<?php
/**
* Helper functions, many from Drupal
* http://drupal.org
*/
class ImageResize {
public function image_scale($source, $destination, $width, $height)
{
$info = ImageResize::image_get_info($source);
// don't scale up
if ($width > $info['width'] && $height > $info['height']) {
return false;
}
$aspect = $info['height'] / $info['width'];
if (!$height || ($width && $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 / $aspect);
}
return ImageResize::image_gd_resize($source, $destination, $width, $height);
}
public function image_scale_cropped($source, $destination, $width, $height)
{
$info = ImageResize::image_get_info($source);
// don't scale up
if ($width > $info['width'] && $height > $info['height']) {
return false;
}
/* If we are square. */
if (!$height || !$width || $height == $width) {
if ($info['width'] > $info['height']) {
$source_width = $source_height = $info['height'];
$source_y = 0;
$source_x = round(($info['width'] - $info['height']) / 2);
} else {
$source_width = $source_height = $info['width'];
$source_x = 0;
$source_y = round(($info['height'] - $info['width']) / 2);
}
if ($width) {
$height = $width;
} else {
$width = $height;
}
/* We are not square. */
} else {
$x_ratio = $width / $info['width'];
$y_ratio = $height / $info['height'];
if (($x_ratio * $info['width']) >= $width && ($x_ratio * $info['height']) >= $height) {
$aspect = $width / $height;
$x_ratio * $info['width'];
$source_width = $info['width'];
$source_height = round($source_width / $aspect);
$source_x = 0;
$source_y = round(($info['height'] - $source_height) / 2);
} else {
$aspect = $height / $width;
$source_height = $info['height'];
$source_width = round($source_height / $aspect);
$source_x = round(($info['width'] - $source_width) / 2);
$source_y = 0;
}
}
return ImageResize::image_gd_resize($source, $destination, $width, $height, $source_x, $source_y, $source_width, $source_height);
}
/**
* GD2 has to be available on the system
*
* @return boolean
*/
public function gd_available() {
if ($check = get_extension_funcs('gd')) {
if (in_array('imagegd2', $check)) {
// GD2 support is available.
return true;
}
}
return false;
}
/**
* Get details about an image.
*
* @return array containing information about the image
* 'width': image's width in pixels
* 'height': image's height in pixels
* 'extension': commonly used extension for the image
* 'mime_type': image's MIME type ('image/jpeg', 'image/gif', etc.)
*/
function image_get_info($file) {
if (!is_file($file)) {
return false;
}
$details = false;
$data = @getimagesize($file);
if (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,
'mime_type' => $data['mime']);
}
return $details;
}
/**
* Scale an image to the specified size using GD.
*/
function image_gd_resize($source, $destination, $width, $height, $source_x = 0, $source_y = 0, $source_width = null, $source_height = null) {
if (!file_exists($source)) {
return false;
}
$info = ImageResize::image_get_info($source);
if (!$info) {
return false;
}
$im = ImageResize::image_gd_open($source, $info['extension']);
if (!$im) {
return false;
}
/* Get source dimensions from GD info is not passed as parameters. */
$source_width = is_null($source_width) ? $info['width'] : $source_width;
$source_height = is_null($source_height) ? $info['height'] : $source_height;
$res = imageCreateTrueColor($width, $height);
imageCopyResampled($res, $im, 0, 0, $source_x, $source_y, $width, $height, $source_width, $source_height);
$result = ImageResize::image_gd_close($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;
}
return $close_func($res, $destination);
}
}
