivers, and you won't find specifications nor reference sources anywhere. It's as bad a choice as it can be.

"ac3 isn't that perfect, dts would be."

I meant this simply by comparing the resulting listening quality.
ac3 5.1 capped at 448 kbit/s, sometimes only 5.1 in 384 kbit/s.

Of course, dts uses way higher bitrates.
deej_1977
QUOTE(DAvenger @ Nov 24 2003, 05:07 PM)
Christian, do you think it is possible to obtain the SV7 encoder sourcecode? I've sent a couple of emails to Frank but got no reply (I think I don't have his most recent email addy) ... if he would insist on keeping the source closed/non public (for any reason) I would of course respect that and keep all the work private.

Thanks

Actually Dibrom got it with the help of Case.... So maybe you should talk to them.
Dibrom
QUOTE(deej_1977 @ Nov 24 2003, 11:19 AM)
QUOTE(DAvenger @ Nov 24 2003, 05:07 PM)
Christian, do you think it is possible to obtain the SV7 encoder sourcecode? I've sent a couple of emails to Frank but got no reply (I think I don't have his most recent email addy) ... if he would insist on keeping the source closed/non public (for any reason) I would of course respect that and keep all the work private.

Thanks

Actually Dibrom got it with the help of Case.... So maybe you should talk to them.

Just for clarification, especially on Case's part, Case did provide the sources to me but only because Frank had given him explicit permission to do so beforehand.

I think it's necessary to at least try and get a response from Frank first before the sources are distributed to someone.
DAvenger
QUOTE
I think it's necessary to at least try and get a response from Frank first before the sources are distributed to someone.


Sure. I'll try to PM Case and ask if he could get me the permission (or at least Frank's email).

Thanks
p0wder
QUOTE(MTRH @ Nov 24 2003, 06:52 AM)
I would be interested in seing Musepack's benefits into AAC smile.gif or AC3.

I agree 100%.
danchr
QUOTE(BadHorsie @ Nov 24 2003, 02:30 PM)
As for AAC, i would understand the hype if i where on a Windows or Apple box. But as a Linux only user AAC is nothing than a buzzword for me.

On a Linux box, you have the choice between LAME, Ogg Vorbis and FAAC - they seem to be the only decent open source encoders. MPC binaries are available too. I don't quite understand what all the fuss is about? You have access to three decent encoders, and if you own an x86 box, you can even run the remaining through WINE.
adlai
You know, reading it, I got the impression that Mr. Frank Klemm was a sort of guru who's insights were coveted by many but understood by few smile.gif

Interesting person, if I were in charge of a tech company I think I'd hire him!
ChristianHJW
QUOTE(DAvenger @ Nov 24 2003, 03:07 PM)
Christian, do you think it is possible to obtain the SV7 encoder sourcecode? I've sent a couple of emails to Frank but got no reply (I think I don't have his most recent email addy) ... if he would insist on keeping the source closed/non public (for any reason) I would of course respect that and keep all the work private.

Thanks

Martin, if you think about making an MPC encoder filter, please wait for SV 7.5. Frank made clear to me that SV7 files are DEFINITELY no good for muxing, be it via DirectShow or anything else.

I am bugging Frank on a daily basis now to make a SV7 to SV 7.5 trancoding tool, doing nothing else but to repack SV7 files such that the audio blocks are independant from each other. We havent decided yet if SV 7.5 is going to get released with an encoder of its own, as Frank's plan is to make no new framing for SV 7.5 ( so its actually nonsense to call it 'SV' .. lol ), his idea was to simply output blocks from the transcoding tool, ideal for being muxed into other containers smile.gif .....

After updating the decoder lib, it should be possible to play those fine on DirectShow, and from ANY container format supporting VBR and variable block length. I hope you guys will then update your DShow filter accordingly, we should talk before about what MEDIATYPE or MEDIASUBTYPE should be used for SV 7.5 then.

BTW : the SV8 alpha encoder is opensource and available from Frank's page, but unfortunately files created with it will not be compatible with any SV version existing, so its no big use right now sad.gif .....
Fr4nz
Is there any news?
rjamorim
QUOTE(user @ Nov 24 2003, 05:08 PM)
I meant this simply by comparing the resulting listening quality.
ac3 5.1 capped at 448 kbit/s, sometimes only 5.1 in 384 kbit/s.

AC3 5.1 is capped at 640kbps. Dolby Digital for DVD 5.1 is capped at 448kbps.

