diff options
Diffstat (limited to 'node_modules/chroma-js/src/conversions/rgb2lab.coffee')
| -rw-r--r-- | node_modules/chroma-js/src/conversions/rgb2lab.coffee | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/node_modules/chroma-js/src/conversions/rgb2lab.coffee b/node_modules/chroma-js/src/conversions/rgb2lab.coffee new file mode 100644 index 0000000000..8e1e70aefc --- /dev/null +++ b/node_modules/chroma-js/src/conversions/rgb2lab.coffee @@ -0,0 +1,17 @@ + +rgb2lab = () -> + [r,g,b] = unpack arguments + r = rgb_xyz r + g = rgb_xyz g + b = rgb_xyz b + x = xyz_lab (0.4124564 * r + 0.3575761 * g + 0.1804375 * b) / X + y = xyz_lab (0.2126729 * r + 0.7151522 * g + 0.0721750 * b) / Y + z = xyz_lab (0.0193339 * r + 0.1191920 * g + 0.9503041 * b) / Z + [116 * y - 16, 500 * (x - y), 200 * (y - z)] + + +rgb_xyz = (r) -> + if (r /= 255) <= 0.04045 then r / 12.92 else Math.pow((r + 0.055) / 1.055, 2.4) + +xyz_lab = (x) -> + if x > 0.008856 then Math.pow(x, 1 / 3) else 7.787037 * x + 4 / 29 |