diff options
| -rw-r--r-- | lib/paperclip/color_extractor.rb | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/lib/paperclip/color_extractor.rb b/lib/paperclip/color_extractor.rb index 44fe5ff1d..c8bb771a0 100644 --- a/lib/paperclip/color_extractor.rb +++ b/lib/paperclip/color_extractor.rb @@ -5,6 +5,7 @@ require 'mime/types/columnar' module Paperclip class ColorExtractor < Paperclip::Processor MIN_CONTRAST = 3.0 + ACCENT_MIN_CONTRAST = 2.0 FREQUENCY_THRESHOLD = 0.01 def make @@ -26,8 +27,9 @@ module Paperclip foreground_palette.each do |color| distance = ColorDiff.between(background_color, color) + contrast = w3c_contrast(background_color, color) - if distance > max_distance + if distance > max_distance && contrast >= ACCENT_MIN_CONTRAST max_distance = distance max_distance_color = color end @@ -77,8 +79,8 @@ module Paperclip private def w3c_contrast(color1, color2) - luminance1 = (0.2126 * color1.r + 0.7152 * color1.g + 0.0722 * color1.b) + 0.05 - luminance2 = (0.2126 * color2.r + 0.7152 * color2.g + 0.0722 * color2.b) + 0.05 + luminance1 = color1.to_xyz.y * 0.01 + 0.05 + luminance2 = color2.to_xyz.y * 0.01 + 0.05 if luminance1 > luminance2 luminance1 / luminance2 |