initial release

CImage.php

@@ -0,0 +1,273 @@
+<?php
+/**
+ * Resizing images on the fly.
+ *
+ * @author Mikael Roos mos@dbwebb.se
+ * @example http://dbwebb.se/example/lessphp/
+ * @link https://github.com/mosbth/Utility/blob/master/style.php
+ */
+class CImage {
+
+  /**
+   * Properties
+   */
+  private $image = null; // Object for open image
+  public $pathToImage;
+  private $fileExtension;
+  public $newWidth;
+  public $newHeight;
+  private $cropWidth;
+  private $cropHeight;
+  public $keepRatio;
+  public $crop;
+  public $saveFolder;
+  public $newName;
+  private $newFileName;
+  private $mime; // Calculated from source image
+  private $width; // Calculated from source image
+  private $height; // Calculated from source image
+  private $type; // Calculated from source image
+  private $attr; // Calculated from source image
+  private $validExtensions = array('jpg', 'jpeg', 'png', 'gif');
+
+
+  /**
+   * Constructor, can take arguments to init the object.
+   *
+   * @param $pathToImage string the filepath to the image.
+   * @param $newWidth integer the new width or null.
+   * @param $newHeight integer the new width or null.
+   * @param $keepRatio boolean true to keep aspect ratio else false.
+   * @param $saveFolder string path to folder where to save the new file or null to skip saving.
+   * @param $newName string new filename or leave to null to autogenerate filename.
+   */
+  public function __construct($pathToImage=null, $newWidth=null, $newHeight=null, 
+                              $keepRatio=true, $crop=false, $saveFolder=null, $newName=null) {
+    $this->pathToImage = $pathToImage;
+    $this->fileExtension = pathinfo($this->pathToImage, PATHINFO_EXTENSION);
+    $this->newWidth = $newWidth;
+    $this->newHeight = $newHeight;
+    $this->keepRatio = $keepRatio;
+    $this->crop = $crop;
+    $this->saveFolder = $saveFolder;
+    $this->newName = $newName;
+  }
+
+
+  /**
+   * Raise error, enables to implement a selection of error methods.
+   *
+   * @param $message string the error message to display.
+   */
+  public function RaiseError($message) {
+    throw new Exception($message);
+  }
+  
+  
+  /**
+   * Create filename to save file in cache.
+   */
+  public function CreateFilename() {
+    $parts = pathinfo($this->pathToImage);
+    $crop = $this->crop ? '_c_' : null;
+    return $this->saveFolder . '/' . $parts['filename'] . '_' . round($this->newWidth) . '_' . round($this->newHeight) . $crop . '.' . $parts['extension'];
+  }
+  
+  
+  /**
+   * Init and do some sanity checks before any processing is done. Throws exception if not valid.
+   */
+  public function Init() {
+    is_null($this->newWidth) or is_numeric($this->newWidth) or $this->RaiseError('Width not numeric');
+    is_null($this->newHeight) or is_numeric($this->newHeight) or $this->RaiseError('Height not numeric');
+    is_readable($this->pathToImage) or $this->RaiseError('File does not exist.');
+    in_array($this->fileExtension, $this->validExtensions) or $this->RaiseError('Not a valid file extension.');
+    is_null($this->saveFolder) or is_writable($this->saveFolder) or $this->RaiseError('Save directory does not exist or is not writable.');
+
+    // Get details on image
+    $info = list($this->width, $this->height, $this->type, $this->attr) = getimagesize($this->pathToImage);
+    !empty($info) or $this->RaiseError("The file doesn't seem to be an image.");
+    $this->mime = $info['mime'];
+
+    return $this;
+  }
+  
+
+  /**
+   * Output image using caching.
+   *
+   */
+  protected function Output($file) {
+    $time = filemtime($file);  
+    if(isset($_SERVER['If-Modified-Since']) && strtotime($_SERVER['If-Modified-Since']) >= $time){  
+      header("HTTP/1.0 304 Not Modified");
+    } else {  
+      header('Content-type: ' . $this->mime);  
+      header('Last-Modified: ' . gmdate("D, d M Y H:i:s",$time) . " GMT");  
+      readfile($file);
+    }
+    exit;
+  }
+  
+ 
+  /**
+   * Open image.
+   *
+   */
+  protected function Open() {
+    switch($this->fileExtension) {  
+      case 'jpg':
+      case 'jpeg': $this->image = @imagecreatefromjpeg($this->pathToImage); break;  
+      case 'gif':  $this->image = @imagecreatefromgif($this->pathToImage); break;  
+      case 'png':  $this->image = @imagecreatefrompng($this->pathToImage); break;  
+      default: $this->image = false; $this->RaiseError('No support for this file extension.');
+    }
+    return $this;
+  }
+  
+  
+  /**
+   * Calculate new width and height of image.
+   */
+  protected function CalculateNewWidthAndHeight() {
+    // Only calculate new width and height if keeping aspect-ratio. 
+    if($this->keepRatio) {
+
+      // Both new width and height are set.
+      if(isset($this->newWidth) && isset($this->newHeight)) {
+
