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imagefilter

(PHP 5)

imagefilter — Applies a filter to an image

설명

bool imagefilter ( resource $image , int $filtertype [, int $arg1 [, int $arg2 [, int $arg3 [, int $arg4 ]]]] )

imagefilter() applies the given filter filtertype on the image .

매개변수

font

내장 글꼴 1, 2, 3, 4, 5(큰 숫자가 큰 글꼴)나 imageloadfont()로 등록한 글꼴 식별자를 사용할 수 있습니다.

filtertype

filtertype can be one of the following:

  • IMG_FILTER_NEGATE: Reverses all colors of the image.
  • IMG_FILTER_GRAYSCALE: Converts the image into grayscale.
  • IMG_FILTER_BRIGHTNESS: Changes the brightness of the image. Use arg1 to set the level of brightness.
  • IMG_FILTER_CONTRAST: Changes the contrast of the image. Use arg1 to set the level of contrast.
  • IMG_FILTER_COLORIZE: Like IMG_FILTER_GRAYSCALE, except you can specify the color. Use arg1 , arg2 and arg3 in the form of red , blue , green and arg4 for the alpha channel. The range for each color is 0 to 255.
  • IMG_FILTER_EDGEDETECT: Uses edge detection to highlight the edges in the image.
  • IMG_FILTER_EMBOSS: Embosses the image.
  • IMG_FILTER_GAUSSIAN_BLUR: Blurs the image using the Gaussian method.
  • IMG_FILTER_SELECTIVE_BLUR: Blurs the image.
  • IMG_FILTER_MEAN_REMOVAL: Uses mean removal to achieve a "sketchy" effect.
  • IMG_FILTER_SMOOTH: Makes the image smoother. Use arg1 to set the level of smoothness.

arg1

arg2

arg3

반환값

성공할 경우 TRUE를, 실패할 경우 FALSE를 반환합니다.

변경 기록

버전 설명
5.2.5 Alpha support for IMG_FILTER_COLORIZE was added.

예제

Example#1 imagefilter() grayscale example

<?php
$im 
imagecreatefrompng('dave.png');
if (
$im && imagefilter($imIMG_FILTER_GRAYSCALE)) {
    echo 
'Image converted to grayscale.';
    
imagepng($im'dave.png');
} else {
    echo 
'Conversion to grayscale failed.';
}

imagedestroy($im);
?>

Example#2 imagefilter() brightness example

<?php
$im 
imagecreatefrompng('sean.png');
if (
$im && imagefilter($imIMG_FILTER_BRIGHTNESS20)) {
    echo 
'Image brightness changed.';
    
imagepng($im'sean.png');
} else {
    echo 
'Image brightness change failed.';
}

imagedestroy($im);
?>

Example#3 imagefilter() colorize example

<?php
$im 
imagecreatefrompng('philip.png');

/* R, G, B, so 0, 255, 0 is green */
if ($im && imagefilter($imIMG_FILTER_COLORIZE02550)) {
    echo 
'Image successfully shaded green.';
    
imagepng($im'philip.png');
} else {
    echo 
'Green shading failed.';
}

imagedestroy($im);
?>

주의

Note: 이 함수는 PHP에 포함된 GD 라이브러리를 사용하여 컴파일하였을 경우에만 사용할 수 있습니다.


08, Erik Sefkow