PHP 5.5.16 is released

imagecolorresolve

(PHP 4, PHP 5)

imagecolorresolveGet the index of the specified color or its closest possible alternative

Descrierea

int imagecolorresolve ( resource $image , int $red , int $green , int $blue )

This function is guaranteed to return a color index for a requested color, either the exact color or the closest possible alternative.

Dacă ați creat imaginea din fișier atunci sunt determinate doar culorile utilizate în imagine. Culorile prezente doar în paletă nu sunt determinate.

Parametri

image

O resursă - imagine, întoarsă de una din funcțiile de creare a imaginilor, cum ar fi imagecreatetruecolor().

red

Valoarea componentei roșii.

green

Valoarea componentei verzi.

blue

Valoarea componentei albastre.

Valorile întoarse

Returns a color index.

Exemple

Example #1 Using imagecoloresolve() to get colors from an image

<?php
// Load an image
$im imagecreatefromgif('phplogo.gif');

// Get closest colors from the image
$colors = array();
$colors[] = imagecolorresolve($im255255255);
$colors[] = imagecolorresolve($im00200);

// Output
print_r($colors);

imagedestroy($im);
?>

Exemplul de mai sus va afișa ceva similar cu:

Array
(
    [0] => 89
    [1] => 85
)

Vedeți de asemenea

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User Contributed Notes 1 note

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ceo at l-i-e dot com
12 years ago
Okay, so sometimes it's really IMPORTANT to get the exact color you want, only it's not *IN* the Image, and ImageColorResolve just isn't "close enough".

The following code is a disgustingly gross hack, rather slow, but it does that.

$colorcount = array();
for ($x = 0; $x < $width; $x++){
    for ($y = 0; $y < $height; $y++){
        $colorindex = imagecolorat($jpg, $x, $y);
        if (!isset($colorcount[$colorindex])){
            $colorcount[$colorindex] = 1;
        }
        else{
            $colorcount[$colorindex]++;
        }
    }
}
asort($colorcount);
reset($colorcount);

$black = imagecolorexact($jpg, 0, 0, 0);
if ($black == -1){
    $goner = key($colorcount);
    $rgb = imagecolorsforindex($jpg, $goner);
    #error_log("Need black: About to kill $goner ($rgb[red], $rgb[green], $rgb[blue]) which was only used in $colorcount[$goner] pixels", 0);
    unset($colorcount[$goner]);
    imagecolordeallocate($jpg, $goner);
    $black = imagecolorallocate($jpg, 0, 0, 0);
}
if ($black == -1){
    $black = imagecolorresolve($jpg, 0, 0, 0);
    #error_log("Damn!  STILL couldn't allocate the color!", 0);
}
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