webmaster@1: <?php
webmaster@1: // $Id: image.inc,v 1.24 2008/01/28 16:05:17 goba Exp $
webmaster@1: 
webmaster@1: /**
webmaster@1:  * @file
webmaster@1:  * API for manipulating images.
webmaster@1:  */
webmaster@1: 
webmaster@1: /**
webmaster@1:  * @defgroup image Image toolkits
webmaster@1:  * @{
webmaster@1:  * Drupal's image toolkits provide an abstraction layer for common image file
webmaster@1:  * manipulations like scaling, cropping, and rotating. The abstraction frees
webmaster@1:  * module authors from the need to support multiple image libraries, and it
webmaster@1:  * allows site administrators to choose the library that's best for them.
webmaster@1:  *
webmaster@1:  * PHP includes the GD library by default so a GD toolkit is installed with
webmaster@1:  * Drupal. Other toolkits like ImageMagic are available from contrib modules.
webmaster@1:  * GD works well for small images, but using it with larger files may cause PHP
webmaster@1:  * to run out of memory. In contrast the ImageMagick library does not suffer
webmaster@1:  * from this problem, but it requires the ISP to have installed additional
webmaster@1:  * software.
webmaster@1:  *
webmaster@1:  * Image toolkits are installed by copying the image.ToolkitName.inc file into
webmaster@1:  * Drupal's includes directory. The toolkit must then be enabled using the
webmaster@1:  * admin/settings/image-toolkit form.
webmaster@1:  *
webmaster@1:  * Only one toolkit maybe selected at a time. If a module author wishes to call
webmaster@1:  * a specific toolkit they can check that it is installed by calling
webmaster@1:  * image_get_available_toolkits(), and then calling its functions directly.
webmaster@1:  */
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Return a list of available toolkits.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   An array of toolkit name => descriptive title.
webmaster@1:  */
webmaster@1: function image_get_available_toolkits() {
webmaster@1:   $toolkits = file_scan_directory('includes', 'image\..*\.inc$');
webmaster@1: 
webmaster@1:   $output = array();
webmaster@1:   foreach ($toolkits as $file => $toolkit) {
webmaster@1:     include_once "./$file";
webmaster@1:     $function = str_replace('.', '_', $toolkit->name) .'_info';
webmaster@1:     if (function_exists($function)) {
webmaster@1:       $info = $function();
webmaster@1:       $output[$info['name']] = $info['title'];
webmaster@1:     }
webmaster@1:   }
webmaster@1: 
webmaster@1:   return $output;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Retrieve the name of the currently used toolkit.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   String containing the name of the selected toolkit, or FALSE on error.
webmaster@1:  */
webmaster@1: function image_get_toolkit() {
webmaster@1:   static $toolkit;
webmaster@1: 
webmaster@1:   if (!$toolkit) {
webmaster@1:     $toolkit = variable_get('image_toolkit', 'gd');
webmaster@1:     $toolkit_file = './includes/image.'. $toolkit .'.inc';
webmaster@1:     if (isset($toolkit) && file_exists($toolkit_file)) {
webmaster@1:       include_once $toolkit_file;
webmaster@1:     }
webmaster@1:     elseif (!image_gd_check_settings()) {
webmaster@1:       $toolkit = FALSE;
webmaster@1:     }
webmaster@1:   }
webmaster@1: 
webmaster@1:   return $toolkit;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Invokes the given method using the currently selected toolkit.
webmaster@1:  *
webmaster@1:  * @param $method
webmaster@1:  *   A string containing the method to invoke.
webmaster@1:  * @param $params
webmaster@1:  *   An optional array of parameters to pass to the toolkit method.
webmaster@1:  * @return
webmaster@1:  *   Mixed values (typically Boolean indicating successful operation).