QUOTE
Of course, dts uses way higher bitrates.


Great, another good point against DTS tongue.gif
Fr4nz
QUOTE(rjamorim @ Dec 6 2003, 04:50 PM)
QUOTE(user @ Nov 24 2003, 05:08 PM)
I meant this simply by comparing the resulting listening quality.
ac3 5.1 capped at 448 kbit/s, sometimes only 5.1 in 384 kbit/s.

AC3 5.1 is capped at 640kbps. Dolby Digital for DVD 5.1 is capped at 448kbps.

QUOTE
Of course, dts uses way higher bitrates.


Great, another good point against DTS tongue.gif

Roberto do you know if the DVD's AC3 is re-encoded from the one @640kbps or is it encoded from a PCM 6-channel track?
rjamorim
QUOTE(Fr4nz @ Dec 7 2003, 07:37 AM)
Roberto do you know if the DVD's AC3 is re-encoded from the one @640kbps or is it encoded from a PCM 6-channel track?

I have no idea. But the AC3 hardware encoder (which, I guess, is used for encoding at studios) only accepts PCM imput. If they were to recompress the 640kbps stream they would have to first decode it anyway.
rjamorim
Some piece of history for you boys:

http://pub41.ezboard.com/fr3mixfrm6.showMe...opicID=32.topic

QUOTE
Author: buschel (---.ewetel.net)
Date: 12-24-00 02:34

hi !!!

as moose wrote i am working on sv8, which will allow streaming and i am also trying to speed up the fileseek...


SV8 has been on the works since late 2000...
Fr4nz
LOL
mdmuir
QUOTE(rjamorim @ Dec 9 2003, 05:01 PM)

Hello Roberto,

That "piece of history" link I take it is your sardonic sense of humor at work?

References to outmoded lame command lines (and the man it was named after) and similar musings and concerns three years ago about mpc (they were calling it mp+ in the thread)

Ouch and double ouch!
rjamorim
QUOTE(mdmuir @ Dec 9 2003, 08:16 PM)
That "piece of history" link I take it is your sardonic sense of humor at work?

Well, I sincerely dunno what you want to imply with it. I just meant that SV8 has been on the works for 3 years already.

In case you haven't noticed yet, I've been searching for old pieces of software for ReallyRareWares. One of the searches led me to that thread.

BTW: No, when I'm humourous, I generally use smilies.
n68
ciao..

well.. that was a good one..

according to that posting..

so to be more accurate.. the mp+ have been worked on.. in that period.
what about mpc.. after the "name change"..


wink.gif
user
well, that post of r3mix proves him wrong again !
Still mpc (not mp+++ lol) needs only minor cpu power for en or de coding.

And as we saw, mpc was developed to best lossy codec regarding psy-model, quality of sound, at least for stereo.

So what, we have mpc 1.14, and it is just great, and, after 3 years r3mix' pessimistic post, mpc is greater than ever !
Fr4nz
Now we should return IN-topic guys!

Are there any news about MPC SV 7.5 || 8 development?
ChristianHJW
QUOTE(Fr4nz @ Dec 11 2003, 10:52 AM)
Are there any news about MPC SV 7.5 || 8 development?

I just sent an email to Frank now to hear where we are standing .... will get back to you here if i have any news to report ....
Eli
Look forward to more news, IMHO if he can really apply the benefits of mpc to aac that would be the way to go. AAC already has hardware support and will probably be the next big codec. I would Frank be able to dedicate some time to this if the community could convince Nero (or doubtfully apple) to hire him for a bit or part time (basically, would money make a difference)?
Fr4nz
Why not working in the FAAC project? He could give it a boost!
mpcfiend
QUOTE
A more likely scenario is that the author will one day have other priorities than mp+ and development will stop because he's spend all the time he wanted to spend.


