Glossary: Difference between revisions

    From Ban Covert Modeling! wiki
    (+ == Light stage ==)
    (formatting Wikipedia quotes to {{Q}} +sourced definition of BRDF from Wikipedia + minor formats,)
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    == Bidirectional reflectance distribution function ==
    == Bidirectional reflectance distribution function ==
    '''[[w:Bidirectional reflectance distribution function]]''' or '''BRDF''' is a 7D model containing geometry, textures and reflectance of the subject.
    {{Q|The '''bidirectional reflectance distribution function''' ('''BRDF''') is a function of four real variables that defines how light is reflected at an [[w:Opacity (optics)|opaque]] surface. It is employed in the [[w:optics|optics]] of real-world light, in [[w:computer graphics|computer graphics]] algorithms, and in [[w:computer vision|computer vision]] algorithms.|Wikipedia|[[w:bidirectional reflectance distribution function|BRDF]]}}


    The seven dimensions of the BRDF are as follows: 3 cartesian X,Y,Z and 2 for the entry angle and 2 for the exit angle of the light.
    A BRDF model is a 7 dimensional model containing geometry, textures and reflectance of the subject.
     
    The seven dimensions of the BRDF are as follows:  
    * 3 cartesian X,Y,Z  
    * 2 for the entry angle
    * 2 for the exit angle of the light.


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    == Light stage ==
    == Light stage ==
    A '''[[w:light stage]]''' or '''light cage''' is equipment used for [[w:3D modeling|shape]], [[w:texture mapping|texture]], reflectance and [[w:motion capture|motion capture]] often with [[w:structured light|structured light]] and a [[w:multi-camera setup|multi-camera setup]]. (Wikipedia)
    {{Q|A '''[[w:light stage|light stage]]''' or '''light cage''' is equipment used for [[w:3D modeling|shape]], [[w:texture mapping|texture]], reflectance and [[w:motion capture|motion capture]] often with [[w:structured light|structured light]] and a [[w:multi-camera setup|multi-camera setup]].|Wikipedia|light stages}}

    Revision as of 17:01, 2 April 2019

    Bidirectional reflectance distribution function

    “The bidirectional reflectance distribution function (BRDF) is a function of four real variables that defines how light is reflected at an opaque surface. It is employed in the optics of real-world light, in computer graphics algorithms, and in computer vision algorithms.”

    ~ Wikipedia on BRDF


    A BRDF model is a 7 dimensional model containing geometry, textures and reflectance of the subject.

    The seven dimensions of the BRDF are as follows:

    • 3 cartesian X,Y,Z
    • 2 for the entry angle
    • 2 for the exit angle of the light.

    Covert modeling

    Covert modeling refers to both covertly modeling aspects of a subject i.e. without express consent.

    Main known cases are

    • Covertly modeling the human appearance into 7-dimensional [[#Bidirectional reflectance distribution function|]] model or other type of model.
    • Covertly modeling the human voice

    There is work ongoing to model e.g. human's style of writing, but this is probably not as drastic a threat as the covert modeling of appearance and of voice.


    Light stage

    “A light stage or light cage is equipment used for shape, texture, reflectance and motion capture often with structured light and a multi-camera setup.”

    ~ Wikipedia on light stages