[PD] Skin Detection

[ydegoyon at gmail.com]

Mathieu Bouchard wrote:
> On Thu, 17 Jun 2010, João Pais wrote:
>
>>> I would be very careful with your conception of skin if your going
>>> visual sensing, as it would be very difficult to make a skin detector
>>> that does not privilege certain skin tones.
>> like in http://www.youtube.com/watch?v=t4DT3tQqgRM ?
>
> Typically, face recognition involves using statistics about what a 
> face looks like, so if the programme ships with a precomputed neural 
> network and no tool to help add custom faces, chances are that it will 
> miss a lot of people. I haven't tried such tools but I could guess 
> that it would also miss people with unusually large beards and large 
> mustaches,
>
>   http://esoterisme-exp.com/Section_main/Collection4/612-esoexp30.jpg
>   http://blogue.branchez-vous.com/archives/doc-mailloux.jpg
>
> A large mustache can cut a face in two, especially with certain angles 
> and lightings. A large beard changes a face so much, that while 
> googling for the latter guy, the first text I saw was someone 
> wondering "what his face looks like" (without beard). A photoshop 
> speculation :
>
>   http://blogue.branchez-vous.com/upload/2007/04/doc_mailloux.jpg
>
> But algorithms can't come up with that kind of picture, and even from 
> a human, there's always a possibility that the chin is wrong, if 
> there's not enough of a hint of it on the picture.
>
> Finally, black faces have much lower contrast, especially if the 
> camera has a narrow range of intensity and is auto-adjusting to the 
> average brightness of the scene. On top of that, any shininess of the 
> skin can make reflections that can confuse the algorithm a lot.
>
>  _ _ __ ___ _____ ________ _____________ _____________________ ...
> | Mathieu Bouchard, Montréal, Québec. téléphone: +1.514.383.3801
> ------------------------------------------------------------------------
>
> _______________________________________________
> Pd-list at iem.at mailing list
> UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
>   
---- +++

face recognition is not based on colour in any sense,
it is based on number and orientation of segments
of the contours, at least in haar's algorithm ...

---- ----