The most interesting point made in the article (for me) is that the presence of noise/grain - which effectively reduces real detail in an individual image - can actually improve the perceived detail across time with high frame rates.
At first, I thought this extra "detail" could be explained as an illusion (since noise/grain can mask a lack of resolution), but then I read the abstract quoted near the end of the article:
"...visual cortical cell responses to moving stimuli with very small amplitudes can be enhanced by adding a small amount of noise to the motion pattern of the stimulus. This situation mimics the micro-movements of the eye during fixation and shows that these movements could enhance the performance of the cells"[1]
So if I understand right, since the biological systems are tuned to extract extra detail via supersampling across time, and a small amount of noise/grain can enhance that ability (mimicking natural movement of the eye), it actually helps our visual system extract more real detail.
It seems counterintuitive to add noise for more detail, but the explanation is fascinating.
[1] Stochastic resonance in visual cortical neurons: does the eye-tremor actually improve visual acuity? – Hennig, Kerscher, Funke, Wörgötter; Neurocomputing Vol 44-46, June 2002, p.115-120
Actually, these are two completely distinct phenomena.
Dithering exists in both the visual and the audio realms, as corysama pointed out in their linked article [1]. The term's use is identical in both realms, but neither is really related to stochastic resonance.
Dithering is a technique of adding noise to disguise sampling boundaries. It hides unrealistic artifacts from digital downsampling of analog signals, but it does not add more realistic detail. Critically, it does not increase the signal-to-noise ratio.
The phenomenon being described here occurs on a biological level. As described above, the additional noise improves your visual acuity. That is, you can extract /additional/ details with the noise added which could not be resolved before. This is due to a nonlinear change invoked in the system receiving the signal, not from the change to the signal itself. So, while adding the noise initially decreased the signal-to-noise ratio, the overall effect on the entire system is a increase in signal-to-noise ratio.
Here the mechanism, explained in the Henrig paper, appears to be purely biological, but stochastic resonance is not strictly a biological phenomenon; it can also be seen in the electrical domain [2].
Wow, I never knew. I have this a a low level. Always have.
Here's a mildly interesting thing: Say you are at a stop light, and you want to get the jump on the other guy.
Jiggle your eyes rapidly around the light, and you will pick up the change more quickly than other people do.
Eyes do not have frame rates. They sample in a staggered fashion, some rods / cones, others, inner eye priority, outer eye lower priority, with movement getting priority overall and detail.
At first, I thought this extra "detail" could be explained as an illusion (since noise/grain can mask a lack of resolution), but then I read the abstract quoted near the end of the article:
"...visual cortical cell responses to moving stimuli with very small amplitudes can be enhanced by adding a small amount of noise to the motion pattern of the stimulus. This situation mimics the micro-movements of the eye during fixation and shows that these movements could enhance the performance of the cells"[1]
So if I understand right, since the biological systems are tuned to extract extra detail via supersampling across time, and a small amount of noise/grain can enhance that ability (mimicking natural movement of the eye), it actually helps our visual system extract more real detail.
It seems counterintuitive to add noise for more detail, but the explanation is fascinating.
[1] Stochastic resonance in visual cortical neurons: does the eye-tremor actually improve visual acuity? – Hennig, Kerscher, Funke, Wörgötter; Neurocomputing Vol 44-46, June 2002, p.115-120