How to add watermark to php images

How to add watermark to php pictures: 1. Set text watermark through "waterText('banner.jpg', 9, '','xx.com');"; 2. Through "imageWaterMark('404 .jpg', 9, 'logo.gif');"Set image watermark.

#The operating environment of this article: Windows 7 system, PHP version 7.1, Dell G3 computer.

Examples of adding image watermarks and text watermarks to images with PHP

Let me share with you an example of adding image watermarks and text watermarks to images with PHP. This is also a function often used by websites. Once the code is added, the call is very simple.

Core code:

function imageWaterMark($groundImage, $waterPos = 0, $waterImage = "", $waterText = "", $textFont = 5, $textColor = "#FF0000") {

    $isWaterImage = FALSE;

    $formatMsg = "暂不支持该文件格式，请用图片处理软件将图片转换为GIF、JPG、PNG格式。";

    //读取水印文件

    if (!empty($waterImage) && file_exists($waterImage)) {

        $isWaterImage = TRUE;

        $water_info = getimagesize($waterImage);

        $water_w = $water_info[0]; //取得水印图片的宽

        $water_h = $water_info[1]; //取得水印图片的高

        switch ($water_info[2]) {//取得水印图片的格式
            case 1:$water_im = imagecreatefromgif($waterImage);
                break;

            case 2:$water_im = imagecreatefromjpeg($waterImage);
                break;

            case 3:$water_im = imagecreatefrompng($waterImage);
                break;

            default:die($formatMsg);
        }
    }

    //读取背景图片

    if (!empty($groundImage) && file_exists($groundImage)) {

        $ground_info = getimagesize($groundImage);

        $ground_w = $ground_info[0]; //取得背景图片的宽

        $ground_h = $ground_info[1]; //取得背景图片的高

        switch ($ground_info[2]) {//取得背景图片的格式
            case 1:$ground_im = imagecreatefromgif($groundImage);
                break;

            case 2:$ground_im = imagecreatefromjpeg($groundImage);
                break;

            case 3:$ground_im = imagecreatefrompng($groundImage);
                break;

            default:die($formatMsg);
        }
    } else {

        die("需要加水印的图片不存在！");
    }

    //水印位置

    if ($isWaterImage) {//图片水印
        $w = $water_w;

        $h = $water_h;

        $label = "图片的";
    } else {//文字水印
        $temp = imagettfbbox(ceil($textFont * 5), 0, "./cour.ttf", $waterText); //取得使用 TrueType 字体的文本的范围

        $w = $temp[2] - $temp[6];

        $h = $temp[3] - $temp[7];

        unset($temp);

        $label = "文字区域";
    }

    if (($ground_w < $w) || ($ground_h < $h)) {

        echo "需要加水印的图片的长度或宽度比水印" . $label . "还小，无法生成水印！";

        return;
    }

    switch ($waterPos) {

        case 0://随机

            $posX = rand(0, ($ground_w - $w));

            $posY = rand(0, ($ground_h - $h));

            break;

        case 1://1为顶端居左

            $posX = 0;

            $posY = 0;

            break;

        case 2://2为顶端居中

            $posX = ($ground_w - $w) / 2;

            $posY = 0;

            break;

        case 3://3为顶端居右

            $posX = $ground_w - $w;

            $posY = 0;

            break;

        case 4://4为中部居左

            $posX = 0;

            $posY = ($ground_h - $h) / 2;

            break;

        case 5://5为中部居中

            $posX = ($ground_w - $w) / 2;

            $posY = ($ground_h - $h) / 2;

            break;

        case 6://6为中部居右

            $posX = $ground_w - $w;

            $posY = ($ground_h - $h) / 2;

            break;

        case 7://7为底端居左

            $posX = 0;

            $posY = $ground_h - $h;

            break;

        case 8://8为底端居中

            $posX = ($ground_w - $w) / 2;

            $posY = $ground_h - $h;

            break;

        case 9://9为底端居右

            $posX = $ground_w - $w - 10;   // -10 是距离右侧10px 可以自己调节

            $posY = $ground_h - $h - 10;   // -10 是距离底部10px 可以自己调节

            break;

        default://随机

            $posX = rand(0, ($ground_w - $w));

            $posY = rand(0, ($ground_h - $h));

            break;
    }

    //设定图像的混色模式

    imagealphablending($ground_im, true);

    if ($isWaterImage) {//图片水印
        imagecopy($ground_im, $water_im, $posX, $posY, 0, 0, $water_w, $water_h); //拷贝水印到目标文件
    } else {//文字水印
        if (!emptyempty($textColor) && (strlen($textColor) == 7)) {

            $R = hexdec(substr($textColor, 1, 2));

            $G = hexdec(substr($textColor, 3, 2));

            $B = hexdec(substr($textColor, 5));
        } else {

            die("水印文字颜色格式不正确！");
        }

        imagestring($ground_im, $textFont, $posX, $posY, $waterText, imagecolorallocate($ground_im, $R, $G, $B));
    }

    //生成水印后的图片

    @unlink($groundImage);

    switch ($ground_info[2]) {//取得背景图片的格式
        case 1:imagegif($ground_im, $groundImage);
            break;

        case 2:imagejpeg($ground_im, $groundImage);
            break;

        case 3:imagepng($ground_im, $groundImage);
            break;

        default:die($errorMsg);
    }

    //释放内存

    if (isset($water_info))
        unset($water_info);

    if (isset($water_im))
        imagedestroy($water_im);

    unset($ground_info);

    imagedestroy($ground_im);
}

Text watermark:

waterText('banner.jpg', 9, '','sucaihuo.com'); //背景图片,$waterPos水印位置,水印图片地址

Image watermark:

imageWaterMark('404.jpg', 9, 'logo.gif'); //背景图片,$waterPos水印位置,水印图片地址

Note: It is best not to use $waterImage and $waterText at the same time. Select One of them will do, and $waterImage will be used first.

Recommended learning: "PHP Video Tutorial"

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