dithering

[SumAnuT]

Evo nadjoh i kod ovog lika da je periodican ...
Ako ih ne mozes pobediti, pridruzi im se, nista mi drugo ne preostaje
Izvinjavam se sto nisam verovao.

Since the quantization error is periodic, it is a distortion of the signal and is therefore directly related to the signal itself. Our brains are quite good at ignoring unimportant things. For example, you walk into someone's house and you smell a new smell - the way that house smells. After 5 minutes you don't smell it anymore. The smell hasn't gone away - your brain just ignores it when it realizes that it's a constant. The same is true of analog tape noise. If you're like most people you pay attention to the music, you stop hearing the noise after a couple of minutes. Your brain is able to do this all by itself because the noise is unrelated to the signal. It's a constant, unrelated sound that never changes with the music and is therefore unrelated - the brain decides that it doesn't change so it's not worth tracking. Distortion is something different. Distortion, like noise, is typically comprised entirely of unwanted material (I'm not talking about guitar distortion effects or the distortion of a vintage microphone here...). Unlike noise, however, distortion products modulate with the signal. Consequently the brain thinks that this is important material because it's trackable, and therefore you're always paying attention. This is why it's much more difficult to ignore distortion than noise. Unfortunately, quantization error produces distortion - not noise.

Zbog ovoga sto je covek napisao sam rekao da je pogresno sto su nas ucili da je to sum, jer kao sto covek rece, sum se ne menja, te mozak prestane da obraca paznju kroz neko vreme, a distorzija se menja, tj. modulise u zavisnosti od signala, pa je mozak stalno prati, zato se i dodaje sum, da bi mozak mogao da se opusti i slusa muziku.

[Bota]

Upravo to. Degradacija signala kod D/A konverzije je neminovna. Hajde onda da promijenimo karakter te degradacije pa da ona ne bude korelisana sa signalom (da bude nezavisna od signala) da bi je mozak mogao percipirati kao šum.

To se postiže dithering-om.