drupal/includes/image.inc

359 lines
10 KiB
PHP

<?php
// $Id$
/**
* Return a list of available toolkits.
*
* @return An array of toolkit name => descriptive title.
*/
function image_get_available_toolkits() {
$toolkits = file_scan_directory('includes', 'image\..*\.inc$');
$output = array();
foreach ($toolkits as $file => $toolkit) {
include_once "./$file";
$function = str_replace('.', '_', $toolkit->name) .'_info';
if (function_exists($function)) {
$info = $function();
$output[$info['name']] = $info['title'];
}
}
$output['gd'] = t('Built-in GD2 toolkit');
return $output;
}
/**
* Retrieve the name of the currently used toolkit.
*
* @return String containing the name of the toolkit.
*/
function image_get_toolkit() {
static $toolkit;
if (!$toolkit) {
$toolkit = variable_get('image_toolkit', 'gd');
$toolkit_file = './includes/image.'. $toolkit .'.inc';
if ($toolkit != 'gd' && file_exists($toolkit_file)) {
include_once $toolkit_file;
}
elseif (!image_gd_check_settings()) {
$toolkit = FALSE;
}
}
return $toolkit;
}
/**
* Invokes the given method using the currently selected toolkit.
*
* @param $method A string containing the method to invoke.
* @param $params An optional array of parameters to pass to the toolkit method.
*
* @return Mixed values (typically Boolean for successful operation).
*/
function image_toolkit_invoke($method, $params = array()) {
if ($toolkit = image_get_toolkit()) {
$function = 'image_'. $toolkit .'_'. $method;
if (function_exists($function)) {
return call_user_func_array($function, $params);
}
else {
watchdog('php', 'The selected image handling toolkit %toolkit can not correctly process %function.', array('%toolkit' => $toolkit, '%function' => $function), WATCHDOG_ERROR);
return FALSE;
}
}
else {
if ($method == 'settings') {
return image_gd_settings();
}
}
}
/**
* Get details about an image.
*
* @return array containing information about the image
* 'width': image's width in pixels
* 'height': image's height in pixels
* 'extension': commonly used extension for the image
* 'mime_type': image's MIME type ('image/jpeg', 'image/gif', etc.)
* 'file_size': image's physical size (in bytes)
*/
function image_get_info($file) {
if (!is_file($file)) {
return FALSE;
}
$details = FALSE;
$data = @getimagesize($file);
$file_size = @filesize($file);
if (isset($data) && is_array($data)) {
$extensions = array('1' => 'gif', '2' => 'jpg', '3' => 'png');
$extension = array_key_exists($data[2], $extensions) ? $extensions[$data[2]] : '';
$details = array('width' => $data[0],
'height' => $data[1],
'extension' => $extension,
'file_size' => $file_size,
'mime_type' => $data['mime']);
}
return $details;
}
/**
* Scales an image to the exact width and height given. Achieves the
* target aspect ratio by cropping the original image equally on both
* sides, or equally on the top and bottom. This function is, for
* example, useful to create uniform sized avatars from larger images.
*
* The resulting image always has the exact target dimensions.
*
* @param $source The file path of the source image
* @param $destination The file path of the destination image
* @param $width The target width
* @param $height The target height
*
* @return TRUE or FALSE, based on success
*/
function image_scale_and_crop($source, $destination, $width, $height) {
$info = image_get_info($source);
$scale = max($width / $info['width'], $height / $info['height']);
$x = round(($info['width'] * $scale - $width) / 2);
$y = round(($info['height'] * $scale - $height) / 2);
if (image_toolkit_invoke('resize', array($source, $destination, $info['width'] * $scale, $info['height'] * $scale))) {
return image_toolkit_invoke('crop', array($destination, $destination, $x, $y, $width, $height));
}
return FALSE;
}
/**
* Scales an image to the given width and height while maintaining aspect
* ratio.
*
* The resulting image can be smaller for one or both target dimensions.
*
* @param $source The file path of the source image
* @param $destination The file path of the destination image
* @param $width The target width
* @param $height The target height
*
* @return True or FALSE, based on success
*/
function image_scale($source, $destination, $width, $height) {
$info = image_get_info($source);
// Don't scale up.
if ($width >= $info['width'] && $height >= $info['height']) {
return FALSE;
}
$aspect = $info['height'] / $info['width'];
if ($aspect < $height / $width) {
$width = (int)min($width, $info['width']);
$height = (int)round($width * $aspect);
}
else {
$height = (int)min($height, $info['height']);
$width = (int)round($height / $aspect);
}
return image_toolkit_invoke('resize', array($source, $destination, $width, $height));
}
/**
* Resize an image to the given dimensions (ignoring aspect ratio).
