d7_to_d10_migration/drupal7/web/modules/system/image.gd.inc

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2024-07-23 03:38:34 +00:00
<?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) {
$width = (int) $width;
$height = (int) $height;
$res = image_gd_create_tmp($image, $width, $height);
if (!imagecopyresampled($res, $image->resource, 0, 0, (int) $x, (int) $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".
*/