August 28, 2002

   Welcome to version 1.00 of the PalancarWare DeDC VST plug-in for
   BeOS. Installation and usage notes are below.


History

   v1.00 - 21Dec2001 - first release.


The Palancar CD-Ware License

   This product is copyright (c) 2000-2002 by Darrell Burgan, with all
   rights reserved world-wide.

   This product is not public domain. I developed all content in this
   product, with any exceptions noted below, and am the sole owner of
   the copyright.  I'm granting you, however, an almost-free license to
   use it on as many devices as needed, for any legal purpose, subject
   to these terms:

      This product is licensed as-is, without warranty of any kind. I
      disclaim all legal liability.  If you use it, you do so at your
      own risk and are responsible for ensuring it works to your
      satisfaction.  Why do I not warrant it?  I'm just an individual
      struggling musician like everybody else, and I simply don't have
      the resources to provide an adequate warranty.  My warranty
      wouldn't be of much use to you anyway.

      This license is granted as "CD-ware".  What this means is that you
      have 30 days to use this product and evaluate whether it works to
      your satisfaction, and whether you like it and intend to use it.
      If you decide to continue to use it beyond 30 days, or if you use
      it in a project from which you will derive profit before 30 days
      have elapsed, I ask you to please go to my music web site (see
      below) and purchase one (or more) of my CDs as compensation. The
      CDs are very low priced, and can be purchased from anywhere in the
      world.  How do I know whether you've done this or not?  I don't.
      This is on the honor system, folks. If you like the results of my
      hard work, I don't think a measly CD is too much to ask. If you
      use multiple products, then purchasing multiple CDs is suggested.
      Use your best judgment as to how many you ought to purchase.  But
      I do request you purchase at least one.

      If you honestly cannot afford to purchase a CD but still want to
      use this product, then please contact me and we'll figure
      something out.

      The license does not imply nor suggest ownership of this product.
      I'm licensing the product's use, not selling ownership of the
      product. The license is subject to alteration or revocation at any
      time, at my discretion, with 30 days notice given here.  I can
      foresee no reasonable scenario where this could occur, but I want
      to make clear who owns the intellectual property.

      Note also that you are licensed only to use this product for the
      purpose it is designed, not to distribute it in any way, alter it
      in any way, or use it in any other way. If you want to distribute
      it, you need to link to "http://www.palancar.net/palancarware" in
      its entirety, and should not distribute the files nor point
      directly to them from any web site.

      If you disagree with any of the terms of this license, then you
      should not use this product.  If you use the product, you have
      implicitly agreed to these licensing terms.  If you are the least
      bit uncertain about these terms or would like to explore
      alternatives, please contact me and we'll figure something out.

   Other folks' copyrights:

      Portions copyright (c) Steinberg GMBh

      Credit is given to the Music-DSP Archive for certain algorithms
      used in this product.  The archive can be found at:
      http://www.smartelectronix.com/musicdsp/.

   Palancar music CDs can be purchased at:

      http://www.ampcast.com/palancar

   Whew!  Sorry for all the lawyer stuff, but you know how it is in
   these days of Napster and Gnutella.  I hope you enjoy this product,
   and I hope you understand that I've put far more time into it than I
   would ever hope to receive back financially under this license.  In
   other words, I'm not doing this for the money, folks...


Installation

   Simply copy the file to the VST plugins directory of the VST media wrapper.
   I've not included an installer because this installation is so simple, to
   minimize download time.


The Plugin

   DeDC is one of the simplest plugins you can imagine.  It
   automatically reduces/removes the DC offset from an input signal,
   without the user having to know anything about what a DC offset is or
   how to remove it.

   For those who are interested, DC offset is actually a very simple
   thing.  A DC offset occurs when there is more signal in the positive
   domain than the negative domain, or vice versa.  Another way of
   viewing this is to imagine that we take the average of all samples
   that have values greater than zero, then the average of all samples
   less than zero; if the averages are not equal, a DC offset exists.

   Now, why does one care if a DC offset exists?  The biggest reason is
   simply that it steals available headroom.  Obviously, if there is
   more signal on one side of zero than on the other, a clipping-free
   normalization operation cannot amplify the signal as much as if the
   signal were balanced vis-a-vis the zero axis.  By reducing the DC
   offset, one has more headroom for dynamic expansion.  Another reason
   is that large DC offsets can make it more difficult to keep signals
   in phase with one another.

   DeDC employs a clever mathematical algorithm which can analyze a
   signal on the fly and apply DC offset correction to it.  It's
   important to note that DC offset correction is most easily performed
   in non-realtime, when the program has access to all samples at once.
   DeDC, obviously, does not have this luxury as it is a VST-compatible
   plugin.  For this reason, DeDC will not always remove ALL DC offset;
   it's possible that a particularly weird signal might confuse the
   algorithm and prevent complete DC offset removal.  That said, the
   plugin should always reduce the DC offset, if not eliminate it
   completely.

   There is only one control:

      Input Gain - this controls the amount of amplification (or gain
      cut) that occurs on the input signal before the DC offset
      correction is applied.


Using the Plugin

   Simply apply DeDC against your input signal, and any DC offset
   offset should be significantly reduced or eliminated.

   A couple of tips on using the plugin:

      To avoid problems, set the input gain once and keep it constant
      for the duration of the processing (i.e. don't automate the input
      gain). For obvious reasons, if one is changing the gain on the
      fly, the algorithm which determines DC offset could be affected
      and produce anomalous results.

      DC offset can creep into your signal from a variety of sources.
      For example, many popular VST plugins have the side effect of
      creating significant DC offset.  This is a natural side effect of
      many DSP algorithms.  As a result, you may wish to run DeDC on
      your tracks repeatedly as you work with them, to ensure maximum
      headroom at all times.  There is no penalty for re-running DeDC on
      a signal, so feel free to run it as often as desired.


Support

   Due to the number of VST hosts and operating systems in the world,
   there is no way I can possibly test it with all possible software
   products.  If you run into any snags, please contact me at:

      Darrell Burgan
      PalancarWare
      darrell@palancar.net
      http://palancarware.palancar.net/
      
   For BeoS specific support, contact Xentronix at info@xentronix.com,
   http://www.xentronix.com
