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PHP implements the inverse color processing function of images php skills

jacklove

Release： 2023-04-01 22:34:01

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This article mainly introduces the function of inverse color processing of images in PHP, involving PHP's related operation skills for image reading, numerical calculations, etc. Friends in need can refer to the following

The examples in this article are described PHP implements the function of inverting the color of images. I share it with you for your reference. The details are as follows:

Today I have a need to use php to invert the color of the image and turn it gray. I didn’t know if it was possible before, but then I saw imagefilter() The function is more than enough to turn gray, so powerful;

imagefilter($im, IMG_FILTER_GRAYSCALE)

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Of course, some people also set gray in css

<style type="text/css">
img {
-webkit-filter: grayscale(1);/* Webkit */
filter:gray;/* IE6-9 */
filter: grayscale(1);/* W3C */
}
</style>

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php color transfer code:

<?php
/**
* 主要用于图片的处理函数
*/
//图片的反色功能
function color($url) {
  //获取图片的信息
  　　list($width, $height, $type, $attr)= getimagesize($url);
  　　$imagetype = strtolower(image_type_to_extension($type,false));
  　　$fun = &#39;imagecreatefrom&#39;.($imagetype == &#39;jpg&#39;?&#39;jpeg&#39;:$imagetype);
  　　$img = $fun($url);
  　　for ($y=0; $y < $height; $y++) {
    　　for ($x=0; $x <$width; $x++) {
    　　　　//获取颜色的所以值
    　　　　$index = imagecolorat($img, $x, $y);
    　　　　//获取颜色的数组
    　　　　$color = imagecolorsforindex($img, $index);
    　　　　//颜色值的反转
    　　　　$red = 256 - $color[&#39;red&#39;];
    　　　　$green = 256 - $color[&#39;green&#39;];
    　　　　$blue = 256 - $color[&#39;blue&#39;];
    　　　　$hex = imagecolorallocate($img, $red, $green, $blue);
    　　　　//给每一个像素分配颜色值
    　　　　imagesetpixel($img, $x, $y, $hex);
  　　　　}
  　　}
  　　//输出图片
  　　switch ($imagetype) {
    　　case &#39;gif&#39;:
    　　imagegif($img);
    　　break;
  　　　　case &#39;jpeg&#39;:
    　　imagejpeg($img);
    　　break;
  　　　　case &#39;png&#39;:
    　　imagepng($img);
    　　break;
  　　　　default:
    　　break;
  　　}
}

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Test code:

$imgurl=&#39;1.jpg&#39;;
echo color($imgurl);

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Original picture (take this childhood-ruining spoof picture commonly used by the editor as an example):

Run Finally (this is mainly for testing. As for whether the picture subverts the three views or the five senses, the editor will not ask too much~):

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