cms/drupal/modules/system/image.gd.inc
changeset 541 e756a8c72c3d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cms/drupal/modules/system/image.gd.inc	Fri Sep 08 12:04:06 2017 +0200
@@ -0,0 +1,417 @@
+<?php
+
+/**
+ * @file
+ * GD2 toolkit for image manipulation within Drupal.
+ */
+
+/**
+ * @addtogroup image
+ * @{
+ */
+
+/**
+ * Retrieve settings for the GD2 toolkit.
+ */
+function image_gd_settings() {
+  if (image_gd_check_settings()) {
+    $form['status'] = array(
+      '#markup' => t('The GD toolkit is installed and working properly.')
+    );
+
+    $form['image_jpeg_quality'] = array(
+      '#type' => 'textfield',
+      '#title' => t('JPEG quality'),
+      '#description' => t('Define the image quality for JPEG manipulations. Ranges from 0 to 100. Higher values mean better image quality but bigger files.'),
+      '#size' => 10,
+      '#maxlength' => 3,
+      '#default_value' => variable_get('image_jpeg_quality', 75),
+      '#field_suffix' => t('%'),
+    );
+    $form['#element_validate'] = array('image_gd_settings_validate');
+
+    return $form;
+  }
+  else {
+    form_set_error('image_toolkit', t('The GD image toolkit requires that the GD module for PHP be installed and configured properly. For more information see <a href="@url">PHP\'s image documentation</a>.', array('@url' => 'http://php.net/image')));
+    return FALSE;
+  }
+}
+
+/**
+ * Validate the submitted GD settings.
+ */
+function image_gd_settings_validate($form, &$form_state) {
+  // Validate image quality range.
+  $value = $form_state['values']['image_jpeg_quality'];
+  if (!is_numeric($value) || $value < 0 || $value > 100) {
+    form_set_error('image_jpeg_quality', t('JPEG quality must be a number between 0 and 100.'));
+  }
+}
+
+/**
+ * Verify GD2 settings (that the right version is actually installed).
+ *
+ * @return
+ *   A boolean indicating if the GD toolkit is available on this machine.
+ */
+function image_gd_check_settings() {
+  // GD2 support is available.
+  return function_exists('imagegd2');
+}
+
+/**
+ * Scale an image to the specified size using GD.
+ *
+ * @param $image
+ *   An image object. The $image->resource, $image->info['width'], and
+ *   $image->info['height'] values will be modified by this call.
+ * @param $width
+ *   The new width of the resized image, in pixels.
+ * @param $height
+ *   The new height of the resized image, in pixels.
+ * @return
+ *   TRUE or FALSE, based on success.
+ *
+ * @see image_resize()
+ */
+function image_gd_resize(stdClass $image, $width, $height) {
+  $res = image_gd_create_tmp($image, $width, $height);
+
+  if (!imagecopyresampled($res, $image->resource, 0, 0, 0, 0, $width, $height, $image->info['width'], $image->info['height'])) {
+    return FALSE;
+  }
+
+  imagedestroy($image->resource);
+  // Update image object.
+  $image->resource = $res;
+  $image->info['width'] = $width;
+  $image->info['height'] = $height;
+  return TRUE;
+}
+
+/**
+ * Rotate an image the given number of degrees.
+ *
+ * @param $image
+ *   An image object. The $image->resource, $image->info['width'], and
+ *   $image->info['height'] values will be modified by this call.
+ * @param $degrees
+ *   The number of (clockwise) degrees to rotate the image.
+ * @param $background
+ *   An hexadecimal integer specifying the background color to use for the
+ *   uncovered area of the image after the rotation. E.g. 0x000000 for black,
+ *   0xff00ff for magenta, and 0xffffff for white. For images that support
+ *   transparency, this will default to transparent. Otherwise it will
+ *   be white.
+ * @return
+ *   TRUE or FALSE, based on success.
+ *
+ * @see image_rotate()
+ */
+function image_gd_rotate(stdClass $image, $degrees, $background = NULL) {
+  // PHP installations using non-bundled GD do not have imagerotate.
+  if (!function_exists('imagerotate')) {
+    watchdog('image', 'The image %file could not be rotated because the imagerotate() function is not available in this PHP installation.', array('%file' => $image->source));
+    return FALSE;
+  }
+
+  // PHP 5.5 GD bug: https://bugs.php.net/bug.php?id=65148: To prevent buggy
+  // behavior on negative multiples of 90 degrees we convert any negative
+  // angle to a positive one between 0 and 360 degrees.
+  $degrees -= floor($degrees / 360) * 360;
+
+  // Convert the hexadecimal background value to a RGBA array.
+  if (isset($background)) {
+    $background = array(
+      'red' => $background >> 16 & 0xFF,
+      'green' => $background >> 8 & 0xFF,
+      'blue' => $background & 0xFF,
+      'alpha' => 0,
+    );
+  }
+  else {
+    // Background color is not specified: use transparent white as background.
+    $background = array(
+      'red' => 255,
+      'green' => 255,
+      'blue' => 255,
+      'alpha' => 127
+    );
+  }
+
+  // Store the color index for the background as that is what GD uses.
