HydrogenAudio

Lossy Audio Compression => MP3 => MP3 - Tech => Topic started by: Mark Modrall on 2006-11-18 17:10:42

Title: Lame/Audacity/OSX
Post by: Mark Modrall on 2006-11-18 17:10:42
Posted this on the Source Forge LAME forums, but those get very little traffic it appears.  The only reply in months to any post has been "try posting this on hydrogen audio".  So here are a few of the questions we had posted over there:

1) How does one compile LAME so that it can be used with Audacity?  The shared lib compile they had on the Audacity page was for something like Lame 3.90.  I've tried a few different switches on the lame compile but I've never found a combination that produced something Audacity would pick up.

2) On the dbpoweramp forums, they said that mp3 is much worse at bitrates < 96 compared to wma and audible; why would that be?  I rip a lot of audio books for use on ipods, etc, so that limits the formats I can use but I noticed Audible uses 32kbps mono and it's quite listenable while the same settings with Lame are really unintelligible.

3) I've noticed with Lame that ripping things mono vs stereo doesn't result in file size compression for the same bit rate; is that because lame going to fill the extra space with more information?

4) is there a good mp3 joiner for osx like mp3merge for windows?  As I said, I rip mostly audio books and would prefer grouping tracks into chapters rather than 2 minute chunks.  I often rip on osx and then copy the tracks to my wife's pc so that I can use mp3merge to do the joins

thanks
mark
Title: Lame/Audacity/OSX
Post by: kjoonlee on 2006-11-18 17:44:23
Hi, welcome to Hydrogenaudio.

1) You should get libmp3lame.so.* and/or libmp3lame.a if you compile it from scratch. I think libmp3lame.so points to the shared library.

2) It's old and unoptimized for that range, which explains the disadvantage against WMA. It's also general-purpose, unlike voice codecs which specialize in speech compression.

3) Bitrate is filesize divided by playtime, so if the playtime and the bitrate is the same, filesize will also be the same.

1) Well, that's how it works with Linux. I'm not sure what could go wrong if you run OS X.

3) If you choose mono instead of stereo, you can halve your bitrate to get roughly-the-same quality.
Title: Lame/Audacity/OSX
Post by: ffooky on 2006-11-18 19:12:22
1) If you're on an Intel Mac, this (http://spaghetticode.org/lame/libmp3lame.dylib.zip) allows you to use 3.97.

4) Nowt at the moment, though Fission (http://www.rogueamoeba.com/fission/) seems like it might feature joing in the future.
Title: Lame/Audacity/OSX
Post by: Mark Modrall on 2006-12-25 14:51:12
1) If you're on an Intel Mac, this (http://spaghetticode.org/lame/libmp3lame.dylib.zip) allows you to use 3.97.

4) Nowt at the moment, though Fission (http://www.rogueamoeba.com/fission/) seems like it might feature joing in the future.


Thanks, but I'm on a g4 iBook.  I did get a .dylib when I built LAME locally, but Audacity 1.2.6 doesn't recognize it.  Not sure how it has to be packaged.  The LAME download page from Audacity is still using 3.9.1 which is pretty old.

Mark
Title: Lame/Audacity/OSX
Post by: EternalEngine on 2012-04-06 03:05:57
Please, can somebody compile libmp3lame.dylib optimized for G4 CPU. I tried to compile it by myself, but it was too difficult for me. I need it for use in Audacity to record live audio stream, but the lame 3.97, that goes with Audacity is too slow, and i can't work in real time mode with it. =( So, I would be very grateful if someone could send me a mail with this! light_here@mail.ru