Class: Color::YIQ

### Home Classes Methods

### In Files

- lib/color.rb
- lib/color/yiq.rb

### Parent

Object

### Methods

- ::from_fraction
- ::new
- #==
- #brightness
- #to_grayscale
- #to_greyscale
- #to_yiq

### Files

- Changelog
- Install
- README

### Class/Module Index

Quicksearch

- Color
- Color::CMYK
- Color::CSS
- Color::GrayScale
- Color::GreyScale
- Color::Palette
- Color::Palette::Gimp
- Color::Palette::MonoContrast
- Color::RGB
- Color::RGB::Metallic
- Color::YIQ

No matching classes.

# Color::YIQ

A colour object representing YIQ (NTSC) colour encoding.

### Attributes

i[RW]
q[RW]
y[RW]

### Public Class Methods

from_fraction(y = 0, i = 0, q = 0) click to toggle source

Creates a YIQ colour object from fractional values 0 .. 1.

    Color::YIQ.new(0.3, 0.2, 0.1)

    # File lib/color/yiq.rb, line 17
    def self.from_fraction(y = 0, i = 0, q = 0)
      color = Color::YIQ.new
      color.y = y
      color.i = i
      color.q = q
      color
    end

new(y = 0, i = 0, q = 0) click to toggle source

Creates a YIQ colour object from percentages 0 .. 100.

    Color::YIQ.new(10, 20, 30)

    # File lib/color/yiq.rb, line 28
    def initialize(y = 0, i = 0, q = 0)
      @y = y / 100.0
      @i = i / 100.0
      @q = q / 100.0
    end

### Public Instance Methods

==(other) click to toggle source

Compares the other colour to this one. The other colour will be converted to YIQ before comparison, so the comparison between a YIQ colour and a non-YIQ colour will be approximate and based on the other colour's to_yiq conversion. If there is no to_yiq conversion, this will raise an exception. This will report that two YIQ values are equivalent if all component colours are within 1e-4 (0.0001) of each other.

    # File lib/color/yiq.rb, line 41
    def ==(other)
      other = other.to_yiq
      other.kind_of?(Color::YIQ) and
      ((@y - other.y).abs <= 1e-4) and
      ((@i - other.i).abs <= 1e-4) and
      ((@q - other.q).abs <= 1e-4)
    end

brightness() click to toggle source

    # File lib/color/yiq.rb, line 53
    def brightness
      @y
    end

to_grayscale() click to toggle source

    # File lib/color/yiq.rb, line 56
    def to_grayscale
      Color::GrayScale.new(@y)
    end

Also aliased as: to_greyscale
to_greyscale() click to toggle source
Alias for: to_grayscale
to_yiq() click to toggle source

    # File lib/color/yiq.rb, line 49
    def to_yiq
      self
    end

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