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animgif_support.module in Animated gif support for image styles 7

Provides animated gif resizing support for the image styles.

Image crop will not work for animated GIFs. So se use image_resize for image_crop and image_scale instead of image_scale_and_crop if the processed image is GIF. Because of this effect replacement, the image dimensions sometimes generated wrong in HTML. This module's theme_image implementation solves this problem by leaving out width, height attributes for GIFs.

Developed by Dénes Szabó. denes.szabo@internode.hu http://internode.hu

File

animgif_support.module
View source 
<?php

/**
 * @file
 * Provides animated gif resizing support for the image styles.
 *
 * Image crop will not work for animated GIFs. So se use image_resize for
 * image_crop and image_scale instead of image_scale_and_crop if the processed
 * image is GIF. Because of this effect replacement, the image dimensions
 * sometimes generated wrong in HTML. This module's theme_image implementation
 * solves this problem by leaving out width, height attributes for GIFs.
 *
 *  Developed by Dénes Szabó.
 *  denes.szabo@internode.hu
 *  http://internode.hu
 */

/**
 * Implements hook_menu().
 */
function animgif_support_menu() {
  $items = array();
  $items['admin/config/media/animgif_support'] = [
    'title' => 'Animated GIF support settings',
    'description' => 'Settings page for animateg GIF support',
    'page callback' => 'drupal_get_form',
    'page arguments' => [
      'animgif_support_settings_form',
    ],
    'access callback' => 'user_access',
    'access arguments' => [
      'administer site configuration',
    ],
    'weight' => 20,
    'file' => 'animgif_support.admin.inc',
  ];
  return $items;
}

/**
 * Implements hook_theme_registry_alter().
 *
 * If you have own theme for image, then set the animgif_support_use_image_theme
 * variable to false. But check our image theme for image dimensions handling of
 * GIF images.
 */
function animgif_support_theme_registry_alter(&$theme_registry) {
  if (!empty($theme_registry['image']['function']) && variable_get('animgif_support_use_image_theme', TRUE)) {
    $theme_registry['image']['function'] = 'animgif_support_image';
  }
}

/**
 * Returns HTML for an image.
 *
 * @group themeable
 */
function animgif_support_image($variables) {
  $attributes = $variables['attributes'];
  $attributes['src'] = file_create_url($variables['path']);
  $parts = explode('?', $variables['path']);
  $mime = file_get_mimetype($parts[0]);
  if ('image/gif' == $mime) {

    // Remove dimensions if the image is gif - the effect's dimensions callback
    // gives back false data for animated GIFs (GIFs either).
    unset($variables['width']);
    unset($variables['height']);
  }
  foreach (array(
    'width',
    'height',
    'alt',
    'title',
  ) as $key) {
    if (isset($variables[$key])) {
      $attributes[$key] = $variables[$key];
    }
  }
  return '<img' . drupal_attributes($attributes) . ' />';
}

/**
 * Provides original effect - replace effect array.
 */
function animgif_support_effect_replaces() {
  $replace = array(
    'image_crop' => 'image_resize',
    'image_resize' => 'image_resize',
    'image_scale' => 'image_scale',
    'image_scale_and_crop' => 'image_scale',
  );

  // Allow other modules to change the style associations.
  drupal_alter('animgif_support_effect_replaces', $replace);
  return $replace;
}

/**
 * Implements hook_image_effect_info_alter().
 */
function animgif_support_image_effect_info_alter(&$effects) {
  $replaces = animgif_support_effect_replaces();
  foreach ($effects as $key => $data) {
    if (!empty($replaces[$key])) {
      $effects[$key]['original effect callback'] = $effects[$key]['effect callback'];
      $effects[$key]['gif effect'] = $replaces[$key];
      $effects[$key]['effect callback'] = 'animgif_support_' . $key . '_effect';
    }
  }
  return TRUE;
}

/**
 * Effect callback common function for overridden effects.
 */
function animgif_support_do_effect(&$image, $data, $original_effect) {
  $definitions = image_effect_definitions();
  if (!empty($definitions[$original_effect]['original effect callback'])) {
    if (animgif_support_is_gif($image->info)) {

      // Run gif effect instead of the original.
      // todo: check if it is not an animgif. Dunno how...
      $gif_effect = $definitions[$original_effect]['gif effect'];
      $func = 'animgif_support_' . $gif_effect . '_func';
      $func($image, $data);
    }
    else {

      // Call the original effect callback.
      $func = $definitions[$original_effect]['original effect callback'];
      $func($image, $data);
    }
  }
}

/**
 * Provides image_crop effect callback for animated GIFs.
 */
function animgif_support_image_crop_effect(&$image, $data) {
  animgif_support_do_effect($image, $data, 'image_crop');
}

/**
 * Provides image_resize effect callback for animated GIFs.
 */
function animgif_support_image_resize_effect(&$image, $data) {
  animgif_support_do_effect($image, $data, 'image_resize');
}

