ImagickPixel::getColorValue

(PECL imagick 2, PECL imagick 3)

ImagickPixel::getColorValue — Gets the normalized value of the provided color channel

说明

public ImagickPixel::getColorValue(int $color): float

Retrieves the value of the color channel specified, as a floating-point number between 0 and 1.

参数

color: The color to get the value of, specified as one of the Imagick color constants. This can be one of the RGB colors, CMYK colors, alpha and opacity e.g (Imagick::COLOR_BLUE, Imagick::COLOR_MAGENTA).

返回值

The value of the channel, as a normalized floating-point number, throwing ImagickPixelException on error.

示例

示例 #1 Basic Imagick::getColorValue() usage

<?php
    
$color = new ImagickPixel('rgba(90%, 20%, 20%, 0.75)');

echo "Alpha value is ".$color->getColorValue(Imagick::COLOR_ALPHA).PHP_EOL;
echo "".PHP_EOL;
echo "Red value is ".$color->getColorValue(Imagick::COLOR_RED).PHP_EOL;
echo "Green value is ".$color->getColorValue(Imagick::COLOR_GREEN).PHP_EOL;
echo "Blue value is ".$color->getColorValue(Imagick::COLOR_BLUE).PHP_EOL;
echo "".PHP_EOL;
echo "Cyan value is ".$color->getColorValue(Imagick::COLOR_CYAN).PHP_EOL;
echo "Magenta value is ".$color->getColorValue(Imagick::COLOR_MAGENTA).PHP_EOL;
echo "Yellow value is ".$color->getColorValue(Imagick::COLOR_YELLOW).PHP_EOL;
echo "Black value is ".$color->getColorValue(Imagick::COLOR_BLACK).PHP_EOL;

?>

以上示例会输出：

Alpha value is 0.74999618524453

Red value is 0.90000762951095
Green value is 0.2
Blue value is 0.2

Cyan value is 0.90000762951095
Magenta value is 0.2
Yellow value is 0.2
Black value is 0