Unoffical empeg BBS

Quick Links: Empeg FAQ | RioCar.Org | Hijack | BigDisk Builder | jEmplode | emphatic
Repairs: Repairs

Topic Options
#103599 - 08/07/2002 08:47 Fraunhofer vs. Lame
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
Yeah, I've read the r3mix site, but it's old information and I have a newer problem.

On the PowerMac at home, iTunes presumably has some variant of the Fraunhofer encoder built in. It appears Apple did a bunch of performance tuning because it's screaming fast and it uses both of my CPUs, yielding a net compression speed of something like 10x. Lame, on the other hand, is blindingly slow in comparison (running at 1.5x real-time per CPU). Plus, the hack to use lame in iTunes is neither smart enough to rip in advance nor smart enough to run multiple lame processes concurrently.

So, my question is whether anybody has the appropriate analysis tools (i.e., the frequency response graphs from the r3mix site) to compare the MP3 quality of the current Fraunhofer codec (as used to by Apple) to Lame.

Or, just in general, is the quality of 'lame --alt-preset standard" noticably better than the "best" VBR quality out of iTunes? If nobody out there knows the answer, then it looks like I'll have some experiments of my own to perform...

Top
#103600 - 08/07/2002 09:06 Re: Fraunhofer vs. Lame [Re: DWallach]
Terminator
old hand

Registered: 12/01/2000
Posts: 1079
Loc: Dallas, TX
I don't know the answer to your question, but it sounds reasonable that quality was sacrificed for speed. I'd strongly suggest doing your own tests, that way you will be able to hear the difference for yourself instead of looking at frequency graphs to determine the difference.

Top
#103601 - 08/07/2002 09:16 Re: Fraunhofer vs. Lame [Re: Terminator]
SE_Sport_Driver
carpal tunnel

Registered: 05/01/2001
Posts: 4903
Loc: Detroit, MI USA
ineedcolor commented that LAME sounded more "flat" where as Fraunhofer seemed to emphasize the bass a bit more. One isn't better than the other once you EQ to your tastes,but the haslte of having 1/2 of your collection compatible with your EQ settings and the other 1/2 not wasn't worth the time for him, so he just stuck w. Fraunhofer.
_________________________
Brad B.

Top
#103602 - 12/07/2002 08:42 Re: Fraunhofer vs. Lame [Re: DWallach]
lamer
journeyman

Registered: 30/01/2002
Posts: 87
Loc: Texas
I beleive Fraunhofer was optimized for low bit-rates (ie web radio, audio books, etc.) and is apparently very good at it. Lame is optimized for high bit rates (192kbs and above) and is also very good at it. For anyone who appreciates a quality digital recording and has enough disk space you should really consider using a high bit rate and a quality encoder despite the speed disadvantages. I ripped and encoded about 11Gigs of mp3s using Xing at 128 before I realized that speed wasn't everything. Some of the songs sounded like crap. I did a little research and some of my own comparisons and decided to just rip everything at 320kbs CBR stereo and by bigger hard drives. You may not need it all, but sure enough the one crappy encoded section will surface in your favorite song, at your favorite part and ruin all your hard work. Here's a link that might be of interest.
_________________________
MK2a 160GB

11 Years later, these Mk2a units still rock...

Top
#103603 - 12/07/2002 09:03 Re: Fraunhofer vs. Lame [Re: lamer]
SE_Sport_Driver
carpal tunnel

Registered: 05/01/2001
Posts: 4903
Loc: Detroit, MI USA
Nice link lamer.
_________________________
Brad B.

Top
#103604 - 12/07/2002 16:04 Re: Fraunhofer vs. Lame [Re: lamer]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
These things are nice to read, but the problem is that they're dated. Both the r3mix page and this one haven't changed, while the encoders have evolved a lot. To learn how lame has evolved, you just have to read their ChangeLog. No equivalent document seems to exist for Fraunhofer.

*sigh*

One of my projects for this weekend is going to be performing some A/B tests, encoding the same tracks with lame and Apple's Fraunhofer coder, burning out a CD, and then comparing both with the original data using good headphones.

Top
#103605 - 13/07/2002 17:24 Re: Fraunhofer vs. Lame [Re: DWallach]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
Okay, experiment over. I concluded that lame (v3.92, --alt-preset standard) and the Fraunhofer encoder (iTunes 2.0.4, VBR "highest" quality) are indistinguishable, both from each other and from the original WAV file.

