ParameterPerceptualWeighting
From Diracvideo
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[edit] Perceptual Weighting
Parameter name: perceptual_weighting
This parameter is used with perceptual_distance to estimate the visibility of features in an image. The human visual system is most sensitive to features at about 4 cycles/degree (about 2 mm at the distance of an outstretched arm), and becoming nearly insensitive at about 60 cycles/degree (a bit larger than the thickness of a human hair at the same distance). The encoder takes this variation in sensitivity into account while encoding. This parameter controls that behavior.
[edit] None (0)
A flat curve. Useful for any encoding that is not the final encode in an editing process, i.e., not meant for delivery to end users.
[edit] CCIR-959 (1)
The curve recommended by CCIR-959. It is meant to be used for video, so this is theoretically the best choice.
[edit] Moo (2)
This is nearly the same as the Manos-Sakrison curve, except it was reverse engineered from a graph of the Manos-Sakrison function, before I knew the analytic form.
This is, indeed, named after the bovine sound.
[edit] Manos-Sakrison (3)
A perceptual weight curve designed by Manos and Sakrison[missing citation]. This curve is designed for static images, and it's not clear how useful it is for video. However, it seems to give the best results currently.
