PHP轮子之图片局部马赛克

1<?php
2class Mosaic {
3    public function run() {
4        $filename     = './image.jpg'; // 要被打马赛克的图片路径
5        $saveFileName = './image_mosaic.jpg';// 打上马赛克后的保存名
6        $x            = 200; // 起始位置的x
7        $y            = 20; // 起始位置的y
8        $width        = 100; // 马赛克区域的宽度
9        $height       = 30; // 马赛克区域的高度
10        list($src_w) = getimagesize($filename); // 原图片的宽度
11        $image = imagecreatefromjpeg($filename);
12        $deep  = $this->getDeep($src_w);
13        for ($i = 0; $i < $width; $i += $deep) {
14            for ($j = 0; $j < $height; $j += $deep) {
15                $calcX = $x + $i;
16                $calcY = $y + $j;
17                $color = imagecolorat($image, $calcX + round($deep / 2), $calcY + round($deep / 2));
18                $rgb   = $this->getColor($color);
19                $col   = imagecolorallocatealpha($image, $rgb['r'], $rgb['g'], $rgb['b'], 0);
20                imagefilledrectangle($image, $calcX, $calcY, $calcX + $deep, $calcY + $deep, $col);
21            }
22        }
23        imagejpeg($image, $saveFileName);
24        imagedestroy($image);
25    }
26
27    /**
28     * 获取颜色RGBA
29     *
30     * @param int $rgb 颜色值
31     *
32     * @return array
33     */
34    protected function getColor(int $rgb) {
35        $rColorNum = $gColorNum = $bColorNum = $total = 0;
36        //三通道
37        $r         = ($rgb >> 16) & 0xFF;
38        $g         = ($rgb >> 8) & 0xFF;
39        $b         = $rgb & 0xFF;
40        $rColorNum += $r;
41        $gColorNum += $g;
42        $bColorNum += $b;
43        $total++;
44        $rgb      = [];
45        $rgb['r'] = round($rColorNum / $total);
46        $rgb['g'] = round($gColorNum / $total);
47        $rgb['b'] = round($bColorNum / $total);
48        // 替换比较黑的颜色值，让比较黑的颜色变淡
49        $cover = 104; // 替换为#686868
50        foreach ($rgb as $key => &$value) {
51            if ($value < $cover) {
52                $value = $cover;
53            }
54        }
55
56        return $rgb;
57    }
58
59    /**
60     * 根据图片长度计算马赛克框大小
61     *
62     * @param int $width 图片的长度
63     *
64     * @return int
65     */
66    protected function getDeep(int $width) {
67        switch (true) {
68            case $width >= 3000 :
69                return 30;
70            case $width >= 2000 :
71                return 20;
72            case $width >= 1000 :
73                return 10;
74            case $width >= 100 :
75                return 5;
76        }
77    }
78}
79$mosaic = new Mosaic();
80$mosaic->run();