webmaster@1:  */
webmaster@1: function image_toolkit_invoke($method, $params = array()) {
webmaster@1:   if ($toolkit = image_get_toolkit()) {
webmaster@1:     $function = 'image_'. $toolkit .'_'. $method;
webmaster@1:     if (function_exists($function)) {
webmaster@1:       return call_user_func_array($function, $params);
webmaster@1:     }
webmaster@1:     else {
webmaster@1:       watchdog('php', 'The selected image handling toolkit %toolkit can not correctly process %function.', array('%toolkit' => $toolkit, '%function' => $function), WATCHDOG_ERROR);
webmaster@1:       return FALSE;
webmaster@1:     }
webmaster@1:   }
webmaster@1: }
webmaster@1: 
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Get details about an image.
webmaster@1:  *
webmaster@1:  * Drupal only supports GIF, JPG and PNG file formats.
webmaster@1:  *
webmaster@1:  * @return
webmaster@1:  *   FALSE, if the file could not be found or is not an image. Otherwise, a
webmaster@1:  *   keyed array containing information about the image:
webmaster@1:  *    'width'     - Width in pixels.
webmaster@1:  *    'height'    - Height in pixels.
webmaster@1:  *    'extension' - Commonly used file extension for the image.
webmaster@1:  *    'mime_type' - MIME type ('image/jpeg', 'image/gif', 'image/png').
webmaster@1:  *    'file_size' - File size in bytes.
webmaster@1:  */
webmaster@1: function image_get_info($file) {
webmaster@1:   if (!is_file($file)) {
webmaster@1:     return FALSE;
webmaster@1:   }
webmaster@1: 
webmaster@1:   $details = FALSE;
webmaster@1:   $data = @getimagesize($file);
webmaster@1:   $file_size = @filesize($file);
webmaster@1: 
webmaster@1:   if (isset($data) && is_array($data)) {
webmaster@1:     $extensions = array('1' => 'gif', '2' => 'jpg', '3' => 'png');
webmaster@1:     $extension = array_key_exists($data[2], $extensions) ?  $extensions[$data[2]] : '';
webmaster@1:     $details = array('width'     => $data[0],
webmaster@1:                      'height'    => $data[1],
webmaster@1:                      'extension' => $extension,
webmaster@1:                      'file_size' => $file_size,
webmaster@1:                      'mime_type' => $data['mime']);
webmaster@1:   }
webmaster@1: 
webmaster@1:   return $details;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Scales an image to the exact width and height given. Achieves the
webmaster@1:  * target aspect ratio by cropping the original image equally on both
webmaster@1:  * sides, or equally on the top and bottom.  This function is, for
webmaster@1:  * example, useful to create uniform sized avatars from larger images.
webmaster@1:  *
webmaster@1:  * The resulting image always has the exact target dimensions.
webmaster@1:  *
webmaster@1:  * @param $source
webmaster@1:  *   The file path of the source image.
webmaster@1:  * @param $destination
webmaster@1:  *   The file path of the destination image.
webmaster@1:  * @param $width
webmaster@1:  *   The target width, in pixels.
webmaster@1:  * @param $height
webmaster@1:  *   The target height, in pixels.
webmaster@1:  * @return
webmaster@1:  *   TRUE or FALSE, based on success.
webmaster@1:  */
webmaster@1: function image_scale_and_crop($source, $destination, $width, $height) {
webmaster@1:   $info = image_get_info($source);
webmaster@1: 
webmaster@1:   $scale = max($width / $info['width'], $height / $info['height']);
webmaster@1:   $x = round(($info['width'] * $scale - $width) / 2);
webmaster@1:   $y = round(($info['height'] * $scale - $height) / 2);
webmaster@1: 
webmaster@1:   if (image_toolkit_invoke('resize', array($source, $destination, $info['width'] * $scale, $info['height'] * $scale))) {
webmaster@1:     return image_toolkit_invoke('crop', array($destination, $destination, $x, $y, $width, $height));
webmaster@1:   }
webmaster@1:   return FALSE;
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Scales an image to the given width and height while maintaining aspect
webmaster@1:  * ratio.
webmaster@1:  *
webmaster@1:  * The resulting image can be smaller for one or both target dimensions.
webmaster@1:  *
webmaster@1:  * @param $source
webmaster@1:  *   The file path of the source image.
webmaster@1:  * @param $destination
webmaster@1:  *   The file path of the destination image.