+  $background_idx = imagecolorallocatealpha($image->resource, $background['red'], $background['green'], $background['blue'], $background['alpha']);
+
+  // Images are assigned a new color palette when rotating, removing any
+  // transparency flags. For GIF images, keep a record of the transparent color.
+  if ($image->info['extension'] == 'gif') {
+    // GIF does not work with a transparency channel, but can define 1 color
+    // in its palette to act as transparent.
+
+    // Get the current transparent color, if any.
+    $gif_transparent_id = imagecolortransparent($image->resource);
+    if ($gif_transparent_id !== -1) {
+      // The gif already has a transparent color set: remember it to set it on
+      // the rotated image as well.
+      $transparent_gif_color = imagecolorsforindex($image->resource, $gif_transparent_id);
+
+      if ($background['alpha'] >= 127) {
+        // We want a transparent background: use the color already set to act
+        // as transparent, as background.
+        $background_idx = $gif_transparent_id;
+      }
+    }
+    else {
+      // The gif does not currently have a transparent color set.
+      if ($background['alpha'] >= 127) {
+        // But as the background is transparent, it should get one.
+        $transparent_gif_color = $background;
+      }
+    }
+  }
+
+  $image->resource = imagerotate($image->resource, 360 - $degrees, $background_idx);
+
+  // GIFs need to reassign the transparent color after performing the rotate.
+  if (isset($transparent_gif_color)) {
+    $background = imagecolorexactalpha($image->resource, $transparent_gif_color['red'], $transparent_gif_color['green'], $transparent_gif_color['blue'], $transparent_gif_color['alpha']);
+    imagecolortransparent($image->resource, $background);
+  }
+
+  $image->info['width'] = imagesx($image->resource);
+  $image->info['height'] = imagesy($image->resource);
+  return TRUE;
+}
+
+/**
+ * Crop an image using the GD toolkit.
+ *
+ * @param $image
+ *   An image object. The $image->resource, $image->info['width'], and
+ *   $image->info['height'] values will be modified by this call.
+ * @param $x
+ *   The starting x offset at which to start the crop, in pixels.
+ * @param $y
+ *   The starting y offset at which to start the crop, in pixels.
+ * @param $width
+ *   The width of the cropped area, in pixels.
+ * @param $height
+ *   The height of the cropped area, in pixels.
+ * @return
+ *   TRUE or FALSE, based on success.
+ *
+ * @see image_crop()
+ */
+function image_gd_crop(stdClass $image, $x, $y, $width, $height) {
+  $res = image_gd_create_tmp($image, $width, $height);
+
+  if (!imagecopyresampled($res, $image->resource, 0, 0, $x, $y, $width, $height, $width, $height)) {
+    return FALSE;
+  }
+
+  // Destroy the original image and return the modified image.
+  imagedestroy($image->resource);
+  $image->resource = $res;
+  $image->info['width'] = $width;
+  $image->info['height'] = $height;
+  return TRUE;
+}
+
+/**
+ * Convert an image resource to grayscale.
+ *
+ * Note that transparent GIFs loose transparency when desaturated.
+ *
+ * @param $image
+ *   An image object. The $image->resource value will be modified by this call.
+ * @return
+ *   TRUE or FALSE, based on success.
+ *
+ * @see image_desaturate()
+ */
+function image_gd_desaturate(stdClass $image) {
+  // PHP installations using non-bundled GD do not have imagefilter.
+  if (!function_exists('imagefilter')) {
+    watchdog('image', 'The image %file could not be desaturated because the imagefilter() function is not available in this PHP installation.', array('%file' => $image->source));
+    return FALSE;
+  }
+
+  return imagefilter($image->resource, IMG_FILTER_GRAYSCALE);
+}
+
+/**
+ * GD helper function to create an image resource from a file.
+ *
+ * @param $image
+ *   An image object. The $image->resource value will populated by this call.
+ * @return
+ *   TRUE or FALSE, based on success.
+ *
+ * @see image_load()
+ */
+function image_gd_load(stdClass $image) {
+  $extension = str_replace('jpg', 'jpeg', $image->info['extension']);
+  $function = 'imagecreatefrom' . $extension;
+  if (function_exists($function) && $image->resource = $function($image->source)) {
+    if (imageistruecolor($image->resource)) {
+      return TRUE;
+    }
+    else {
+      // Convert indexed images to truecolor, copying the image to a new
+      // truecolor resource, so that filters work correctly and don't result
+      // in unnecessary dither.
+      $resource = image_gd_create_tmp($image, $image->info['width'], $image->info['height']);
+      if ($resource) {
+        imagecopy($resource, $image->resource, 0, 0, 0, 0, imagesx($resource), imagesy($resource));
+        imagedestroy($image->resource);
+        $image->resource = $resource;
+      }
+    }
+    return (bool) $image->resource;
+  }
+  return FALSE;
+}
+
+/**
+ * GD helper to write an image resource to a destination file.
+ *
+ * @param $image
+ *   An image object.
