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    ImagickPixel::getColor

    (PECL imagick 2, PECL imagick 3)

    ImagickPixel::getColor — Returns the color

    Description

    public ImagickPixel::getColor(int $normalized = 0): array

    Returns the color described by the ImagickPixel object, as an array. If the color has an opacity channel set, this is provided as a fourth value in the list.

    Parameters

    normalized

    Normalize the color values. Possible values are 0, 1 or 2.

    List of possible values for normalized
    normalized Description
    0 The RGB values are returned as ints in the range 0 to 255 (inclusive.) The alpha value is returned as int and is either 0 or 1.
    1 The RGBA values are returned as floats in the range 0 to 1 (inclusive.)
    2 The RGBA values are returned as ints in the range 0 to 255 (inclusive.)

    Return Values

    An array of channel values. Throws ImagickPixelException on error.

    Examples

    Example #1 Basic Imagick::getColor() usage

    <?php

    //Create an ImagickPixel with the predefined color 'brown'
    $color = new ImagickPixel('brown');

    //Set the color to have an alpha of 25%
    $color->setColorValue(Imagick::COLOR_ALPHA, 64 / 256.0);

    $colorInfo = $color->getColor();

    echo     "Standard values".PHP_EOL;
    print_r($colorInfo);

    $colorInfo = $color->getColor(1);

    echo     "Normalized values:".PHP_EOL;
    print_r($colorInfo);

    ?>

    The above example will output:

    Standard values
Array
(
    [r] => 165
    [g] => 42
    [b] => 42
    [a] => 0
)
Normalized values:
Array
(
    [r] => 0.64705882352941
    [g] => 0.16470588235294
    [b] => 0.16470588235294
    [a] => 0.25000381475547
)

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    User Contributed Notes 1 note

    up
    3
    roman
    11 years ago
    In case you use default un-normalized getColor value the alpha value will always be either 0 or 1.

    If you want to use real full-range 0-1 alpha channel on your 24bit transparent images use the alpha value from the normalized one, even if you use the rest of unnormalized data.

    To copy a 24bit png with real alpha transparency, you would have to do this:
    <?php

    $im    =new Imagick( 'image.png' );
    $iterator=$im->getPixelIterator();
    foreach (    $iterator as $row=>$pixels) {
    foreach (     $pixels as $column => $pixel ){
    $un_color=$pixel->getColor(); //unnormalized color
    $nor_color=$pixel->getColor(true); //normalized color
    $pixel->setColor('rgba('.$un_color['r'].','.$un_color['g'].','.$un_color['b'].','.$nor_color['a'].')');
    }
    }
    ?>

    If you use 'a' (alpha) value from the unnormalized color there will only be binary transparency.
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