PHP GD库 生成图片水印

* index.php

<?php
/**
 * Created by PhpStorm.
 * User: mingzhanghui
 * Date: 9/24/2019
 * Time: 12:47
 */

include "autoload.php";


// 头像图片
$dstPath = dirname(__FILE__)."/image/avatar.jpg";
// 国旗图片
$srcPath = dirname(__FILE__)."/image/flag.png";

/** @var $dataDst string image content */
$dataDst = file_get_contents($dstPath);
$dataSrc = file_get_contents($srcPath);
$dst = imagecreatefromstring($dataDst);
list($dstW, $dstH) = getimagesize($dstPath);

list($srcW, $srcH) = getimagesize($srcPath);
// 宽度是小图的3倍
$thumbWidth = 3 * $srcW;
$thumbHeight = $thumbWidth * ($dstH/$dstW);
$data = \lib\Image::resize($dataDst, $thumbWidth, $thumbHeight, 0);
if (!$data) {
    echo "resize failed\n";
    exit(1);
}
$dst = imagecreatefromstring($data);
$info = getimagesize($dstPath);
// 'mime' => 'image/jpeg'
// 'mime' => 'image/png'

$a = explode('/', $info['mime']);
$type = array_pop($a);
unset($a);

$dstPath = "tmp.".$type;
call_user_func("image".$type, $dst, $dstPath);
// == 缩略图生成完了 ==

$dstW = $thumbWidth;
$dstH = $thumbHeight;
list($dstW, $dstH) = getimagesize($dstPath);

$src = imagecreatefromstring($dataSrc);

imagecopymerge($dst, $src,
    $dstW - $srcW, $dstH - $srcH,
    0, 0, $srcW, $srcH, 100);

/*
header("Content-Type: ".$info['mime']);
// imagepng();
call_user_func("image".$type, $dst);
*/

call_user_func("image".$type, $dst, "out.".$type);

imagedestroy($src);
imagedestroy($dst);

* autoload.php

<?php
/**
 * Created by PhpStorm.
 * User: mingzhanghui
 * Date: 9/24/2019
 * Time: 13:16
 */

$prefixList = ['lib'];

$pwd = dirname(__FILE__);

foreach ($prefixList as $prefix) {
    spl_autoload_register(function($class) use ($prefix, $pwd) {
        $base_dir = $pwd . DIRECTORY_SEPARATOR. str_replace('\\', '/', $prefix);
        // echo $base_dir.PHP_EOL;
        $len = strlen($prefix);
        if (strncmp($prefix, $class, $len) !== 0) {
            return;
        }
        $relative_class = substr($class, $len);
        $file = $base_dir . str_replace('\\', '/', $relative_class) . '.php';
        // echo $file.PHP_EOL;
        if (file_exists($file)) {
            require $file;
        }
    });
}

* ./lib/Image.php

<?php
/**
 * Created by PhpStorm.
 * User: mingzhanghui
 * Date: 9/24/2019
 * Time: 13:15
 */

namespace lib;

class Image
{
    /**
     * @param $imagedata  string  图像数据
     * @param $width    int    缩放宽度
     * @param $height    int   缩放高度
     * @param int $per     缩放比例，为0不缩放，>0忽略参数2、3的宽高
     * @return bool|string
     */
    public static function resize($imagedata, $width, $height, $per = 0) {
        // 1 = GIF，2 = JPG，3 = PNG，4 = SWF，5 = PSD，6 = BMP，7 = TIFF(intel byte order)，8 = TIFF(motorola byte order)，9 = JPC，10 = JP2，11 = JPX，12 = JB2，13 = SWC，14 = IFF，15 = WBMP，16 = XBM
        // 获取图像信息
        list($bigWidth, $bigHight, $bigType) = getimagesizefromstring($imagedata);

        // 缩放比例
        if ($per > 0) {
            $width  = $bigWidth * $per;
            $height = $bigHight * $per;
        }

        // 创建缩略图画板
        $block = imagecreatetruecolor($width, $height);

        // 启用混色模式
        imagealphablending($block, false);

        // 保存PNG alpha通道信息
        imagesavealpha($block, true);

        // 创建原图画板
        $bigImg = imagecreatefromstring($imagedata);

        // 缩放
        imagecopyresampled($block, $bigImg, 0, 0, 0, 0,
            $width, $height, $bigWidth, $bigHight);

        // 生成临时文件名
        $tmpFilename = tempnam(sys_get_temp_dir(), 'image_');

        // 保存
        switch ($bigType) {
            case 1: imagegif($block, $tmpFilename);
                break;

            case 2: imagejpeg($block, $tmpFilename);
                break;

            case 3: imagepng($block, $tmpFilename);
                break;
        }

        // 销毁
        imagedestroy($block);

        $image = file_get_contents($tmpFilename);

        unlink($tmpFilename);

        return $image;
    }
}

 

把国旗图片覆盖到目的图片右下角