My listening environment was a little unorthodox. I went into a quiet room with my laptop (HP Omnibook 550), my Onkyo SE-U55 USB external sound card, and Grado Labs SR-60 headphones. I converted the MP3 files back to WAV (using lame's decode option) and listened to everything using three instances of WinAmp, one with each set of WAV files. This let me flip back and forth rapidly between tracks and between different versions of the same track.

I tried to listen carefully for subtle details in the background (e.g., musicians talking off-mike), as well as common things like ringing issues on the attack or the effects of the low-pass filter. Honestly, I didn't hear any differences.

Now, iTunes has been optimized to use dual CPUs if you've got 'em. It runs for me between 13x and 20x realtime. Lame can only use one CPU and runs at 1.5x (although I'm sure some AltiVec performance tuning could help it a lot). In addition to the performance difference, there's also a bitrate difference. On one of my test tracks (Count Basie & Oscar Peterson playing "Louis B." from "Satch and Josh", the XRCD remastered version), lame averaged 189kbits/sec, while the Fraunhofer coder averaged 147kbits/sec. Similar numbers showed up elsewhere.

My conclusion: if you use a Mac with iTunes, there's no need to use lame. If you run the built-in Fraunhofer coder with VBR and the "highest" quality, what you get out is perfectly "CD quality" and you get it at a lower bitrate.

Top
#103606 - 16/07/2002 09:38 Re: Fraunhofer vs. Lame [Re: DWallach]
Mario
stranger

Registered: 04/03/2002
Posts: 42
Loc: Ireland
Hi,

I also use iTunes with LAME and I must say I haven't done any comparation. I use an G3 iBook 600 Mhz and LAME is very slow. Now that I read your tests I will probably use Fraunhofer. But there is something which you did not mentioned. What was the minimum bit rate you set in MP3 iTunes settings. Because if you say that you got 147 kb/s vs. I think 189 kb/s or so for LAME, you did set minimum bit rate at about 128 Kb/s, right? because otherwise if you set a minimum bit rate to 160 kb/s (what I think you should do), you can not get an average lower than that, right?

Another question, how do you import to MP3? do you import it direct from CD? or do you import first to WAV? How do you make backups, do you burn CD-RW? (that's what I do), I must say for me the biggest issue with MP3 ist to make backups

see you
Mario
_________________________
Thanks / Gracias Mario The Spanish guy living in Ireland Homepage: www.livemyadventure.com

Top
#103607 - 16/07/2002 09:49 Re: Fraunhofer vs. Lame [Re: DWallach]
mrfixit
enthusiast

Registered: 14/06/2002
Posts: 337
Hi, I have been using music match jukebox to encode my cd's, I encode them at 192cbr and they seem to sound pretty good. I have also used audiocatalyst with the same results. Both of these programs run pretty fast, about 1.25 min per song for the whole processes, but when I use a program that uses lame or fraunhofer it takes like 10 min per song, ummm... why?
_________________________
Ben
mk2a 60gig green/Greenlights Buttons
mk2a 60gig green/Greenlights Buttons
mk2a 40gig blue no illumination....yet
hijacked

Top
#103608 - 16/07/2002 13:28 Re: Fraunhofer vs. Lame [Re: Mario]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
What was the minimum bit rate you set in MP3 iTunes settings.

I had it set to 128kbits, which is the same as lame uses for --alt-preset standard.

Another question, how do you import to MP3? do you import it direct from CD? or do you import first to WAV? How do you make backups ...

My MP3 collection is a mish-mash of older files from older computers (imported, variously, with grip, audiograbber, and eac, but all compressed with lame), as well as new ones imported using iTunes. Right now, I'm just letting iTunes do its default thing, which is compressing as it imports. I'm not explicitly worrying about backups because I copy the music from my home computer to two empeg's (one in the car, one in the stereo rack). In a worst case failure, I can just recover the files from an empeg.

when I use a program that uses lame or fraunhofer it takes like 10 min per song, ummm... why?

This depends on far too many things. For starters, there's a speed vs. quality tradeoff. If you run lame in CBR mode, it's much faster than VBR mode. Likewise, newer versions of lame are significantly faster than older versions. Ultimately, if you're using a program like EAC or grip, then it doesn't really matter. Lame runs in the background, but your rips run at full speed. So long as you've got enough disk space to hold the temporary raw CD data, you don't really care how slow your CPU is.

