1 <?php

     2 // $Id: image.gd.inc,v 1.4 2008/01/15 10:17:42 goba Exp $

     3 

     4 /**

     5  * @file

     6  * GD2 toolkit for image manipulation within Drupal.

     7  */

     8 

     9 /**

    10  * @ingroup image

    11  * @{

    12  */

    13 

    14 /**

    15  * Retrieve information about the toolkit.

    16  */

    17 function image_gd_info() {

    18   return array('name' => 'gd', 'title' => t('GD2 image manipulation toolkit'));

    19 }

    20 

    21 /**

    22  * Retrieve settings for the GD2 toolkit.

    23  */

    24 function image_gd_settings() {

    25   if (image_gd_check_settings()) {

    26     $form = array();

    27     $form['status'] = array(

    28       '#value' => t('The GD toolkit is installed and working properly.')

    29     );

    30 

    31     $form['image_jpeg_quality'] = array(

    32       '#type' => 'textfield',

    33       '#title' => t('JPEG quality'),

    34       '#description' => t('Define the image quality for JPEG manipulations. Ranges from 0 to 100. Higher values mean better image quality but bigger files.'),

    35       '#size' => 10,

    36       '#maxlength' => 3,

    37       '#default_value' => variable_get('image_jpeg_quality', 75),

    38       '#field_suffix' => t('%'),

    39     );

    40     $form['#element_validate'] = array('image_gd_settings_validate');

    41     

    42     return $form;

    43   }

    44   else {

    45     form_set_error('image_toolkit', t('The 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')));

    46     return FALSE;

    47   }

    48 }

    49 

    50 /**

    51  * Validate the submitted GD settings.

    52  */

    53 function image_gd_settings_validate($form, &$form_state) {

    54   // Validate image quality range.

    55   $value = $form_state['values']['image_jpeg_quality'];

    56   if (!is_numeric($value) || $value < 0 || $value > 100) {

    57     form_set_error('image_jpeg_quality', t('JPEG quality must be a number between 0 and 100.'));

    58   }

    59 }

    60 

    61 /**

    62  * Verify GD2 settings (that the right version is actually installed).

    63  *

    64  * @return

    65  *   A boolean indicating if the GD toolkit is avaiable on this machine.

    66  */

    67 function image_gd_check_settings() {

    68   if ($check = get_extension_funcs('gd')) {

    69     if (in_array('imagegd2', $check)) {

    70       // GD2 support is available.

    71       return TRUE;

    72     }

    73   }

    74   return FALSE;

    75 }

    76 

    77 /**

    78  * Scale an image to the specified size using GD.

    79  */

    80 function image_gd_resize($source, $destination, $width, $height) {

    81   if (!file_exists($source)) {

    82     return FALSE;

    83   }

    84 

    85   $info = image_get_info($source);

    86   if (!$info) {

    87     return FALSE;

    88   }

    89 

    90   $im = image_gd_open($source, $info['extension']);

    91   if (!$im) {

    92     return FALSE;

    93   }

    94 

    95   $res = imagecreatetruecolor($width, $height);

    96   if ($info['extension'] == 'png') {

    97     $transparency = imagecolorallocatealpha($res, 0, 0, 0, 127);

    98     imagealphablending($res, FALSE);

    99     imagefilledrectangle($res, 0, 0, $width, $height, $transparency);

   100     imagealphablending($res, TRUE);

   101     imagesavealpha($res, TRUE);

   102   }

   103   elseif ($info['extension'] == 'gif') {

   104     // If we have a specific transparent color.

   105     $transparency_index = imagecolortransparent($im);

   106     if ($transparency_index >= 0) {

   107       // Get the original image's transparent color's RGB values.

   108       $transparent_color = imagecolorsforindex($im, $transparency_index);

   109       // Allocate the same color in the new image resource.

   110       $transparency_index = imagecolorallocate($res, $transparent_color['red'], $transparent_color['green'], $transparent_color['blue']);

   111       // Completely fill the background of the new image with allocated color.

   112       imagefill($res, 0, 0, $transparency_index);

   113       // Set the background color for new image to transparent.

   114       imagecolortransparent($res, $transparency_index);

   115       // Find number of colors in the images palette.

   116       $number_colors = imagecolorstotal($im);

   117       // Convert from true color to palette to fix transparency issues.

   118       imagetruecolortopalette($res, TRUE, $number_colors);

   119     }

   120   }

   121   imagecopyresampled($res, $im, 0, 0, 0, 0, $width, $height, $info['width'], $info['height']);

   122   $result = image_gd_close($res, $destination, $info['extension']);

   123 

   124   imagedestroy($res);

   125   imagedestroy($im);

   126 

   127   return $result;

   128 }

   129 

   130 /**

   131  * Rotate an image the given number of degrees.

   132  */

   133 function image_gd_rotate($source, $destination, $degrees, $background = 0x000000) {

   134   if (!function_exists('imageRotate')) {

   135     return FALSE;

   136   }

   137 

   138   $info = image_get_info($source);

   139   if (!$info) {

   140     return FALSE;

   141   }

   142 

   143   $im = image_gd_open($source, $info['extension']);

   144   if (!$im) {

   145     return FALSE;

   146   }

   147 

   148   $res = imageRotate($im, $degrees, $background);

   149   $result = image_gd_close($res, $destination, $info['extension']);

   150 

   151   return $result;

   152 }

   153 

   154 /**

   155  * Crop an image using the GD toolkit.

   156  */

   157 function image_gd_crop($source, $destination, $x, $y, $width, $height) {

   158   $info = image_get_info($source);

   159   if (!$info) {

   160     return FALSE;

   161   }

   162 

   163   $im = image_gd_open($source, $info['extension']);

   164   $res = imageCreateTrueColor($width, $height);

   165   imageCopy($res, $im, 0, 0, $x, $y, $width, $height);

   166   $result = image_gd_close($res, $destination, $info['extension']);

   167 

   168   imageDestroy($res);

   169   imageDestroy($im);

   170 

   171   return $result;

   172 }

   173 

   174 /**

   175  * GD helper function to create an image resource from a file.

   176  *

   177  * @param $file

   178  *   A string file path where the iamge should be saved.

   179  * @param $extension

   180  *   A string containing one of the following extensions: gif, jpg, jpeg, png.

   181  * @return

   182  *   An image resource, or FALSE on error.

   183  */

   184 function image_gd_open($file, $extension) {

   185   $extension = str_replace('jpg', 'jpeg', $extension);

   186   $open_func = 'imageCreateFrom'. $extension;

   187   if (!function_exists($open_func)) {

   188     return FALSE;

   189   }

   190   return $open_func($file);

   191 }

   192 

   193 /**

   194  * GD helper to write an image resource to a destination file.

   195  *

   196  * @param $res

   197  *   An image resource created with image_gd_open().

   198  * @param $destination

   199  *   A string file path where the iamge should be saved.

   200  * @param $extension

   201  *   A string containing one of the following extensions: gif, jpg, jpeg, png.

   202  * @return

   203  *   Boolean indicating success.

   204  */

   205 function image_gd_close($res, $destination, $extension) {

   206   $extension = str_replace('jpg', 'jpeg', $extension);

   207   $close_func = 'image'. $extension;

   208   if (!function_exists($close_func)) {

   209     return FALSE;

   210   }

   211   if ($extension == 'jpeg') {

   212     return $close_func($res, $destination, variable_get('image_jpeg_quality', 75));

   213   }

   214   else {

   215     return $close_func($res, $destination);

   216   }

   217 }

   218 

   219 /**

   220  * @} End of "ingroup image".

   221  */