GD and Image 함수 목록
PHP Manual

imagecolorclosestalpha

(PHP 4 >= 4.0.6, PHP 5)

imagecolorclosestalphaGet the index of the closest color to the specified color + alpha

설명

int imagecolorclosestalpha ( resource $image , int $red , int $green , int $blue , int $alpha )

Returns the index of the color in the palette of the image which is "closest" to the specified RGB value and alpha level.

인수

image

imagecreatetruecolor() 등의 이미지 생성 함수에서 반환한 이미지 자원.

red

Value of red component.

green

Value of green component.

blue

Value of blue component.

alpha

A value between 0 and 127. 0 indicates completely opaque while 127 indicates completely transparent.

The colors parameters are integers between 0 and 255 or hexadecimals between 0x00 and 0xFF.

반환값

Returns the index of the closest color in the palette.

예제

Example #1 Search for a set of colors in an image

<?php
// Start with an image and convert it to a palette-based image
$im imagecreatefrompng('figures/imagecolorclosest.png');
imagetruecolortopalette($imfalse255);

// Search colors (RGB)
$colors = array(
    array(
25414515450),
    array(
153145188127),
    array(
153901450),
    array(
2551379284)
);

// Loop through each search and find the closest color in the palette.
// Return the search number, the search RGB and the converted RGB match
foreach($colors as $id => $rgb)
{
    
$result imagecolorclosestalpha($im$rgb[0], $rgb[1], $rgb[2], $rgb[3]);
    
$result imagecolorsforindex($im$result);
    
$result "({$result['red']}{$result['green']}{$result['blue']}{$result['alpha']})";

    echo 
"#$id: Search ($rgb[0]$rgb[1]$rgb[2]$rgb[3]); Closest match: $result.\n";
}

imagedestroy($im);
?>

위 예제의 출력 예시:

#0: Search (254, 145, 154, 50); Closest match: (252, 150, 148, 0).
#1: Search (153, 145, 188, 127); Closest match: (148, 150, 196, 0).
#2: Search (153, 90, 145, 0); Closest match: (148, 90, 156, 0).
#3: Search (255, 137, 92, 84); Closest match: (252, 150, 92, 0).

주의

Note: 이 함수는 GD 2.0.1 이상이 필요합니다. (2.0.28 이상을 권장합니다)

참고


GD and Image 함수 목록
PHP Manual