/**
 * Provides image_scale effect callback for animated GIFs.
 */
function animgif_support_image_scale_effect(&$image, $data) {
  animgif_support_do_effect($image, $data, 'image_scale');
}

/**
 * Provides image_scale_and_crop effect callback for animated GIFs.
 */
function animgif_support_image_scale_and_crop_effect(&$image, $data) {
  animgif_support_do_effect($image, $data, 'image_scale_and_crop');
}

/**
 * Image re-sizer function for animated GIFs.
 */
function animgif_support_image_resize_func(&$image, $data) {
  if (!animgif_support_image_resizer($image, $data['width'], $data['height'])) {
    watchdog('image', 'Gif Image resize failed using the gifresizer lib on %path (%mimetype, %dimensions)', array(
      '%path' => $image->source,
      '%mimetype' => $image->info['mime_type'],
      '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
    ), WATCHDOG_ERROR);
    return FALSE;
  }
  return TRUE;
}

/**
 * Image size scale function for animated GIFs.
 */
function animgif_support_image_scale_func(&$image, $data) {

  // Set sane default values.
  $data += array(
    'width' => NULL,
    'height' => NULL,
    'upscale' => FALSE,
  );
  $dimensions = $image->info;

  // If both dimensions are null we set the original width.
  if (empty($data['width']) && empty($data['height'])) {
    $data['width'] = $dimensions['width'];
  }

  // Scale the dimensions - if they don't change then we use our re-sizer, we
  // want to GD do not touch this image.
  image_dimensions_scale($dimensions, $data['width'], $data['height'], $data['upscale']);
  if (!animgif_support_image_resizer($image, $dimensions['width'], $dimensions['height'])) {
    watchdog('image', 'Gif Image resize failed using the gifresizer lib on %path (%mimetype, %dimensions)', array(
      '%path' => $image->source,
      '%mimetype' => $image->info['mime_type'],
      '%dimensions' => $image->info['width'] . 'x' . $image->info['height'],
    ), WATCHDOG_ERROR);
    return FALSE;
  }
  return TRUE;
}

/**
 * Resize the GIF using available libraries.
 *
 * @param string $source
 *   Original GIF image path.
 * @param string $destination
 *   Resized GIF image path.
 * @param int $width
 *   Width dimension to resize to.
 * @param int $height
 *   Height dimension to resize to.
 *
 * @return bool
 *   The success flag.
 */
function _animgif_support_resize_image($source, $destination, $width, $height) {
  $ret = TRUE;
  $active = variable_get('animgif_support_gif_handler', 'gifresizer');

  // Use ImageMagick class, if available.
  if ('imagick' == $active && extension_loaded('imagick')) {
    $imagick = new Imagick($source);
    $image = $imagick
      ->coalesceImages();
    foreach ($image as $frame) {
      $frame
        ->scaleimage($width, $height);
    }
    $image = $image
      ->deconstructImages();
    $ret = $image
      ->writeImages($destination, TRUE);
  }
  elseif ('gifresizer' == $active && libraries_load('gifresizer')) {

    // Use GIFResizer class, if available.
    $gr = new gifresizer();

    // Used for extracting GIF Animation Frames.
    $gr->temp_dir = file_directory_temp();

    // Resizing the animation into a new file.
    $gr
      ->resize($source, $destination, $width, $height);
    $ret = TRUE;
  }
  return $ret;
}

/**
 * Provides re-sizer for animated GIFs.
 */
function animgif_support_image_resizer(stdClass $image, $width, $height) {
  $file_path = NULL;
  $is_remote = FALSE;
  $width = (int) round($width);
  $height = (int) round($height);
  $tmp = file_directory_temp();
  $img_name = 'resized--' . time() . '--' . rand() . '.gif';
  $resized_image = $tmp . '/' . $img_name;
  $scheme = file_uri_scheme($image->source);
  $local_stream_wrappers = file_get_stream_wrappers(STREAM_WRAPPERS_LOCAL);

  // If we can determine the uri scheme and it's not local.
  if (!empty($scheme) && !isset($local_stream_wrappers[$scheme])) {

    // Get an external URL for it.
    $file_path = file_create_url($image->source);
    $is_remote = TRUE;
  }

  // If the file is local or we couldn't generate an external URL,
  // (try to) get a local real path.
  if (empty($file_path)) {
    $file_path = drupal_realpath($image->source);
    if (empty($file_path)) {
      watchdog('Animated GIF support', 'Could not get local file path or external URL for file URI %uri.', array(
        '%uri' => $image->source,
      ), WATCHDOG_ERROR);
      return FALSE;
    }
    $is_remote = FALSE;
  }

