[PD] editing pd silence - dither

Mathieu Bouchard matju at artengine.ca
Sun Oct 23 22:04:58 CEST 2011

Le 2011-10-23 à 11:36:00, Marvin Humphrey a écrit :

> In that image, the "24-bit gradient" would be analogous to the full 
> width audio signal prior to bit depth reduction, the "8 bit gradient, 
> dithered" would be analogous to dithered audio, and the "8 bit gradient" 
> displaying obvious color banding would be analogous to truncated audio.

I understand all of that already, but my impression is that it's more like 
making a 24-bit gradient use dithering so that it looks more like a 48-bit 
gradient. Would it make a perceptual improvement if you did so ?

I recall that the audio dithering technique worked really great on 
PC-Speakers running on a 1-bit DAC (it's called an on/off switch). But 
that's because it used only a 1-bit device. If the device already has 16 
bits, it takes silly mistakes to emphasise the truncation error so much 
that it can be heard.

E.g. if you have a fully 16-bit-digital volume control on an amp, and the 
amp has a big volume range and you only use the quiet range, the effective 
number of bits can down a lot.

| Mathieu BOUCHARD ----- téléphone : +1.514.383.3801 ----- Montréal, QC

More information about the Pd-list mailing list