Pete wrote:
> Oversampling in audio is a hardware implemented function, which is
> really only of any worth when it's applied at the recording stage.
> The primary use is to make the 'brick wall' low-pass filter more
> effective (and cheaper to make) prior to the A to D conversion stage.
Er. Sorry, but the same brick wall low pass filter is also needed after
the D/A in a CD player to eliminate aliasing errors on the output, otherwise
you could destroy your hifi power amp by feeding it high levels of inaudible
frequencies - as well as their harmonics. But this is a scanning list so
let's not dwell on it anymore?
>A researcher at Microsoft has shown, crudely, how oversampling can be
> used to reduce aliasing in digital HDTV without increasing the
> bandwidth to accomodate high sampling rates
I'd be interested to know how this was done.
> It wouldn't take much to combine an area of 4 samples into one,
> using a true RMS algorithm. This would mean that the scanner
> would output only 5,000 dpi, but the brightness level could be
> much more accurately represented than simple area integration allows.
Unfortunately, the hardware would probably be beyond affordability for
most of us. :(
Rob
Rob Geraghty [EMAIL PROTECTED]
http://wordweb.com