+        // Use newWidth and newHeigh as min width/height, image should fit the area.
+        if($this->crop) {
+          $ratioWidth = $this->width/$this->newWidth;
+          $ratioHeight = $this->height/$this->newHeight;
+          $ratio = ($ratioWidth < $ratioHeight) ? $ratioWidth : $ratioHeight;
+          $this->cropWidth = $this->width / $ratio;
+          $this->cropHeight = $this->height / $ratio;
+        }      
+      
+        // Use newWidth and newHeigh as max width/height, image should not be larger.
+        else {
+         if($this->width > $this->height) {
+            $factor = (float)$this->newWidth / (float)$this->width;
+            $this->newHeight = $factor * $this->height;
+          } else {
+            $factor = (float)$this->newHeight / (float)$this->height;
+            $this->newWidth = $factor * $this->width;
+          }
+        }
+      } 
+     
+      // Use new width as max-width
+      elseif(isset($this->newWidth)) {
+        $factor = (float)$this->newWidth / (float)$this->width;
+        $this->newHeight = $factor * $this->height;
+      } 
+    
+      // Use new height as max-hight
+      elseif(isset($this->newHeight)) {
+        $factor = (float)$this->newHeight / (float)$this->height;
+        $this->newWidth = $factor * $this->width;
+      } 
+    }
+    
+    // Do not keep aspect ratio, but both newWidth and newHeight must be set
+    else {
+      $this->newWidth = isset($this->newWidth) ? $this->newWidth : $this->width;
+      $this->newHeight = isset($this->newHeight) ? $this->newHeight : $this->height;    
+    }    
+    return $this;
+  }
+  
+  
+  /**
+   * Resize the image and optionally store/cache the new imagefile. Output the image.
+   */
+  public function ResizeAndOutput() {
+    $this->Init()->CalculateNewWidthAndHeight();
+
+    // Use original image?
+    if(is_null($this->newWidth) && is_null($this->newHeight)) {
+      $this->Output($this->pathToImage);
+    }
+    
+    // Check cache before resizing.
+    $this->newFileName = $this->CreateFilename();
+    if(is_readable($this->newFileName)) {
+      $fileTime = filemtime($this->pathToImage);
+      $cacheTime = filemtime($this->newFileName);    
+      if($fileTime <= $cacheTime) {
+        $this->Output($this->newFileName);
+      }
+    }
+    
+    // Resize and output    
+    $this->Open()->ResizeAndSave();
+  }
+  
+
+  /**
+   * Resize, crop and output the image.
+   *
+   * @param $imageQuality number the quality to use when saving the file, default is full quality.
+   */
+  public function ResizeAndSave($imageQuality="100") {
+
+    //echo "{$this->width}:{$this->height}:{$this->mime}</br>";
+    //echo "{$this->cropWidth}:{$this->cropHeight}</br>";    
+    //echo "{$this->newWidth}:{$this->newHeight}</br>";
+
+    if($this->crop) {
+      $cropX = ($this->cropWidth/2) - ($this->newWidth/2);  
+      $cropY = ($this->cropHeight/2) - ($this->newHeight/2);  
+      $imgPreCrop = imagecreatetruecolor($this->cropWidth, $this->cropHeight);
+      $imageResized = imagecreatetruecolor($this->newWidth, $this->newHeight);
+      imagecopyresampled($imgPreCrop, $this->image, 0, 0, 0, 0, $this->cropWidth, $this->cropHeight, $this->width, $this->height);
+      imagecopyresampled($imageResized, $imgPreCrop, 0, 0, $cropX, $cropY, $this->newWidth, $this->newHeight, $this->newWidth, $this->newHeight);
+    } else {
+      $imageResized = imagecreatetruecolor($this->newWidth, $this->newHeight);
+      imagecopyresampled($imageResized, $this->image, 0, 0, 0, 0, $this->newWidth, $this->newHeight, $this->width, $this->height);
+    }
+      
+    switch($this->fileExtension)  
+    {  
+      case 'jpg':  
+      case 'jpeg':  
+        if(imagetypes() & IMG_JPG) {
+          if($this->saveFolder) {
+            imagejpeg($imageResized, $this->newFileName, $imageQuality);
+          }
+          $imgFunction = 'imagejpeg';
+        }  
+      break;  
+  
+      case 'gif':  
+        if (imagetypes() & IMG_GIF) {  
+          if($this->saveFolder) {
+            imagegif($imageResized, $this->newFileName);  
+          }
+          $imgFunction = 'imagegif';
+        }  
+      break;  
+    
+      case 'png':  
+        // Scale quality from 0-100 to 0-9 and invert setting as 0 is best, not 9  
+        $quality = 9 - round(($imageQuality/100) * 9);  
+        if (imagetypes() & IMG_PNG) {  
+          if($this->saveFolder) {
+            imagepng($imageResized, $this->newFileName, $quality);  
+          }
+          $imgFunction = 'imagepng';
+        }  
+      break;  
+      default:
+        $this->RaiseError('No support for this file extension.');
+      break;
+    }  
+    header('Content-type: ' . $this->mime);
+    header('Last-Modified: ' . gmdate("D, d M Y H:i:s",time()) . " GMT");
+    $imgFunction($imageResized);
+    exit;
+  }
+  
+  
+}  

