Home Backend Development PHP Tutorial Generate image thumbnails in batches with PHP

Generate image thumbnails in batches with PHP

Jul 25, 2016 am 08:44 AM

  1. function mkdirs($dirname,$mode=0777) //Create directory (directory, [mode])
  2. {
  3. if(!is_dir($ dirname))
  4. {
  5. mkdirs($dirname,$mode); //If the directory does not exist, create it recursively
  6. return mkdir($dirname,$mode);
  7. }
  8. return true;
  9. }
  10. function savefile($filename ,$content='') //Save file(file, [content])
  11. {
  12. if(function_exists(file_put_contents))
  13. {
  14. file_put_contents($filename,$content);
  15. }
  16. else
  17. {
  18. $fp= fopen($filename,"wb");
  19. fwrite($fp,$content);
  20. fclose($fp);
  21. }
  22. }
  23. function getsuffix($filename) //Get the file name suffix
  24. {
  25. return end (explode(".",$filename));
  26. }
  27. function checksuffix($filename,$arr) //Whether it is an allowed type (current, allowed)
  28. {
  29. if(!is_array($arr))
  30. {
  31. $arr=explode(",",str_replace(" ","",$arr));
  32. }
  33. return in_array($filename,$arr) ? 1 : 0;
  34. }
  35. class image
  36. {
  37. var $src; //Source address
  38. var $newsrc; //New picture path (after localization)
  39. var $allowtype=array(".gif",".jpg",".png",".jpeg"); //Allowed image types
  40. var $regif=0; //Whether to abbreviate GIF, if it is 0, it will not be processed
  41. var $keep=0; //Whether to keep the source file (1 means to keep, 0 means MD5)
  42. var $over =0; //Whether the existing picture can be overwritten, if it is 0, it cannot be overwritten
  43. var $dir; //Picture source directory
  44. var $newdir; //Processed directory
  45. function __construct($olddir=null,$ newdir=null)
  46. {
  47. $this->dir=$olddir ? $olddir : "./images/temp";
  48. $this->newdir=$newdir ? $newdir : "./images/s";
  49. }
  50. function reNames($src)
  51. {
  52. $md5file=substr(md5($src),10,10).strrchr($src,"."); //After the MD5 file name (for example: 3293okoe. gif)
  53. $md5file=$this->w."_".$this->h."_".$md5file; //Processed file name
  54. return $this->newdir."/". $md5file; //Save the source image and MD5 file name to a new directory
  55. }
  56. function Mini($src,$w,$h,$q=80) //Generate thumbnail Mini(picture address, width, height, quality)
  57. {
  58. $this->src=$src;
  59. $this->w=$w;
  60. $this->h=$h;
  61. if(strrchr($src," .")==".gif" && $this->regif==0) //Whether to process GIF images
  62. {
  63. return $this->src;
  64. }
  65. if($this->keep== 0) //Whether to retain the source file, not retained by default
  66. {
  67. $newsrc=$this->reNames($src); //Renamed file address
  68. }
  69. else //Keep the original name
  70. {
  71. $src= str_replace("\","/",$src);
  72. $newsrc=$this->newdir.strrchr($src,"/");
  73. }
  74. if(file_exists($newsrc) && $this-> ;over==0) //If it already exists, return the address directly
  75. {
  76. return $newsrc;
  77. }
  78. if(strstr($src,"http://") && !strstr($src,$_SERVER[' HTTP_HOST']))//If it is a network file, save it first
  79. {
  80. $src=$this->getimg($src);
  81. }
  82. $arr=getimagesize($src); //Get image attributes
  83. $ width=$arr[0];
  84. $height=$arr[1];
  85. $type=$arr[2];
  86. switch($type)
  87. {
  88. case 1: //1 = GIF,
  89. $im= imagecreatefromgif($src);
  90. break;
  91. case 2: //2 = JPG
  92. $im=imagecreatefromjpeg($src);
  93. break;
  94. case 3: //3 = PNG
  95. $im=imagecreatefrompng($src);
  96. break;
  97. default:
  98. return 0;
  99. }
  100. //Process thumbnails
  101. $nim=imagecreatetruecolor($w,$h);
  102. $k1=round($h/$w,2);
  103. $k2 =round($height/$width,2);
  104. if($k1<$k2)
  105. {
  106. $width_a=$width;
  107. $height_a=round($width*$k1);
  108. $sw=0;
  109. $sh=($height-$height_a)/2;
  110. }
  111. else
  112. {
  113. $width_a=$height/$k1;
  114. $height_a=$height;
  115. $sw=($width-$width_a)/2;
  116. $sh = 0;
  117. }
  118. //生成图片
  119. if(function_exists(imagecopyresampled))
  120. {
  121. imagecopyresampled($nim,$im,0,0,$sw,$sh,$w,$h,$width_a,$height_a);
  122. }
  123. else
  124. {
  125. imagecopyresized($nim,$im,0,0,$sw,$sh,$w,$h,$width_a,$height_a);
  126. }
  127. if(!is_dir($this->newdir))
  128. {
  129. mkdir($this->newdir);
  130. }
  131. switch($type) //保存图片
  132. {
  133. case 1:
  134. $rs=imagegif($nim,$newsrc);
  135. break;
  136. case 2:
  137. $rs=imagejpeg($nim,$newsrc,$q);
  138. break;
  139. case 3:
  140. $rs=imagepng($nim,$newsrc);
  141. break;
  142. default:
  143. return 0;
  144. }
  145. return $newsrc; //返回处理后路径
  146. }
  147. function getimg($filename)
  148. {
  149. $md5file=$this->dir."/".substr(md5($filename),10,10).strrchr($filename,".");
  150. if(file_exists($md5file))
  151. {
  152. return $md5file;
  153. }
  154. //开始获取文件,并返回新路径
  155. $img=file_get_contents($filename);
  156. if($img)
  157. {
  158. if(!is_dir($this->dir))
  159. {
  160. mkdir($this->dir);
  161. }
  162. savefile($md5file,$img);
  163. return $md5file;
  164. }
  165. }
  166. function reImg($src,$w,$h,$q) //转换缩略图(文件名和结构不变)
  167. {
  168. $this->keep=1;
  169. return $this->Mini($src,$w,$h,$q); //return 生成的地址
  170. }
  171. }
  172. $image=new image();
  173. echo $image->reImg("images/zht.jpg",75,75,80);
  174. echo "
    ";
  175. echo $image->reImg("images/m8920.jpg",75,75,80);
  176. echo "
    ";
  177. echo $image->getimg("./images/s/zht.jpg");
  178. ?>
复制代码

