[Sommaire] [Imprimer]

   1  <?php
   2  // $Id: image.inc,v 1.17 2006/12/26 14:01:41 dries Exp $
   3  
   4  /**
   5   * Return a list of available toolkits.
   6   *
   7   * @return An array of toolkit name => descriptive title.
   8   */
   9  function image_get_available_toolkits() {
  10    $toolkits = file_scan_directory('includes', 'image\..*\.inc$');
  11  
  12    $output = array();
  13    foreach ($toolkits as $file => $toolkit) {
  14      include_once "./$file";
  15      $function = str_replace('.', '_', $toolkit->name) .'_info';
  16      if (function_exists($function)) {
  17        $info = $function();
  18        $output[$info['name']] = $info['title'];
  19      }
  20    }
  21    $output['gd'] = t('Built-in GD2 toolkit');
  22    return $output;
  23  }
  24  
  25  /**
  26   * Retrieve the name of the currently used toolkit.
  27   *
  28   * @return String containing the name of the toolkit.
  29   */
  30  function image_get_toolkit() {
  31    static $toolkit;
  32    if (!$toolkit) {
  33      $toolkit = variable_get('image_toolkit', 'gd');
  34     $toolkit_file = './includes/image.'.$toolkit.'.inc';
  35      if ($toolkit != 'gd' && file_exists($toolkit_file)) {
  36        include_once $toolkit_file;
  37      }
  38      elseif (!image_gd_check_settings()) {
  39        $toolkit = FALSE;
  40      }
  41    }
  42  
  43    return $toolkit;
  44  }
  45  
  46  /**
  47   * Invokes the given method using the currently selected toolkit.
  48   *
  49   * @param $method A string containing the method to invoke.
  50   * @param $params An optional array of parameters to pass to the toolkit method.
  51   *
  52   * @return Mixed values (typically Boolean for successful operation).
  53   */
  54  function image_toolkit_invoke($method, $params = array()) {
  55    if ($toolkit = image_get_toolkit()) {
  56      $function = 'image_'. $toolkit .'_'. $method;
  57      if (function_exists($function)) {
  58        return call_user_func_array($function, $params);
  59      }
  60      else {
  61        watchdog('php', t("The selected image handling toolkit %toolkit can not correctly process %function.", array('%toolkit' => $toolkit, '%function' => $function)), WATCHDOG_ERROR);
  62        return FALSE;
  63      }
  64    }
  65    else {
  66      if ($method == 'settings') {
  67        return image_gd_settings();
  68      }
  69    }
  70  }
  71  
  72  
  73  /**
  74   * Get details about an image.
  75   *
  76   * @return array containing information about the image
  77   *      'width': image's width in pixels
  78   *      'height': image's height in pixels
  79   *      'extension': commonly used extension for the image
  80   *      'mime_type': image's MIME type ('image/jpeg', 'image/gif', etc.)
  81   *      'file_size': image's physical size (in bytes)
  82   */
  83  function image_get_info($file) {
  84    if (!is_file($file)) {
  85      return FALSE;
  86    }
  87  
  88    $details = FALSE;
  89    $data = @getimagesize($file);
  90    $file_size = @filesize($file);
  91  
  92    if (isset($data) && is_array($data)) {
  93      $extensions = array('1' => 'gif', '2' => 'jpg', '3' => 'png');
  94      $extension = array_key_exists($data[2], $extensions) ?  $extensions[$data[2]] : '';
  95      $details = array('width'     => $data[0],
  96                       'height'    => $data[1],
  97                       'extension' => $extension,
  98                       'file_size' => $file_size,
  99                       'mime_type' => $data['mime']);
 100    }
 101  
 102    return $details;
 103  }
 104  
 105  /**
 106   * Scales an image to the given width and height while maintaining aspect
 107   * ratio.
 108   *
 109   * @param $source         The filepath of the source image
 110   * @param $destination    The file path of the destination image
 111   * @param $width          The target width
 112   * @param $height         The target height
 113   *
 114   * @return True or FALSE, based on success
 115   */
 116  function image_scale($source, $destination, $width, $height) {
 117    $info = image_get_info($source);
 118  
 119    // don't scale up
 120    if ($width >= $info['width'] && $height >= $info['height']) {
 121      return FALSE;
 122    }
 123  
 124    $aspect = $info['height'] / $info['width'];
 125    if ($aspect < $height / $width) {
 126      $width = (int)min($width, $info['width']);
 127      $height = (int)round($width * $aspect);
 128    }
 129    else {
 130      $height = (int)min($height, $info['height']);
 131      $width = (int)round($height / $aspect);
 132    }
 133  
 134    return image_toolkit_invoke('resize', array($source, $destination, $width, $height));
 135  }
 136  
 137  /**
 138   * Resize an image to the given dimensions (ignoring aspect ratio).
 139   *
 140   * @param $source        The filepath of the source image.
 141   * @param $destination   The file path of the destination image.
 142   * @param $width         The target width.
 143   * @param $height        The target height.
 144   */
 145  function image_resize($source, $destination, $width, $height) {
 146    return image_toolkit_invoke('resize', array($source, $destination, $width, $height));
 147  }
 148  
 149  /**
 150   * Rotate an image by the given number of degrees.
 151   *
 152   * @param $source  The filepath of the source image
 153   * @param $destination    The file path of the destination image
 154   * @param $degrees The number of (clockwise) degrees to rotate the image
 155   */
 156  function image_rotate($source, $destination, $degrees) {
 157    return image_toolkit_invoke('rotate', array($source, $destination, $degrees));
 158  }
 159  
 160  /**
 161   * Crop an image to the rectangle specified by the given rectangle.
