Program for dithering audio?
Reply #21 – 2006-09-01 14:38:07
noise power relative to full rectangular dither (+/-0.5) under the assumption the noise is NOT correlated before shaping (ie no non-linear distortions):rectangular dither: +/- 0.5 -0.00 dB (obviously) rectangular dither: +/- 0.4 -0.86 dB rectangular dither: +/- 0.3 -1.67 dB rectangular dither: +/- 0.2 -2.37 dB rectangular dither: +/- 0.15 -2.64 dB rectangular dither: +/- 0.1 -2.84 dB rectangular dither: +/- 0.05 -2.97 dB rectangular dither: +/- 0.0 -3.01 dB Decide for yourself whether a given dither level is worth the risk of harmonic distortions. I'd probably try 0.2 next time because below that the noise power doesn't drop significantly. Is there any interest in an interactive/live noise shaper design tool? I could make the proggy a bit more user-friendly if anyone whishes to have a play ... BTW: I'm totally fine with 12 bits at 44kHz with noise shaping enabled and moderate dithering. I really can't distinguish it from the 16 bit version using ear buds. It may be due to my computer's fans. 2Bdecided: Could you post a file containing TPDF dithered silence using the same noise shaper you used to make the 6bit/7bit files? I'm interested in what the shaper actually does. I have no CE Pro Edit: I think it's possible to prove that a certain dither level (below the alredy known-to-be-safe levels) is secure given the impulse response of the noise shaper -- me needs to think more about it. Edit2: The old Beatles song may already contain enough noise so one does not need a dither. It'd be nice to have a 16 bit reference.