*
* @param $source The filepath of the source image.
* @param $destination The file path of the destination image.
* @param $width The target width.
* @param $height The target height.
*/
function image_resize($source, $destination, $width, $height) {
return image_toolkit_invoke('resize', array($source, $destination, $width, $height));
}
/**
* Rotate an image by the given number of degrees.
*
* @param $source The filepath of the source image
* @param $destination The file path of the destination image
* @param $degrees The number of (clockwise) degrees to rotate the image
*/
function image_rotate($source, $destination, $degrees) {
return image_toolkit_invoke('rotate', array($source, $destination, $degrees));
}
/**
* Crop an image to the rectangle specified by the given rectangle.
*
* @param $source The filepath of the source image
* @param $destination The file path of the destination image
* @param $x The top left co-ordinate of the crop area (x axis value)
* @param $y The top left co-ordinate of the crop area (y axis value)
* @param $width The target width
* @param $height The target height
*/
function image_crop($source, $destination, $x, $y, $width, $height) {
return image_toolkit_invoke('crop', array($source, $destination, $x, $y, $width, $height));
}
/**
* GD2 toolkit functions
* With the minimal requirements of PHP 4.3 for Drupal, we use the built-in version of GD.
*/
/**
* Retrieve settings for the GD2 toolkit.
*/
function image_gd_settings() {
if (image_gd_check_settings()) {
$form = array();
$form['status'] = array('#value' => t('The built-in GD2 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('%'),
);
return $form;
}
else {
form_set_error('image_toolkit', t('The built-in GD image toolkit requires that the GD module for PHP be installed and configured properly. For more information see <a href="@url">PHP\'s image documentation</a>.', array('@url' => 'http://php.net/image')));
return FALSE;
}
}
/**
* Verify GD2 settings (that the right version is actually installed).
*
* @return boolean
*/
function image_gd_check_settings() {
if ($check = get_extension_funcs('gd')) {
if (in_array('imagegd2', $check)) {
// GD2 support is available.
return TRUE;
}
}
return FALSE;
}
/**
* Scale an image to the specified size using GD.
*/
function image_gd_resize($source, $destination, $width, $height) {
if (!file_exists($source)) {
return FALSE;
}
$info = image_get_info($source);
if (!$info) {
return FALSE;
}
$im = image_gd_open($source, $info['extension']);
if (!$im) {
return FALSE;
}
$res = imageCreateTrueColor($width, $height);
if ($info['extension'] == 'png') {
$transparency = imagecolorallocatealpha($res, 0, 0, 0, 127);
imagealphablending($res, FALSE);
imagefilledrectangle($res, 0, 0, $width, $height, $transparency);
imagealphablending($res, TRUE);
imagesavealpha($res, TRUE);
}
imageCopyResampled($res, $im, 0, 0, 0, 0, $width, $height, $info['width'], $info['height']);
$result = image_gd_close($res, $destination, $info['extension']);
imageDestroy($res);
imageDestroy($im);
return $result;
}
/**
* Rotate an image the given number of degrees.
*/
function image_gd_rotate($source, $destination, $degrees, $bg_color = 0) {
if (!function_exists('imageRotate')) {
return FALSE;
}
$info = image_get_info($source);
if (!$info) {
return FALSE;
}
$im = image_gd_open($source, $info['extension']);
if (!$im) {
return FALSE;
}
$res = imageRotate($im, $degrees, $bg_color);
$result = image_gd_close($res, $destination, $info['extension']);
return $result;
}
/**
* Crop an image using the GD toolkit.
*/
function image_gd_crop($source, $destination, $x, $y, $width, $height) {
$info = image_get_info($source);
if (!$info) {
return FALSE;
}
$im = image_gd_open($source, $info['extension']);
$res = imageCreateTrueColor($width, $height);
imageCopy($res, $im, 0, 0, $x, $y, $width, $height);
$result = image_gd_close($res, $destination, $info['extension']);
imageDestroy($res);
imageDestroy($im);
return $result;
}
/**
* GD helper function to create an image resource from a file.
*/
function image_gd_open($file, $extension) {
$extension = str_replace('jpg', 'jpeg', $extension);
$open_func = 'imageCreateFrom'. $extension;
if (!function_exists($open_func)) {
return FALSE;
}
return $open_func($file);
}
/**
* GD helper to write an image resource to a destination file.
*/
function image_gd_close($res, $destination, $extension) {
$extension = str_replace('jpg', 'jpeg', $extension);
$close_func = 'image'. $extension;
if (!function_exists($close_func)) {
return FALSE;
}
if ($extension == 'jpeg') {
return $close_func($res, $destination, variable_get('image_jpeg_quality', 75));
}
else {
return $close_func($res, $destination);
}
}