[BMT Micro: Your Source for OS/2 Software.]

MP3 Authoring in OS/2- by Lief Clennon

After my review a few months ago of WarpAMP, OS/2's own mp3 player, I was deluged with emails requesting information on how one can create mp3s. It is a simple (although tediously long) process. You need four things: a CD-ROM capable of digital transfer, a utility to do the actual transfers, an mp3 encoder, and a lot of patience. The utilities I mention in this article can be obtained from the links at the bottom of the page.

Digital transfer means that instead of the CD-ROM sending the audio data through the little two-wire cable to the sound card, it sends the pure digital data on the CD through the IDE or SCSI cable. This results in zero quality loss because the data doesn't go through any line-out processing. Most recent CD-ROMs have this feature; 1x through 4x probably won't work, 6x or 8x is a toss-up, 10x or better is nearly guaranteed to be OK.

The best OS/2-native CD ripper (as CD-ROM digital transfer utilities are called), is Alfons. It's missing a few features of DOS/Windows rippers; most notable are batch operations and sector synch, the latter of which helps to reduce errors when reading the CD (which show up as clicks or scratchy sounds in the output file), but for the most part these errors aren't too common.

The only mp3 encoder available for OS/2 is l3enc. It's actually got more features than most DOS or Windows encoders, although it tends to be slower, partly because it uses higher-quality encoding schemes and partly because it uses older methods. l3enc exists for several platforms; the OS/2 version is actually only version 1.0, but it's not missing much in the way of functionality, and the only bug I've found is that WAV file input doesn't work. (Because Alfons can output PCM files, this isn't a problem) Additionally, l3enc requires registration on other platforms, but the OS/2 version comes with the registration code.

Alfons and l3enc are both command-line utilities, so the first step is to open an OS/2 prompt. l3enc requires its registration file (l3encregister.inf) to be in the current directory when it is run, or it will ask you to enter the registration code. For those who like to muck about with background processes, I've discovered that if you "start /c l3enc" it will ask for the registration (just type what's in the l3incregister.inf file), and from then on any session of the program begun with start (but not detach) will not need the code. (It must be storing the code somewhere, but I can't find it. Sort of a Bermuda triangle effect.)

Create a directory to do your work in, and move there. You'll need about 12M of work space for every minute of the song(s) you want to encode: 11M for the raw data, and 1M for the resulting mp3 file. For each track you want to encode, give the command "alfons x: p g #" where x: is the drive letter of your CD-ROM and # is the track number on the CD. The p means to use a PCM output file rather than WAV, which is required for l3enc. The g simply means "get" the track number given as the next argument.

Once you have the track you wish to encode transferred to your hard drive, use "l3enc infile.PCM outfile.mp3" to do the encoding. infile.PCM is the Track#.PCM file that Alfons outputs, while outfile.mp3 is whatever filename you wish to give your mp3. This will cause l3enc to use certain defaults (128kbps encoding rate, stereo, 16bit, 44kHz), all of which are desirable in this case. Should you wish to use different settings, documentation is given in the manual.txt file that comes with the utility.

The actual encoding is the longest part of the process, but once it's done the work is pretty much complete. Delete the PCM files, move the mp3s to wherever you prefer to keep them, and you're done.

* * *


by Fraunhofer-Gesellschaft IIS-A
download from the OS/2 Supersite (ZIP, 72k)
Registration: Freeware


by Mikael Kjellström
download from the Alfons home page (ZIP, 28k)
Registration: Freeware

Lief Clennon is a computer hobbyist and Team OS/2 member currently residing in Albuquerque, NM. He can usually be found badgering his friends on IRC.


[Our Sponsor: Sundial Systems Corporation - Productivity: Relish; Mesa 2; Clearlook; DBExpert.]

Copyright © 1998 - Falcon Networking ISSN 1203-5696