 162   *
 163   * @param $source        The filepath of the source image
 164   * @param $destination   The file path of the destination image
 165   * @param $x             The top left co-ordinate of the crop area (x axis value)
 166   * @param $y             The top left co-ordinate of the crop area (y axis value)
 167   * @param $width         The target width
 168   * @param $height        The target height
 169   */
 170  function image_crop($source, $destination, $x, $y, $width, $height) {
 171    return image_toolkit_invoke('crop', array($source, $destination, $x, $y, $width, $height));
 172  }
 173  
 174  /**
 175   * GD2 toolkit functions
 176   * With the minimal requirements of PHP 4.3 for Drupal, we use the built-in version of GD.
 177   */
 178  
 179  /**
 180   * Retrieve settings for the GD2 toolkit.
 181   */
 182  function image_gd_settings() {
 183    if (image_gd_check_settings()) {
 184      $form = array();
 185      $form['status'] = array('#value' => t('The built-in GD2 toolkit is installed and working properly.'));
 186  
 187      $form['image_jpeg_quality'] = array(
 188        '#type' => 'textfield',
 189        '#title' => t('JPEG quality'),
 190        '#description' => t('Define the image quality for JPEG manipulations. Ranges from 0 to 100. Higher values mean better image quality but bigger files.'),
 191        '#size' => 10,
 192        '#maxlength' => 3,
 193        '#default_value' => variable_get('image_jpeg_quality', 75),
 194        '#field_suffix' => t('%'),
 195      );
 196  
 197      return $form;
 198    }
 199    else {
 200      form_set_error('image_toolkit', t('The built-in GD image toolkit requires that the GD module for PHP be installed and configured properly. For more information see <a href="@url">PHP\'s image documentation</a>.', array('@url' => 'http://php.net/image')));
 201      return FALSE;
 202    }
 203  }
 204  
 205  /**
 206   * Verify GD2 settings (that the right version is actually installed).
 207   *
 208   * @return boolean
 209   */
 210  function image_gd_check_settings() {
 211    if ($check = get_extension_funcs('gd')) {
 212      if (in_array('imagegd2', $check)) {
 213        // GD2 support is available.
 214        return TRUE;
 215      }
 216    }
 217    return FALSE;
 218  }
 219  
 220  /**
 221   * Scale an image to the specified size using GD.
 222   */
 223  function image_gd_resize($source, $destination, $width, $height) {
 224    if (!file_exists($source)) {
 225      return FALSE;
 226    }
 227  
 228    $info = image_get_info($source);
 229    if (!$info) {
 230      return FALSE;
 231    }
 232  
 233    $im = image_gd_open($source, $info['extension']);
 234    if (!$im) {
 235      return FALSE;
 236    }
 237  
 238    $res = imageCreateTrueColor($width, $height);
 239    if ($info['extension'] == 'png') {
 240      $transparency = imagecolorallocatealpha($res, 0, 0, 0, 127);
 241      imagealphablending($res, FALSE);
 242      imagefilledrectangle($res, 0, 0, $width, $height, $transparency);
 243      imagealphablending($res, TRUE);
 244      imagesavealpha($res, TRUE);
 245    }
 246    imageCopyResampled($res, $im, 0, 0, 0, 0, $width, $height, $info['width'], $info['height']);
 247    $result = image_gd_close($res, $destination, $info['extension']);
 248  
 249    imageDestroy($res);
 250    imageDestroy($im);
 251  
 252    return $result;
 253  }
 254  
 255  /**
 256   * Rotate an image the given number of degrees.
 257   */
 258  function image_gd_rotate($source, $destination, $degrees, $bg_color = 0) {
 259    if (!function_exists('imageRotate')) {
 260      return FALSE;
 261    }
 262  
 263    $info = image_get_info($source);
 264    if (!$info) {
 265      return FALSE;
 266    }
 267  
 268    $im = image_gd_open($source, $info['extension']);
 269    if (!$im) {
 270      return FALSE;
 271    }
 272  
 273    $res = imageRotate($im, $degrees, $bg_color);
 274    $result = image_gd_close($res, $destination, $info['extension']);
 275  
 276    return $result;
 277  }
 278  
 279  /**
 280   * Crop an image using the GD toolkit.
 281   */
 282  function image_gd_crop($source, $destination, $x, $y, $width, $height) {
 283    $info = image_get_info($source);
 284    if (!$info) {
 285      return FALSE;
 286    }
 287  
 288    $im = image_gd_open($source, $info['extension']);
 289    $res = imageCreateTrueColor($width, $height);
 290    imageCopy($res, $im, 0, 0, $x, $y, $width, $height);
 291    $result = image_gd_close($res, $destination, $info['extension']);
 292  
 293    imageDestroy($res);
 294    imageDestroy($im);
 295  
 296    return $result;
 297  }
 298  
 299  /**
 300   * GD helper function to create an image resource from a file.
 301   */
 302  function image_gd_open($file, $extension) {
 303    $extension = str_replace('jpg', 'jpeg', $extension);
 304    $open_func = 'imageCreateFrom'. $extension;
 305    if (!function_exists($open_func)) {
 306      return FALSE;
 307    }
 308    return $open_func($file);
 309  }
 310  
 311  /**
 312   * GD helper to write an image resource to a destination file.
 313   */
 314  function image_gd_close($res, $destination, $extension) {
 315    $extension = str_replace('jpg', 'jpeg', $extension);
 316    $close_func = 'image'. $extension;
 317    if (!function_exists($close_func)) {
 318      return FALSE;
 319    }
 320    if ($extension == 'jpeg') {
 321      return $close_func($res, $destination, variable_get('image_jpeg_quality', 75));
 322    }
 323    else {
 324      return $close_func($res, $destination);
 325    }
 326  }
 327  
 328