LICENSE.txt

@@ -0,0 +1,2 @@
+This is a software solution to a general known problem.
+Free software. Use at own risk.

README.md

@@ -0,0 +1,26 @@
+Image conversion on the fly using PHP
+=====================================
+
+The `CImage.php` contains a class that can resize and crop images and output them to
+a webpage. The class has cache of generated images.
+
+The file `img.php` uses `CImage.php` to resize images. It is a usecase on how to use
+the class.
+
+The file `test.php` has some testcases that show the results of `img.php` with different
+settings.
+
+Start by reviewing the `test.php`, then have a look at `img.php` and finally go through 
+`CImage.php`.
+
+Enjoy.
+
+Mikael Roos (mos@dbwebb.se)
+
+
+Revision history
+----------------
+
+v0.1 (2012-04-25) 
+
+* Initial release after rewriting some older code I had lying around.

img.php

@@ -0,0 +1,34 @@
+<?php
+/**
+ * Resize images on the fly using cache.
+ * 
+ */
+error_reporting(-1);
+set_time_limit(20);
+
+// Append ending slash
+$pathToImages = __DIR__.'/img/';
+$pathToCache = __DIR__.'/cache/';
+
+// Get input from querystring
+$srcImage = isset($_GET['src']) ? $pathToImages . basename($_GET['src']) : null;
+$newWidth = isset($_GET['width'])  ? $_GET['width']  : (isset($_GET['w'])  ? $_GET['w']  : null);
+$newHeight = isset($_GET['height']) ? $_GET['height'] : (isset($_GET['h']) ? $_GET['h'] : null);
+$keepRatio = isset($_GET['no-ratio']) ? false : true; // Keep Aspect Ratio?
+$crop = isset($_GET['crop']) ? true : false; // Crop image?
+
+// Do some sanity checks
+!preg_match('/^[\w-\.]+$/', $srcImage) or die('Filename contains invalid characters.');
+if(isset($newWidth)) {
+  $newWidth < 1000 or die('To large width.');
+  $newWidth > 10 or die('To small width.');
+}
+if(isset($newHeight)) {
+  $newHeight < 1000 or die('To large height.');
+  $newHeight > 10 or die('To small height.');
+}
+
+// Create the image object
+require(__DIR__.'/CImage.php');
+$img = new CImage($srcImage, $newWidth, $newHeight, $keepRatio, $crop, null/*$pathToCache*/);
+$img->ResizeAndOutput();

