Add text watermark and text shadow to pictures in php_PHP tutorial

To add watermarks to images in PHP, we need to install the GD library for PHP. Here we will not introduce the GD library installation, but only introduce how to use PHP to add text watermarks to images and add text shadow effects.

GD library is an extension library for PHP to process graphics. The GD library provides a series of APIs for processing pictures. You can use the GD library to process pictures or generate pictures. On websites, the GD library is usually used to generate thumbnails, add watermarks to images, generate Chinese character verification codes, or generate reports on website data.

Generate renderings:

The installation of the GD library is available online, and many virtual spaces now support it, so I won’t go into details here. Below, I will introduce how to use the GD library through examples of my actual application code and related comments.

//Output $im ImageJpeg($im);

The code is as follows

代码如下

复制代码

$str="北京"; $str2= "空气质量：轻度污染"; // 通过图片生成一个对象$im $im = imagecreatefromjpeg("images/3.jpg"); //载入字体zt.ttf $fnt = "zt.ttf"; //创建颜色，用于文字字体的白和阴影的黑 $white=imagecolorallocate($im,222,229,207); $black=imagecolorallocate($im,50,50,50); //创建关于相对图片位置的函数，方便调用 $top=100; $left=60; $top2=170; //在图片中添加文字，imagettftext (image,size,angle, x, y,color,fontfile,text) imagettftext($im,41, 0, $left+1, $top+1, $black, $fnt, $str); imagettftext($im,41, 0, $left, $top, $white, $fnt, $str); imagettftext($im,43, 0, $left+1,$top2+1 , $black, $fnt, $str2); imagettftext($im,43, 0, $left,$top2, $white, $fnt, $str2); //将$im输出 ImageJpeg($im); //销毁$im对象 ImageDestroy($im);

Copy code

$str="Beijing"; $str2= "Air Quality: Mild Pollution";

// Generate an object from the image $im

$im = imagecreatefromjpeg("images/3.jpg");

代码如下	复制代码
imagettftext (image,size,angle, x, y,color,fontfile,text)

//Load font zt.ttf

$fnt = "zt.ttf";
//Create colors, white for text font and black for shadow

$white=imagecolorallocate($im,222,229,207);

$black=imagecolorallocate($im,50,50,50);

//Create a function about relative image position for easy calling

$top=100;

$left=60;

$top2=170;

//Add text to the image, imagettftext (image,size,angle, x, y,color,fontfile,text)

imagettftext($im,41, 0, $left+1, $top+1, $black, $fnt, $str);

imagettftext($im,41, 0, $left, $top, $white, $fnt, $str);

imagettftext($im,43, 0, $left+1,$top2+1 , $black, $fnt, $str2);

imagettftext($im,43, 0, $left,$top2, $white, $fnt, $str2);

//Destroy $im object ImageDestroy($im);

Let’s explain it in detail below:

The code is as follows

Copy code

imagettftext (image,size,angle, x, y,color,fontfile,text) imagettftext() draws the string text onto the image represented by image, starting from the coordinates x, y (the upper left corner is 0, 0), the angle is angle, the color is color, and the TrueType font file specified by fontfile is used. The coordinates represented by x,y define the basic point of the first character approximately at the lower left corner of the character. angle is expressed in degrees, with 0 degrees meaning the text is read from left to right and higher values ​​meaning counter-clockwise (i.e. a value of 90 means the text is read from bottom to top). fontfile is the file name of the TrueType font you want to use. text is a text string that can contain UTF-8 character sequences. color is the index value of the color. http://www.bkjia.com/PHPjc/632950.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/632950.htmlTechArticleTo add watermarks to images in php, we need to install the GD library for php. We will not introduce the GD library installation here. , only introduces how to use php to add text watermarks and text shadow effects to images. ...