Fhg Radium MP3 codec FAQ
June 26, 1999

Q : How do I make MP3s with this codec?
A : The codec is similar to a driver .. you use it inside any codec
    capable program. First, you go into the 'Save as' menu of your
    audio program and choose 'Mpeg layer-3' for format.

Q : What programs are 'codec capable'?
A : Here is a parial list of programs that can use external codecs :
    Audiograbber, WinDAC, Soundforge, Wavelab, Acid, CoolEditPro,
    Jetaudio, MP3 compressor, MPEG Layer-3 Producer 1.1, Windows sound
    recorder, Audioactive MP3 (with the radium converter) and more.

Q : How does the 'Radium codec' quality compare to other encoders?
A : Audioactive, Opticom Producer and the Radium codec all essentially
    use the same engine - they will all create the same quality of output
    if given the same input and options. These Fraunhofer codecs are
    widely recognized as being the best mp3 codecs available.

Q : How is the Radium codec better than Audioactive?
A : The advantage is that the Radium codec is a little faster, has more
    stereo mode options, has more encoding bitrates, and is external
    (it can be used from inside many other programs.) 

Q : Some programs save my compressed files as '.wav' files. Why?
A : These are still mp3 files, but with a WAV header. You can change the
    extension to mp3 ... they work exactly the same.

Q : What is the 'priority' setting I see in the codec control panel?
A : Most programs 'save' dialog have a list of codecs you can use. Setting
    a higher priority will put that codec closer to the top of the list. In
    some automated applications if two codecs have the same name the higher
    priority codec will be used.

Q : Where is the codec control panel?
A : Control Panel > Multimedia > Devices > Audio Compression Codecs
    Then you'll see a 'Fraunhofer IIS MPEG Layer-3 Codec (professional)'
    Click on that and you'll see a 'settings button'. For your convenience
    we've made a little shortcut icon to this in the Radium codec installer.

Q : The Radium codec uses the same engine as Audioactive and Opticom Producer, 
    but it supports more bitrates. How is it possible? Will I be able to play
    these bitrates?
A : Yes. This version of codec adds 224 kBit/s and 320 kBit/s rates. They are
    ordinary MP3 rates and all players should support them. Some other
    encoders like Blade or Xing support these rates as well. Audioactive and
    Opticom Producer don't allow the user to set these bitrates for some
    unknown reason, even though they are supported internally.

Q : How do i select between HQ and LQ modes?
A : If a certain program has no place to select between HQ or LQ encoding
    then it's safe to say that 'HQ' gets used. Soundforge for instance uses
    HQ mode when using this codec and most similar programs will also. 
    Sidenote for developers : HQ/LQ mode is controled by the Real-time
    flag in codec initialization. 

Q : What is HQ mode exactly?
A : HQ stands for 'High Quality'. HQ mode takes a little longer, because
    it tries to store the sound in the most efficient way. It increases
    the quality without making the resulting MP3 file any larger.

Q : I want to use a codec for a commercial project. Is the Radium codec legal?
A : In short, no. The Radium codec is derived from software owned by Fraunhofer.
    The closest legal equivalent would be to purchase Audioactive Production
    Studio (www.audioactive.com)  If you use software regularly or for any
    commercial projects you should ALWAYS purchase a legal copy!
 
Q : What's the difference between the various stereo modes?
A : It's important to understand the difference between Stereo and Joint Stereo.
    'Joint Stereo' modes take advantage of the similarities between the L+R
    channels. This allows more bits to be used in other areas and in many cases
    this can give an overall gain in encoding quality. Almost all encoders use
    joint stereo when encoding at 128 kbits.

    Joint stereo has 2 submodes called IS and MS. 'Joint Stereo IS' destroys
    phase information and shouldnt be used for high-quality encoding.
    'Joint Stereo MS' means Middle/Side and is OK for use in most encoding.

    However, for some audio, Joint Stereo MS may create a 'flanging' or
    'swishing' effect. In these cases it's better to use 'Stereo mode'. This
    mode creates 2 independent channels for both left and right. When stereo
    mode is used, you should also use a higher bitrate (160 or 192 kbits) -
    Stereo mode will allocate about half of this bitrate for each channel.

    In summary, for most audio, Joint Stereo MS at 128 or 160 kbits should be
    fine. If your audio is especially 'wide' and creates flange you should use
    'Stereo' mode. You can change these modes in the Radium codec control panel.

Q : I installed the codec before, now its gone! What happened?
A : Microsoft's "Media Player" update will remove pro codecs. Repeat after
    me : Microsoft installers are infintely stupid. Just re-run the Radium
    codec installer.

Q : In some 'save' dialogs i have more than one 'MPEG layer-3' listed. Why?
A : Simply, you may have more than one mp3 codec installed. Check by going
    to 'Control Panel > Multimedia > Devices > Audio Compression Codecs'.
    If you have a 'decode only' or 'advanced' codec you can remove them -
    they're no longer needed. (The Radium codec will do decoding as well).

Q : What is the history of this codec. How was it made?
A : There are 2 types of codecs - internal and external. In 1996 Fraunhofer
    released the first EXTERNAL Mpeg Layer-3 codec. Using that codec, *any*
    program with codec support (like SoundForge and Audiograbber) could make
    Mp3s. But that was the last external MP3 codec Fraunhofer released.

    Since then Fraunhofer have much improved their Mpeg Layer-3 technology
    but now only license it for INTERNAL use in 'Opticom Mp3 Producer Pro'
    and 'Audioactive Production Studio'. With this release igNorAMUS has
    taken the internal Producer Pro codec, and made it external again. At
    the same time he made some assembly level optimizations to the code to
    get between 5% to 12% speed increase when using 'HQ' mode on an Intel
    Pentium CPU. (See the graph included in the release). Note that these
    assembly optimizations do not affect the sound quality any - the output
    will still remain exactly the same as output from Opticom Mp3 Producer
    Pro v2.1

adium 1999 - Live freely. Distribute freely.
