Talk:Color system

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All belong to semantic frame SKARI_FREIME:

  • skari - x1 has color x2 according to x3
  • ? - x1 has hue x2 according to x3
  • ? - x1 has colorfulness x2 according to x3
  • ? - x1 has chromacity x2 according to x3
  • ? - x1 has saturation x2 according to x3
  • ? - x1 has lightness x2 according to x3
  • ? - x1 has brightness x2 according to x3
  • ? - x1 has chrominance x2 according to x3


  • ? - x1 has gamut (span of/generated by color parameters) x2 according to x3. Should belong to SKARI_FREIME or not?
  • ? - (needed?) x1 is a shade, tint, dye, variety of x2
  • nu'ansa = x1 (entity) is a nuance, minor distinction of x2 (entity)

skari1 is an object, skari2 is a prototype object like lo ciblu or lo xunre. There are no core words for "color" in Lojban, only derivatives.

How do we reflect "tone", "tint", and "shade" (which are greyness/black-joi-white-ness, whiteness, and blackness of a color, respectively) rather than hue (which is redness, greenness, blueness, and sometimes: yellowness, orangeness, and violetness; I would also argue for indigoness (which is actually the light blue in a rainbow, whereas "blue" is the dark blue) and a generalized "a culturally identified and distinct color in a rainbow/spectrum"-ness).

We might want to eventually create a word (maybe lujvo) for "gamut" (roughly: a span of/generated by color parameters). What would be its place structure?

Representing Color Space as a 'Vector' Space

Colors as perceived by humans can be described as a linear combination of registered excitations in eye cells which approximately correspond to the colors red, green, and blue.

Let {kratiju} mean "$x_1$ is a (mathematically explicit/concrete) representation of (abstract mathematical object/physical quantity) $x_2$ according to system/basis/generators/interpretation rules $x_3$ under conditions/in context $x_4$", where:

  • kratiju1 must be presented as an ordered tuple with an ordering which is governed by some implicit ordering of the elements of kratiju3 (if it is an unordered set) or according to the explicit/presented ordering thereof (if it is an ordered formal tuple of basis/generating elements or a rule which provides an ordering explicitly)
  • These words are fairly loose mathematically. For example, many things may be interpreted as a "concrete representation", the abstract objects which are kratiju2 may be fairly diverse (they need not be strictly vectors, for example), and kratiju3 need not be a basis in a strict sense although it must contain kratiju2 (and be able to support kratiju1 thereof) in its 'span'.
  • Example: kratiju2 might be a vector, but kratiju1 might be an ordered list/tuple such as (1,0,1) in some basis (specified by kratiju3). An ordered list is not a vector, but it can be understood to mean one. (Alternatively, in some contexts, it might indicate a point in space, or something else entirely). Likewise, a matrix is not really a square of numbers, that is just the representation of a given matrix in a given basis; the representation might change as the basis changes but the mateix would remain constant - or the reverse may be true under other conditions. Moreover, a square of numbers need not behave as a matrix does and therefore may not represent one. Lojban presently conflates these ideas of concrete representation and abstract represented object; technically {jo'i}, {pi'a}, {sa'i}, {ce'o} all form representations, technically. Usually abstract objects are denoted by single letters/symbols. Concrete representations might be arrays or pictures/diagrams (such as would be the case for a graph/network).

Then "this thing is Red at 50% of 'intensity', Green at 30%, Cyan at 10%, Blue at 10%", where "intensity" is used loosely or colloquially (as a measure of stimulation/excitation/content/presence), approximately and non-bindingly and non-canonically translates to:

"le se skari be ti be'o ku se kratiju be li jo'i pi mu boi pi ci boi pi pa boi pi pa te'u ku le cmurau vektori be le ni xunre be'o ce'o le cmurau vektori be le ni crino be'o ce'o le cmurau vektori be le ni blanu be'o ce'o le cmurau vektori be le ni cicna".

I think that that is pretty good. There might be some small hidden assumptions and it might be a bit wordy in other ways, and there might be some problems of which I cannot quite think right now, but that is approximately good. It may not be a home run, but the bat is making contact with the ball, so to speak.

These are some issues/comments which I see with this translation:

  • Color space is technically not a vector space, so {vektori} is somewhat abusive.
  • I am not sure that I like "cmurau" for "unit/directional/normalized" in this sense.
  • The coefficients are in [0,1]. This is pretty natural.
  • {jo'i} and/or {ce'o} might have very slight issues with abusive or mistranslated usage here.
  • The {ni} clauses might be a bit off.
  • The use of {skari} is possibly wrong, subject to observations made in this page in general.

Krtisfranks (talk) 23:41, 8 May 2016 (PDT)