Well, he WAS right about that... dry.gif
Pike84
We'll just have to see about that.
westgroveg
It seems pretty clear to me that Frank has lost his passion for developing Musepack. I would look elsewhere for futher development. It would have been nice if he could have got someone else to continue the project, that's whats good about team projects like lame.
Rasi
any progress to that new official website?

it still says coming soon... only :/
ChristianHJW
This here will be the official website, until we can register musepack.org :

http://mpc.corecodec.org/
S_O
QUOTE
He sees AC3 as a very good
standard for his needs, because of well existing hardware decoders in
external receivers, a proper and well done specification and
implementation, and because with DVD burners beoming more and more
popular, low bitrates for audio compression will be only interesting for
streaming in future, and he doesnt see the big market for streaming at
all. He told me he is maybe interested in making a proper AC3 encoder,
using his own psy model, that in principal can be transferred from one
encoder to another.
A high quality AC3 encoder with advanced psychoacustics would be great, I think the format is quite good, if you look at the mp2 specifications, the format is quite simple, even I understood the bitstream. While looking at ATSC A/52 I gave up to understand it, this format is far more complex and not as limited as mp2. Hardware decoders are already excisting for this format, but I think low-bitrate is still very interesting, not only in streaming, but in portables. If you want a very small portable without a harddisk and you want to have 50 hours music on it, you have to use low-bitrate. Also the storage possiblities are getting and bigger, the device will get smaller, so low-bitrate is still needed. I donīt think AC3 can beat AAC+SBR or MP3+SBR (maybe not even WMA) at ~64kbps, even with a perfect psy-model.

What are the alternatives? We have 3 other formats with hardware decoders (portable support) more or less yet: AAC (some devices), Vorbis (very few devices) and ...... WMA (quite many devices)
WMA, this crappy thing is supported by many portables and DVD Players already, and there is a open-source decoder for it. While reading the comments in the source it seems that M$ has stolen ideas of AAC and Vorbis and pulled them toghether in one format, there are comments like:
/* NOTE: We use the same code as Vorbis here */
/* decode exponents coded with LSP coefficients (same idea as Vorbis) */
/* NOTE: this offset is the same as MPEG4 AAC ! */
It seems to be a MDCT format with PNS. The question is, is it possible to write a good encoder being compatible with the M$-Decoders, are there bitrate limitations etc. Is the entire format crap or only the M$-implementation? If the format is good this could be a alternative to AC3.

Also AAC and Vorbis are interesting, I think Vorbis can be tuned much more, you could get much more out of it at all bitrates (yust remember Garfīs Floggy-Vorbis demonstration with 5kbps-stereo-Vorbis), and instead of creating a new MDCT-format (MusePack SV8/SV9), why doesnīt he improve Vorbis? It is most likely the most unrestricted format at all. Another new format need much time to get accepted by users and even more time for hardware support.
If he donīt like Xiph he can write a completly new encoder. (Wasnīt there a rumor once Frank is working on Vorbis??) If Vorbis wonīt get improved with a higher quality encoder, faster decoder (is there still room to tune Tremor?), better compatibility with Windows (a new Ogg DirectShow Parser), it will be dying like VQF did and be overrun by WMA from the one and AAC from the other side.

I think Xiph did the wrong thing by starting Theora. This codec wonīt be much better than On2 VP3 and wonīt be able to compete with XviD, RV9, WMV9 or On2 VP6. They should have been concentrated on Vorbis to 80% and 20% to Tarkin. When time has come that H.264 can be used by the masses they had probably a good competor, Tarkin. And Vorbis now could beat AAC easily. Now they have two not-yet-finished (one not even really strated and one out-of time) Video-codecs, a Audio-codec with stopped developement it seems. Also Speex/FLAC should have been intigrated much faster in the entire project.

To come back to topic, a new MusePack wonīt succeed in my opinion, no matter how good the quality is, and if he focus on several things like a AC3 encoder which slows down the developement of other the project the new format wonīt succeed at all.
Ivan Dimkovic
QUOTE
While looking at ATSC A/52 I gave up to understand it, this format is far more complex and not as limited as mp2


Well, it is not that unlimited - bit allocation must be stored in the bitstream, and there is no easy way of replacing the psymodel since spreading is hardcoded with so-called "attack/decay" (fastgain/slowgain) strategies.

MP2 was unfortunately limited by early decisions in the MPEG commitee - MPC is a good example how MP2 would behave if frequency-band-wise M/S coding and huffman coding were applied to MP2.

QUOTE
And Vorbis now could beat AAC easily


I think this is quite an optimistic view on it - technically, Vorbis only contains a subset of coding tools available in AAC - properly tuned, MPEG-4 AAC encoder should beat Vorbis easily (as shown at 128 kb/s tests) - at low bit rate range I must admit that for LC version of AAC nobody from the main developers was interested in lossy stereo - so at 64 kb/s test LC AAC was beaten by Vorbis because Vorbis used lossy stereo. Anyway, with HE-AAC and new algorithmic additions which are to be added in 2004, it is a very powerful coding system actually not that easy to beat.
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