Thread

1. vermarish · 1785859472 · focus · HN ↗

   This is beautiful work! First, I thought this would involve using PCA to go from 3D to 2D, which would result in an easier selector to use, but at the expense of representing every person.

   Then, I thought this would stop at using the U-space vectors (the ones that form the basis of the PCA image) and their corresponding ellipse to form our color space, but no, the function fitting is a very slick idea, even if it was executed by hand.

   Lastly, I love the presentation of sampling from different r values. Whether you sample from a fixed r value or a range of r values, I bet this has great applications in game design or animation.

   I still don't quite get the manual data labeling process at the beginning? It seems like it would encode some bias, but the consistency of the first point cloud and the results certainly speak for themselves.

   1. dr_scully · 1785860437 · focus · HN ↗

      If you look at my doctoral thesis, in fact skin colour can be parametrised using melanin and haemoglobin concentration; which it means it is indeed (roughly) two dimensional. This allows you to invert the colour of a pixel and identify someone’s chromophore concentration. This is based on previous work of others cited in the thesis.

      <a href="https:&#x2F;&#x2F;discovery.ucl.ac.uk&#x2F;id&#x2F;eprint&#x2F;10093345&#x2F;" rel="nofollow">https:&#x2F;&#x2F;discovery.ucl.ac.uk&#x2F;id&#x2F;eprint&#x2F;10093345&#x2F;

      1. GolDDranks · 1785860788 · focus · HN ↗

         I&#x27;ve heard that the so-called &quot;yellowish&quot; skin color that non-tanned East Asians tend to have, is due to relative abundance of subcutaneous fat. If that&#x27;s true, is that captured by the haemoglobin dimension or is it a yet another degree of freedom?

         1. Joel_Mckay · 1785862874 · focus · HN ↗

            All skin is slightly translucent, and color&#x2F;tones forms a gradient across the surface of the skin. Your upper cheeks and forehead are usually slightly reddish, and the chin&#x2F;neck are slightly bluish.

            People only turn yellow if they have kidney or liver damage. However, some distinctive features like Lucy Liu&#x27;s natural freckles are tough to draw right.

            We looked around a lot for a procedural texture&#x2F;shader to help make the project characters look less sickly, and please also consider supporting the persons work if you are able:

            <a href="https:&#x2F;&#x2F;kuhantilope.gumroad.com&#x2F;l&#x2F;ultimate-skin" rel="nofollow">https:&#x2F;&#x2F;kuhantilope.gumroad.com&#x2F;l&#x2F;ultimate-skin

            Best of luck =3

            1. iwontberude · 1785864974 · focus · HN ↗

               &gt; People only turn yellow if they have kidney or liver damage.

               This is not true. Roughly 5% of people have Gilbert&#x27;s Syndrome which is genetic, metabolic abnormality where the bilirubin from dead blood cells are conjugated slower than the baseline patient leading to yellowing of the skin. It is not due to liver damage or disease and is a benign condition. Not to mention there is carotenemia from eating too many carrots or squash -- again not kidney&#x2F;liver damage related.

               1. Joel_Mckay · 1785865754 · focus · HN ↗

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