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.
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