On Sat, 17 May 2008 22:39:00 -0800, glen herrmannsfeldt
<[email protected]> wrote:

>Ben Bradley wrote:
>(someone wrote)

....

>>>It is a recording with a live audience, and the background isn't all
>>>that quiet, anyway. It would be nice, though. Do others do it?
>
>> Yes, I'm pretty sure most all audio editing software (everything
>> from Audacity to Pro Tools) have been doing it as I described for many
>> years now.
>
>This was pretty simple and free. This is personal, and the
>budget is low.

Audacity is free, you might want to play around with it:
http://audacity.sourceforge.net/

>
>> It might be easier to write some script file for an audio editing
>> program to do what you want. I don't know what programs have what
>> features nowadays, but the old Cool Edit 2000 has/had scripting so you
>> could do several automated things with audio files.
>
>If I want to add dither can I use an array of some reasonable
>length as a periodic data stream?

since it's likely "below the threshold of hearing", a second's
worth of random numbers (44,000) ought to do (if it's loud enough to
hear, the ear will be able to hear the repeated nature of the noise),
but a simple what's-it-called, 'congruence' random number generator
can generate adequate numbers with minimal code execution per sample.
If you filter the noise for noise-shaping, the filter code will take
more CPU cycles.

>Generating enough random
>numbers for a whole CD might take a while.
>
>-- glen