  // If the file is remote and we're saving it locally and
  // using the contents of the file we've already downloaded.
  if ($is_remote) {
    $file_contents = file_get_contents($file_path);
    $local_path = drupal_tempnam('temporary://', 'animgif_support') . '.gif';
    if (($temp_file = file_save_data($file_contents, $local_path, FILE_EXISTS_REPLACE)) === FALSE) {
      watchdog('Animated GIF support', 'Could not write data for resource %uri to local temporary file %temp. Aborting indexing of resource.', array(
        '%uri' => $file_path,
        '%temp' => $local_path,
      ), WATCHDOG_WARNING);
      return FALSE;
    }

    // As file_save_data() is hardcoded to save with FILE_STATUS_PERMANENT,
    // we need to Re-save with temporary status so file is garbage collected.
    $temp_file->status = 0;
    file_save($temp_file);
    $file_path = drupal_realpath($local_path);
  }
  if (_animgif_support_resize_image($file_path, $resized_image, $width, $height)) {

    // Get new file as resource.
    $image->resource = imagecreatefromgif($resized_image);
    $image->info['width'] = $width;
    $image->info['height'] = $height;
    $image->info['resized_animgif_uri'] = 'temporary://' . $img_name;
    $image->info['resized_animgif'] = $tmp . '/' . $resized_image;

    // Hack into the save method - we need to use our method because GD ruins
    // the gif animation.
    $image->toolkit = 'animgif';
    return TRUE;
  }
  return FALSE;
}

/**
 * Helper to write an image resource to a destination file.
 *
 * Actually it just moves the generated animgif to the proper place, beacuse the
 * GD uses imagegd() which is not proper there, it losts the animation.
 */
function image_animgif_save(stdClass $image, $destination) {
  $scheme = file_uri_scheme($destination);
  $return = FALSE;

  // Work around lack of stream wrapper support in imagejpeg() and imagepng().
  $local_wrappers = file_get_stream_wrappers(STREAM_WRAPPERS_LOCAL);
  if ($scheme && file_stream_wrapper_valid_scheme($scheme)) {
    if (isset($local_wrappers[$scheme])) {

      // Convert stream wrapper URI to normal path.
      $destination = drupal_realpath($destination);
    }
  }
  if (!empty($image->info['resized_animgif_uri'])) {
    $image->uri = $image->info['resized_animgif_uri'];
    $return = file_unmanaged_move($image->info['resized_animgif_uri'], $destination, FILE_EXISTS_REPLACE);
  }
  return $return;
}

/**
 * Implements hook_libraries_info().
 */
function animgif_support_libraries_info() {

  // A very simple library. No changing APIs (hence, no versions), no variants.
  // Expected to be extracted into 'sites/all/libraries/simple'.
  $libraries['gifresizer'] = array(
    'name' => 'Gifresizer library',
    'vendor url' => 'http://www.phpclasses.org/package/7353-PHP-Resize-animations-in-files-of-the-GIF-format.html',
    'download url' => 'http://www.phpclasses.org/package/7353-PHP-Resize-animations-in-files-of-the-GIF-format.html#download',
    'version callback' => 'animgif_support_gifresizer_version_callback',
    'files' => array(
      'php' => array(
        'gifresizer.php',
      ),
    ),
  );
  return $libraries;
}

/**
 * Provides version callback for gifresizer lib.
 */
function animgif_support_gifresizer_version_callback() {
  return TRUE;
}

/**
 * Helper function to check the image type is gif or not.
 */
function animgif_support_is_gif($info) {
  if ($info['mime_type'] == 'image/gif') {
    return TRUE;
  }
  if ($info['extension'] == 'gif') {
    return TRUE;
  }
  return FALSE;
}

Functions

Namesort descending Description
animgif_support_do_effect Effect callback common function for overridden effects.
animgif_support_effect_replaces Provides original effect - replace effect array.
animgif_support_gifresizer_version_callback Provides version callback for gifresizer lib.
animgif_support_image Returns HTML for an image.
animgif_support_image_crop_effect Provides image_crop effect callback for animated GIFs.
animgif_support_image_effect_info_alter Implements hook_image_effect_info_alter().
animgif_support_image_resizer Provides re-sizer for animated GIFs.
animgif_support_image_resize_effect Provides image_resize effect callback for animated GIFs.
animgif_support_image_resize_func Image re-sizer function for animated GIFs.
animgif_support_image_scale_and_crop_effect Provides image_scale_and_crop effect callback for animated GIFs.
animgif_support_image_scale_effect Provides image_scale effect callback for animated GIFs.
animgif_support_image_scale_func Image size scale function for animated GIFs.
animgif_support_is_gif Helper function to check the image type is gif or not.
animgif_support_libraries_info Implements hook_libraries_info().
animgif_support_menu Implements hook_menu().
animgif_support_theme_registry_alter Implements hook_theme_registry_alter().
image_animgif_save Helper to write an image resource to a destination file.
_animgif_support_resize_image Resize the GIF using available libraries.