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Non-MP3 Codecs?
Vanth Dreadstar asks: "While
MP3 is okay, I have begun researching other codecs that would be
suitable for my home music use. Lossy codecs such as Ogg
Vorbis, AAC,
and MPC all seem to have promise, not to mention the lossless codecs
such as Shorten
(otherwise known as .SHN),
LPAC, and FLAC.
I would like to know what non-MP3 codecs people are using out there,
and why."
Another consideration is the straightforwardness of the API for the library you intend to use. Vorbis has a somewhat reasonble API with a liberal addition of quirks. Also you can easily add metadata to Vorbis files. Ever tried adding metadata to an MP3 file? ID3v1.1 is trivial but ID3v2 has a 95,000 line reference implementation. Uh? UH?
Any application has to support PCM audio also, since most music collections are primarily on CD.
I recently bought a Rio Volt MP3/WMA CD player, and compared WMA8 with VBR LAME, and LAME won hands down. Both encoders are set to come out around 128kbit, and while both of course have artifacts, the artifacts in WMA are MUCH more noticeable. I guess I'm just alot more sensitive to the type of artifacts WMA produces...
Sticking with MP3s is a no brainer unless you have to use open software for moral reasons, since Apple has enhanced MP3 encoding/decoding for AltiVec, and this is an area where those gigaFlops do wonders at quick, high-quality encodes and freeing up more CPU for your work (or the visualizer :) during playback.
"Reality is just a convenient measure of complexity" -Alvy Ray Smith
is a ftp database and crawler similar to audiogalaxy only for ogg. it would catch on in no time.
Bear in mind that the ~4x compression rate listed for lossless compression schemes is heavily reliant on the input. Don't be surprised if you get 1.5-2.5 compression a lot of the time, and remember that there's a good chance you'll get 1:1 (or worse) compression results with a 'random' enough song file.
Obliteracy: Words with explosions
JPEG users have available to them some command line utilities that permit simple alteration of images without loss of quality, for example, rotation and flipping. Are there any similar utilities available for any of the major audio compression formats?
The reason I ask is that I have ripped a number of CDs and the volume levels vary noticibly. I like to listen to MP3s as I work, with the volume turned down far enough that I can hear the music, but any one that I'm on the phone with won't. Unfortuately, there doesn't seem to be a single setting for everything that I've ripped. While I could go back and re-rip, I'd much rather have a toolbox of useful batch utilities. Ideally, it would allow me to write, say, a Perl script that generates a histogram, checks the average and peak volume, and then tweaks a single number in the file header to force it in line with the rest of my collection.
Is this sort of thing possible?
Nothing for 6-digit uids?
After collecting 60 Gb worth of mp3s, I switched to almost strictly shn format
over 2 years ago. Here is my reasoning:
1. Stick with a lossless format if you can afford the bandwidth and storage
space. Plan for the future, when bandwidth and hd space will be much
more plentiful.
2. I can definitely hear the difference between lossless and any compressed
format at 128 kb/s (that annoying wavery sound), and even at 256 kb/s (barely)
on very delicate passages and high-end speakers.
3. Also, if you want to reprocess the music (dehiss, dehum, equalize, normalize,
respatialize, etc) you experience a much more noticeable degradation in the
sound if you start with a lossy format.
4. shn is the standard format for trading music.
It is a lot less work to store in shn then have to decode and reencode every
time you make a music trade.
For lots of good links on shn format, see my trading page at
http://www.vsl.ist.ucf.edu/groups/vtb/TradeList
(Now that I've come this far, what the hell, trade requests here
.
;-)