PHP


Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

How does session hijacking work and how can you mitigate it in PHP? How does session hijacking work and how can you mitigate it in PHP? Apr 06, 2025 am 12:02 AM

Session hijacking can be achieved through the following steps: 1. Obtain the session ID, 2. Use the session ID, 3. Keep the session active. The methods to prevent session hijacking in PHP include: 1. Use the session_regenerate_id() function to regenerate the session ID, 2. Store session data through the database, 3. Ensure that all session data is transmitted through HTTPS.

Describe the SOLID principles and how they apply to PHP development. Describe the SOLID principles and how they apply to PHP development. Apr 03, 2025 am 12:04 AM

The application of SOLID principle in PHP development includes: 1. Single responsibility principle (SRP): Each class is responsible for only one function. 2. Open and close principle (OCP): Changes are achieved through extension rather than modification. 3. Lisch's Substitution Principle (LSP): Subclasses can replace base classes without affecting program accuracy. 4. Interface isolation principle (ISP): Use fine-grained interfaces to avoid dependencies and unused methods. 5. Dependency inversion principle (DIP): High and low-level modules rely on abstraction and are implemented through dependency injection.

What are Enumerations (Enums) in PHP 8.1? What are Enumerations (Enums) in PHP 8.1? Apr 03, 2025 am 12:05 AM

The enumeration function in PHP8.1 enhances the clarity and type safety of the code by defining named constants. 1) Enumerations can be integers, strings or objects, improving code readability and type safety. 2) Enumeration is based on class and supports object-oriented features such as traversal and reflection. 3) Enumeration can be used for comparison and assignment to ensure type safety. 4) Enumeration supports adding methods to implement complex logic. 5) Strict type checking and error handling can avoid common errors. 6) Enumeration reduces magic value and improves maintainability, but pay attention to performance optimization.

How to debug CLI mode in PHPStorm? How to debug CLI mode in PHPStorm? Apr 01, 2025 pm 02:57 PM

How to debug CLI mode in PHPStorm? When developing with PHPStorm, sometimes we need to debug PHP in command line interface (CLI) mode...

How to automatically set permissions of unixsocket after system restart? How to automatically set permissions of unixsocket after system restart? Mar 31, 2025 pm 11:54 PM

How to automatically set the permissions of unixsocket after the system restarts. Every time the system restarts, we need to execute the following command to modify the permissions of unixsocket: sudo...

Explain late static binding in PHP (static::). Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

See all articles