test.php

@@ -0,0 +1,39 @@
+<!doctype html>
+<head>
+  <meta charset='utf-8'/>
+  <title>Testing img resizing using CImage.php</title>
+</head>
+<body>
+<h1>Testing <code>CImage.php</code> through <code>img.php</code></h1>
+<p>You can test any variation of resizing the images through <a href='img.php?src=wider.jpg&amp;w=200&amp;h=200'>img.php?src=wider.jpg&amp;w=200&amp;h=200</a> or <a href='img.php?src=higher.jpg&amp;w=200&amp;h=200'>img.php?src=higher.jpg&amp;w=200&amp;h=200</a></p>
+<p>Supported arguments throught the querystring are:</p>
+<ul>
+<li>h, height: h=200 sets the height to 200px.
+<li>w, width: w=200 sets the width to 200px.
+<li>crop: together with both h & w makes the image fit in the box.
+<li>no-ratio: do not keep aspect ratio.
+</ul>
+
+<table>
+<caption>Test cases</caption>
+<thead><tr><th>Testcase:</th><th>Result:</th></tr></thead>
+<tbody>
+  <tr><td>Original image of wider.jpg.</td><td><img src='img.php?src=wider.jpg' /></td></tr>
+  <tr><td>wider.jpg max width 200.</td><td><img src='img.php?src=wider.jpg&amp;w=200' /></td></tr>
+  <tr><td>wider.jpg max height 200.</td><td><img src='img.php?src=wider.jpg&amp;h=200' /></td></tr>
+  <tr><td>wider.jpg max width 200 and max height 200.</td><td><img src='img.php?src=wider.jpg&amp;w=200&amp;h=200' /></td></tr>
+  <tr><td>wider.jpg max width 200 and max height 200 and no-ratio.</td><td><img src='img.php?src=wider.jpg&amp;w=200&amp;h=200&amp;no-ratio' /></td></tr>
+  <tr><td>wider.jpg max width 200 and max height 200 and cropped.</td><td><img src='img.php?src=wider.jpg&amp;w=200&amp;h=200&amp;crop' /></td></tr>
+  <tr><td>wider.jpg max width 200 and max height 100 and cropped.</td><td><img src='img.php?src=wider.jpg&amp;w=200&amp;h=100&amp;crop' /></td></tr>
+  <tr><td>Original image of higher.jpg.</td><td><img src='img.php?src=higher.jpg' /></td></tr>
+  <tr><td>higher.jpg max width 200.</td><td><img src='img.php?src=higher.jpg&amp;w=200' /></td></tr>
+  <tr><td>higher.jpg max height 200.</td><td><img src='img.php?src=higher.jpg&amp;h=200' /></td></tr>
+  <tr><td>higher.jpg max width 200 and max height 200.</td><td><img src='img.php?src=higher.jpg&amp;w=200&amp;h=200' /></td></tr>
+  <tr><td>higher.jpg max width 200 and max height 200 and no-ratio.</td><td><img src='img.php?src=higher.jpg&amp;w=200&amp;h=200&amp;no-ratio' /></td></tr>
+  <tr><td>higher.jpg max width 200 and max height 200 and cropped.</td><td><img src='img.php?src=higher.jpg&amp;w=200&amp;h=200&amp;crop' /></td></tr>
+  <tr><td>higher.jpg max width 200 and max height 100 and cropped.</td><td><img src='img.php?src=higher.jpg&amp;w=200&amp;h=100&amp;crop' /></td></tr>
+</tbody>
+</table>
+
+</body>
+</html>