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[JavaScript - Determine if Hex Color is Light or Dark] JavaScript - Determine if Hex Color is Light or Dark #JavaScript
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| function lightOrDark(color) { | |
| // Check the format of the color, HEX or RGB? | |
| if (color.match(/^rgb/)) { | |
| // If HEX --> store the red, green, blue values in separate variables | |
| color = color.match(/^rgba?\((\d+),\s*(\d+),\s*(\d+)(?:,\s*(\d+(?:\.\d+)?))?\)$/); | |
| r = color[1]; | |
| g = color[2]; | |
| b = color[3]; | |
| } | |
| else { | |
| // If RGB --> Convert it to HEX: http://gist.github.com/983661 | |
| color = +("0x" + color.slice(1).replace( | |
| color.length < 5 && /./g, '$&$&' | |
| ) | |
| ); | |
| r = color >> 16; | |
| g = color >> 8 & 255; | |
| b = color & 255; | |
| } | |
| // HSP equation from http://alienryderflex.com/hsp.html | |
| hsp = Math.sqrt( | |
| 0.299 * (r * r) + | |
| 0.587 * (g * g) + | |
| 0.114 * (b * b) | |
| ); | |
| // Using the HSP value, determine whether the color is light or dark | |
| if (hsp>127.5) { | |
| return 'light'; | |
| } | |
| else { | |
| return 'dark'; | |
| } | |
| } | |
| bgColor = "#EE7AB7" | |
| brightness = lightOrDark(bgColor); | |
| console.log(brightness, hsp) |
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