Print

Print


At 03:52 PM 4/18/2003 -0400, Aaron Z Snyder wrote:
>Has anybody ever written the Dolby encode/decode algorithm in Windows-based
>software?
>
>The question arose when a friend of mine told me about some orphaned Dolby
>B-encoded tapes. These apparently are reel-to-reel and without calibration
>tones. Granted, without the calibration tone, decoding of the tapes would be
>pure guesswork. However, a computer-based program would at least allow
>non-real-time experimentation so that a plausible reference level could be
>established.

I have approximated the Dolby B algorithm in CoolEdit Pro with poor
results. I do not have the process specs and, as you say, without the
calibration tone there is a major piece of guesswork but neither of those
was fatal. Despite fiddling with the parameters, I could not get the
dynamic compressor to match the Dolby in dynamics. Ultimately, I dusted off
my external Dolby B processor and did it in analogue; it was easier and I
persuaded myself that it was more accurate.


Mike
[log in to unmask]
http://www.mrichter.com/