Top
#103609 - 18/07/2002 10:51 Re: Fraunhofer vs. Lame and new iTunes 3 [Re: DWallach]
Mario
stranger

Registered: 04/03/2002
Posts: 42
Loc: Ireland
Today I dowloaded the new version of iTunes, iTunes 3 with a lot of nice features and found it work very well in my iBook.
Have you tried it yet?
Itunes always wants to sabe the mp3 files using only the song name. I know that you can rename the files again with Applescript plugins or extra programs (I use the plugins). Do you rename them to you know, Artist - CD title - Track -song, to export them to the Empeg? I want to delete all the files of the empeg and copy again from iTunes to Empeg, since I made a lot of fine tuning with the names and I'm a bit confused with how important are for the empeg the file names.

By the way for backups, what I do, I use CD-RW and I copy all files to the CDs on Alphabetical order, I have a CD-RW for A, another one for artist beginning with B an so on. When one gets full, I just copy all that to a CD-R (or leave it as CD-RW it dependes how lazy I feel that day)


thanks
Mario
_________________________
Thanks / Gracias Mario The Spanish guy living in Ireland Homepage: www.livemyadventure.com

Top
#103610 - 18/07/2002 15:05 Re: Fraunhofer vs. Lame and new iTunes 3 [Re: Mario]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
I was playing with iTunes 3.0 last night. It's pretty cool. It would be nice if some future version of the empeg software would recognize the ID3 volume adjustment tags that iTunes now writes out.

About renaming files to something more reasonable: you've got an AppleScript for this? Where do I get it?

Top
#103611 - 18/07/2002 16:27 Re: Fraunhofer vs. Lame and new iTunes 3 [Re: DWallach]
Terminator
old hand

Registered: 12/01/2000
Posts: 1079
Loc: Dallas, TX
I thought there was a volume gain parameter on every mp3, and I thought that most decoders already use it. Theres even a windows utility that takes advantage of this and tries to normalize across your whole collection (If you want it to).

Top
#103612 - 18/07/2002 16:45 Re: Fraunhofer vs. Lame and new iTunes 3 [Re: Terminator]
tfabris
carpal tunnel

Registered: 20/12/1999
Posts: 31583
Loc: Seattle, WA
I thought there was a volume gain parameter on every mp3, and I thought that most decoders already use it.

Each and every FRAME of an MP3 has a gain parameter, it's part of the internal audio decoding data-- you have a given group of audio bits scaled a certain way, so the gain parameter is the scaling factor for that frame. It's just part of the encoded data stream.

Now, you CAN globally adjust this parameter across an entire file. But if you increase it, on most MP3 files, you will cause the audio waveform to clip because most CDs (and the MP3s made off of them) are already normalized, as discussed here.

Now, you could theoretically decrease this value globally across your entire MP3 collection, making your loud songs quieter. But then you run the risk of hitting the "floor" value for this parameter (I think...) on some frames. Meaning you'd get no audio for extremely quiet parts of songs.

Even if it did work, you'd be making your MP3 collection quieter (collectively on average), meaning that if you just ripped the new Sheryl Crow CD and played it without decreasing it first, you'd probably blow your speakers (man that album is LOUD).
_________________________
Tony Fabris

Top
#103613 - 19/07/2002 10:51 Re: Fraunhofer vs. Lame and new iTunes 3 [Re: Terminator]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
What iTunes is doing is that they've added an ID3 tag that includes a volume adjustment. iTunes will happily scan every MP3 file on your disk, and for those that haven't been normalized or whatever, it writes a volume adjustment hint into the ID3 tag. Then, when you're playing the song (either with iTunes or an iPod), it automatically turns up the master volume. Needless to say, this is pretty cool.

Top
#103614 - 19/07/2002 11:36 Re: Fraunhofer vs. Lame and new iTunes 3 [Re: DWallach]
rob
carpal tunnel

Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
Apple took the credit for ID3V2 EQU2 and RVA2 did they?

Rob

Top
#103615 - 19/07/2002 18:04 Re: Fraunhofer vs. Lame and new iTunes 3 [Re: rob]
DWallach
carpal tunnel

Registered: 30/04/2000
Posts: 3810
I wouldn't say they're taking credit for it. But they're supporting it in a nifty way.

Top