将CMYK颜色值和RGB颜色相互转换的PHP代码

    function hex2rgb($hex) {
    $color = str_replace('#','',$hex);
    $rgb = array('r' => hexdec(substr($color,0,2)),
    'g' => hexdec(substr($color,2,2)),
    'b' => hexdec(substr($color,4,2)));
    return $rgb;
    } // www.jb51.net

    function rgb2cmyk($var1,$g=0,$b=0) {
    if (is_array($var1)) {
    $r = $var1['r'];
    $g = $var1['g'];
    $b = $var1['b'];
    } else {
    $r=$var1;
    }
    $cyan = 255 - $r;
    $magenta = 255 - $g;
    $yellow = 255 - $b;
    $black = min($cyan, $magenta, $yellow);
    $cyan = @(($cyan - $black) / (255 - $black)) * 255;
    $magenta = @(($magenta - $black) / (255 - $black)) * 255;
    $yellow = @(($yellow - $black) / (255 - $black)) * 255;
    return array('c' => $cyan / 255,
    'm' => $magenta / 255,
    'y' => $yellow / 255,
    'k' => $black / 255);
    }

    $color=rgb2cmyk(hex2rgb('#FF0000'));