webmaster@1:  * @param $width
webmaster@1:  *   The target width, in pixels.
webmaster@1:  * @param $height
webmaster@1:  *   The target height, in pixels.
webmaster@1:  * @return
webmaster@1:  *   TRUE or FALSE, based on success.
webmaster@1:  */
webmaster@1: function image_scale($source, $destination, $width, $height) {
webmaster@1:   $info = image_get_info($source);
webmaster@1: 
webmaster@1:   // Don't scale up.
webmaster@1:   if ($width >= $info['width'] && $height >= $info['height']) {
webmaster@1:     return FALSE;
webmaster@1:   }
webmaster@1: 
webmaster@1:   $aspect = $info['height'] / $info['width'];
webmaster@1:   if ($aspect < $height / $width) {
webmaster@1:     $width = (int)min($width, $info['width']);
webmaster@1:     $height = (int)round($width * $aspect);
webmaster@1:   }
webmaster@1:   else {
webmaster@1:     $height = (int)min($height, $info['height']);
webmaster@1:     $width = (int)round($height / $aspect);
webmaster@1:   }
webmaster@1: 
webmaster@1:   return image_toolkit_invoke('resize', array($source, $destination, $width, $height));
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Resize an image to the given dimensions (ignoring aspect ratio).
webmaster@1:  *
webmaster@1:  * @param $source
webmaster@1:  *   The file path of the source image.
webmaster@1:  * @param $destination
webmaster@1:  *   The file path of the destination image.
webmaster@1:  * @param $width
webmaster@1:  *   The target width, in pixels.
webmaster@1:  * @param $height
webmaster@1:  *   The target height, in pixels.
webmaster@1:   * @return
webmaster@1:  *   TRUE or FALSE, based on success.
webmaster@1:  */
webmaster@1: function image_resize($source, $destination, $width, $height) {
webmaster@1:   return image_toolkit_invoke('resize', array($source, $destination, $width, $height));
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Rotate an image by the given number of degrees.
webmaster@1:  *
webmaster@1:  * @param $source
webmaster@1:  *   The file path of the source image.
webmaster@1:  * @param $destination
webmaster@1:  *   The file path of the destination image.
webmaster@1:  * @param $degrees
webmaster@1:  *   The number of (clockwise) degrees to rotate the image.
webmaster@1:  * @param $background
webmaster@1:  *   An hexidecimal integer specifying the background color to use for the
webmaster@1:  *   uncovered area of the image after the rotation. E.g. 0x000000 for black,
webmaster@1:  *   0xff00ff for magenta, and 0xffffff for white.
webmaster@1:  * @return
webmaster@1:  *   TRUE or FALSE, based on success.
webmaster@1:  */
webmaster@1: function image_rotate($source, $destination, $degrees, $background = 0x000000) {
webmaster@1:   return image_toolkit_invoke('rotate', array($source, $destination, $degrees, $background));
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * Crop an image to the rectangle specified by the given rectangle.
webmaster@1:  *
webmaster@1:  * @param $source
webmaster@1:  *   The file path of the source image.
webmaster@1:  * @param $destination
webmaster@1:  *   The file path of the destination image.
webmaster@1:  * @param $x
webmaster@1:  *   The top left co-ordinate, in pixels, of the crop area (x axis value).
webmaster@1:  * @param $y
webmaster@1:  *   The top left co-ordinate, in pixels, of the crop area (y axis value).
webmaster@1:  * @param $width
webmaster@1:  *   The target width, in pixels.
webmaster@1:  * @param $height
webmaster@1:  *   The target height, in pixels.
webmaster@1:  * @return
webmaster@1:  *   TRUE or FALSE, based on success.
webmaster@1:  */
webmaster@1: function image_crop($source, $destination, $x, $y, $width, $height) {
webmaster@1:   return image_toolkit_invoke('crop', array($source, $destination, $x, $y, $width, $height));
webmaster@1: }
webmaster@1: 
webmaster@1: /**
webmaster@1:  * @} End of "defgroup image".
webmaster@1:  */