+ * @param $destination
+ *   A string file URI or path where the image should be saved.
+ * @return
+ *   TRUE or FALSE, based on success.
+ *
+ * @see image_save()
+ */
+function image_gd_save(stdClass $image, $destination) {
+  $scheme = file_uri_scheme($destination);
+  // Work around lack of stream wrapper support in imagejpeg() and imagepng().
+  if ($scheme && file_stream_wrapper_valid_scheme($scheme)) {
+    // If destination is not local, save image to temporary local file.
+    $local_wrappers = file_get_stream_wrappers(STREAM_WRAPPERS_LOCAL);
+    if (!isset($local_wrappers[$scheme])) {
+      $permanent_destination = $destination;
+      $destination = drupal_tempnam('temporary://', 'gd_');
+    }
+    // Convert stream wrapper URI to normal path.
+    $destination = drupal_realpath($destination);
+  }
+
+  $extension = str_replace('jpg', 'jpeg', $image->info['extension']);
+  $function = 'image' . $extension;
+  if (!function_exists($function)) {
+    return FALSE;
+  }
+  if ($extension == 'jpeg') {
+    $success = $function($image->resource, $destination, variable_get('image_jpeg_quality', 75));
+  }
+  else {
+    // Always save PNG images with full transparency.
+    if ($extension == 'png') {
+      imagealphablending($image->resource, FALSE);
+      imagesavealpha($image->resource, TRUE);
+    }
+    $success = $function($image->resource, $destination);
+  }
+  // Move temporary local file to remote destination.
+  if (isset($permanent_destination) && $success) {
+    return (bool) file_unmanaged_move($destination, $permanent_destination, FILE_EXISTS_REPLACE);
+  }
+  return $success;
+}
+
+/**
+ * Create a truecolor image preserving transparency from a provided image.
+ *
+ * @param $image
+ *   An image object.
+ * @param $width
+ *   The new width of the new image, in pixels.
+ * @param $height
+ *   The new height of the new image, in pixels.
+ * @return
+ *   A GD image handle.
+ */
+function image_gd_create_tmp(stdClass $image, $width, $height) {
+  $res = imagecreatetruecolor($width, $height);
+
+  if ($image->info['extension'] == 'gif') {
+    // Find out if a transparent color is set, will return -1 if no
+    // transparent color has been defined in the image.
+    $transparent = imagecolortransparent($image->resource);
+
+    if ($transparent >= 0) {
+      // Find out the number of colors in the image palette. It will be 0 for
+      // truecolor images.
+      $palette_size = imagecolorstotal($image->resource);
+      if ($palette_size == 0 || $transparent < $palette_size) {
+        // Set the transparent color in the new resource, either if it is a
+        // truecolor image or if the transparent color is part of the palette.
+        // Since the index of the transparency color is a property of the
+        // image rather than of the palette, it is possible that an image
+        // could be created with this index set outside the palette size (see
+        // http://stackoverflow.com/a/3898007).
+        $transparent_color = imagecolorsforindex($image->resource, $transparent);
+        $transparent = imagecolorallocate($res, $transparent_color['red'], $transparent_color['green'], $transparent_color['blue']);
+
+        // Flood with our new transparent color.
+        imagefill($res, 0, 0, $transparent);
+        imagecolortransparent($res, $transparent);
+      }
+      else {
+        imagefill($res, 0, 0, imagecolorallocate($res, 255, 255, 255));
+      }
+    }
+  }
+  elseif ($image->info['extension'] == 'png') {
+    imagealphablending($res, FALSE);
+    $transparency = imagecolorallocatealpha($res, 0, 0, 0, 127);
+    imagefill($res, 0, 0, $transparency);
+    imagealphablending($res, TRUE);
+    imagesavealpha($res, TRUE);
+  }
+  else {
+    imagefill($res, 0, 0, imagecolorallocate($res, 255, 255, 255));
+  }
+
+  return $res;
+}
+
+/**
+ * Get details about an image.
+ *
+ * @param $image
+ *   An image object.
+ * @return
+ *   FALSE, if the file could not be found or is not an image. Otherwise, a
+ *   keyed array containing information about the image:
+ *   - "width": Width, in pixels.
+ *   - "height": Height, in pixels.
+ *   - "extension": Commonly used file extension for the image.
+ *   - "mime_type": MIME type ('image/jpeg', 'image/gif', 'image/png').
+ *
+ * @see image_get_info()
+ */
+function image_gd_get_info(stdClass $image) {
+  $details = FALSE;
+  $data = @getimagesize($image->source);
+
+  if (isset($data) && is_array($data)) {
+    $extensions = array('1' => 'gif', '2' => 'jpg', '3' => 'png');
+    $extension = isset($extensions[$data[2]]) ?  $extensions[$data[2]] : '';
+    $details = array(
+      'width'     => $data[0],
+      'height'    => $data[1],
+      'extension' => $extension,
+      'mime_type' => $data['mime'],
+    );
+  }
+
+  return $details;
+}
+
+/**
+ * @} End of "addtogroup image".
+ */