dithering

[SumAnuT]

Evo odgovora i na arturovo pitanje:

I once attended a seminar on digital audio measurements given by Julian Dunn. At lunch, I sat at a table of about 12 people, and one of the other participants asked me the simple question ``what do you think about dither?'' I responded that I thought it was a good idea9.1. Then the question was re-phrased - ``yes, but when do you use it?'' The answer is actually pretty simple - you use dither whenever you have to re-quantize a signal. Typically, we do DSP on our audio signals using word lengths much greater than the original sample, or the resulting output. For example, we typically record at 16 or 24 bits (with dither built into the ADC's), and the output is usually at one of these two bit depths as well. However, most DSP (like equalization, compression, mixing and reverberation) happens with an accuracy of 32 bits (although there are some devices such as those from Eventide that run at 64-bit internally). So, a 16-bit signal comes into your mixer, it does math with an accuracy of 32 bits, and then you have to get out to a 16-bit output. The process of converting the 32-bit signal into a 16-bit signal must include dither.

Remember, if you are quantizing (or re-quantizing), then you dither - every time.

http://www.tonmeister.ca/main/textbook/node596.html

Ceo sajt je vredan paznje: http://www.tonmeister.ca/main/textbook/node596.html