GD library function to implement Chinese watermark_PHP tutorial

　$im = imagecreatetruecolor(100,100);//Create a new true color image

　$white = imagecolorallocate($im,255,235,255);//Assigning a color to an image is different from my design common sense. I have never thought that when painting, I must first assign a specified image Logo assigns color. This function is often confused with the imagefill function.

Imagefill($im,0,0,$white); //Area filling

　$black = imagecolorallocate($im,250,50,50);//Assign a color to an image

Imagerectangle($im,5,5,50,50,$black);//Draw a rectangle

Header("Content-type: image/jpeg"); //Send the header and output the image directly in the browser with imagejpeg.

Imagejpeg($im,ImageName,100);//Output an image, name and quality

Imagedestroy($im);//Release the memory associated with image. image is the image identifier returned by the image creation function

　?>

Use GD library to implement "Chinese watermark"

Publish time: 2006-12-29 20:50 Author: hy0kl Source: PHPChina Open Source Community Portal

First of all, I would like to express my special thanks to lmhllr, my friend. Without his guidance, I might still be searching for information...

First of all, I would like to state that I am a newbie and have little knowledge of the GD library. Please forgive me for any shortcomings. ^_^

Since I saw on the Internet that php + GD library can add "Chinese watermark" to images, I started to learn the GD library.

So I modified a script based on the downloaded information, which can realize PHP drawing. I was very happy for a long time. (Laughing!)

Then I used the imagestring() function to implement an English "watermark" on the image; but when I tried to use it to add a "Chinese watermark", all that was printed was garbled.

So I started on the road to solve the garbled code again.

I gave up after not getting a satisfactory answer for a long time.

Recently, I discovered that lmhllr’s personalized signature is very special. After asking, I finally found out the reason: the GD library does not support Chinese very well. If the character set of the imagettftext() function is UTF-8, it can be passed directly.

In other words, the character set of gb2312 must be converted into UTF-8 characters. You can use the iconv() function to achieve this. I can’t find this function in the collector’s edition PHP manual, but you can go to the official PHP website to view http ://cn.php.net/manual/zh/ref.iconv.php, but unfortunately not all functions have Chinese translations. My E language is not good, so I can only guess by looking at the example script of lmhllr. This is The function converts gb2312 characters into UTF-8 characters. Then the function is called to add "Chinese watermark".

After testing on my machine, I found that the Chinese fonts supported by GD include simhei.ttf (Heoldbody), SIMKAI.TTF (Kaili), SIMFANG.TTF (Imitation Song Dynasty), SIMSUN.TTC (Song Dynasty & New Song Dynasty), etc. Of course, only English names can be substituted into the script. Hey, we didn’t write the operating system.

I hope this post can give some inspiration to comrades who have experienced the same thing as me. ^_^

The following is a simple test script.

　[php]

Header("Content-type: image/png"); /*Notify the browser to output an image*/

　$im = imagecreate(400, 300); /*Define the size of the image*/

　$gray = ImageColorAllocate($im, 235, 235, 235);

　$pink = ImageColorAllocate($im, 255, 128, 255);

　/*

　$fontfile = "C:WINDOWSFontsSIMHEI.TTF";

Sorry, this sentence is always lost after being pasted and submitted. I don’t know what happened. Friends who want to test it, please leave the comment and test it now

　*/

　/*$fontfile The path of the font, depending on the operating system, can be simhei.ttf (Helvetica), SIMKAI.TTF (Italian), SIMFANG.TTF (Imitation Song Dynasty), SIMSUN.TTC (Song Dynasty & New Song Dynasty), etc. Chinese fonts supported by GD*/

　$str = iconv(GB2312,UTF-8,Chinese watermark!!!); /*Convert gb2312 character set to UTF-8 characters*/

ImageTTFText($im, 30, 0, 50, 140, $pink, $fontfile, $str);

　/* Add Chinese watermark */

Imagepng($im);

ImageDestroy($im);

　?>[/php]

OK, call it a day, I hope this is my first quality post.

The following is the effect of this example. I would like to express my sincere thanks to lmhllr again!!!