Image Resizer / Crop
This article is also available in the following languages:
A handy-dandy resize, crop component to be used in controllers rather than view.
First off, put the component in the appropriate folder: /controllers/components/p_image.php
Include the component in your controller:
The default image resolution is 75. It is also resampled rather than resized for better results when you have large images.
An example of resizing an image to be a maximum of 480 height (put this in your controller, not your view):
To create a square image of 100 x 100:
To crop the image from the center (in this case, a square):
Hope y'all find this useful.
<?php
class PImageComponent extends Object
{
/*
* PImageComponent: component to resize or crop images
* @author: Wendy Perkins aka The Perkster
* @website: http://www.perksterdesigns.com/ - Probably still not up to par
* @license: MIT
* @version: 0.8.3.1
*/
/*
* @param $cType - the conversion type: resize (default), resizeCrop (square), crop (from center)
* @param $id - image filename
* @param $imgFolder - the folder where the image is
* @param $newName - include extension (if desired)
* @param $newWidth - the max width or crop width
* @param $newHeight - the max height or crop height
* @param $quality - the quality of the image
* @param $bgcolor - this was from a previous option that was removed, but required for backward compatibility
*/
function resizeImage($cType = 'resize', $id, $imgFolder, $newName = false, $newWidth=false, $newHeight=false, $quality = 75, $bgcolor = false)
{
$img = $imgFolder . $id;
list($oldWidth, $oldHeight, $type) = getimagesize($img);
$ext = $this->image_type_to_extension($type);
//check to make sure that the file is writeable, if so, create destination image (temp image)
if (is_writeable($imgFolder))
{
if($newName){
$dest = $imgFolder . $newName;
} else {
$dest = $imgFolder . 'tmp_'.$id;
}
}
else
{
//if not let developer know
$imgFolder = substr($imgFolder, 0, strlen($imgFolder) -1);
$imgFolder = substr($imgFolder, strrpos($imgFolder, '\\') + 1, 20);
debug("You must allow proper permissions for image processing. And the folder has to be writable.");
debug("Run \"chmod 777 on '$imgFolder' folder\"");
exit();
}
//check to make sure that something is requested, otherwise there is nothing to resize.
//although, could create option for quality only
if ($newWidth OR $newHeight)
{
/*
* check to make sure temp file doesn't exist from a mistake or system hang up.
* If so delete.
*/
if(file_exists($dest))
{
unlink($dest);
}
else
{
switch ($cType){
default:
case 'resize':
# Maintains the aspect ration of the image and makes sure that it fits
# within the maxW(newWidth) and maxH(newHeight) (thus some side will be smaller)
$widthScale = 2;
$heightScale = 2;
if($newWidth) $widthScale = $newWidth / $oldWidth;
if($newHeight) $heightScale = $newHeight / $oldHeight;
//debug("W: $widthScale H: $heightScale<br>");
if($widthScale < $heightScale) {
$maxWidth = $newWidth;
$maxHeight = false;
} elseif ($widthScale > $heightScale ) {
$maxHeight = $newHeight;
$maxWidth = false;
} else {
$maxHeight = $newHeight;
$maxWidth = $newWidth;
}
if($maxWidth > $maxHeight){
$applyWidth = $maxWidth;
$applyHeight = ($oldHeight*$applyWidth)/$oldWidth;
} elseif ($maxHeight > $maxWidth) {
$applyHeight = $maxHeight;
$applyWidth = ($applyHeight*$oldWidth)/$oldHeight;
} else {
$applyWidth = $maxWidth;
$applyHeight = $maxHeight;
}
//debug("mW: $maxWidth mH: $maxHeight<br>");
//debug("aW: $applyWidth aH: $applyHeight<br>");
$startX = 0;
$startY = 0;
//exit();
break;
case 'resizeCrop':
// -- resize to max, then crop to center
$ratioX = $newWidth / $oldWidth;
$ratioY = $newHeight / $oldHeight;
if ($ratioX < $ratioY) {
$startX = round(($oldWidth - ($newWidth / $ratioY))/2);
$startY = 0;
$oldWidth = round($newWidth / $ratioY);
$oldHeight = $oldHeight;
} else {
$startX = 0;
$startY = round(($oldHeight - ($newHeight / $ratioX))/2);
$oldWidth = $oldWidth;
$oldHeight = round($newHeight / $ratioX);
}
$applyWidth = $newWidth;
$applyHeight = $newHeight;
break;
case 'crop':
// -- a straight centered crop
$startY = ($oldHeight - $newHeight)/2;
$startX = ($oldWidth - $newWidth)/2;
$oldHeight = $newHeight;
$applyHeight = $newHeight;
$oldWidth = $newWidth;
$applyWidth = $newWidth;
break;
}
switch($ext)
{
case 'gif' :
$oldImage = imagecreatefromgif($img);
break;
case 'png' :
$oldImage = imagecreatefrompng($img);
break;
case 'jpg' :
case 'jpeg' :
$oldImage = imagecreatefromjpeg($img);
break;
default :
//image type is not a possible option
return false;
break;
}
//create new image
$newImage = imagecreatetruecolor($applyWidth, $applyHeight);
if($bgcolor):
//set up background color for new image
sscanf($bgcolor, "%2x%2x%2x", $red, $green, $blue);
$newColor = ImageColorAllocate($newImage, $red, $green, $blue);
imagefill($newImage,0,0,$newColor);
endif;
//put old image on top of new image
imagecopyresampled($newImage, $oldImage, 0,0 , $startX, $startY, $applyWidth, $applyHeight, $oldWidth, $oldHeight);
switch($ext)
{
case 'gif' :
imagegif($newImage, $dest, $quality);
break;
case 'png' :
imagepng($newImage, $dest, $quality);
break;
case 'jpg' :
case 'jpeg' :
imagejpeg($newImage, $dest, $quality);
break;
default :
return false;
break;
}
imagedestroy($newImage);
imagedestroy($oldImage);
if(!$newName){
unlink($img);
rename($dest, $img);
}
return true;
}
} else {
return false;
}
}
function image_type_to_extension($imagetype)
{
if(empty($imagetype)) return false;
switch($imagetype)
{
case IMAGETYPE_GIF : return 'gif';
case IMAGETYPE_JPEG : return 'jpg';
case IMAGETYPE_PNG : return 'png';
case IMAGETYPE_SWF : return 'swf';
case IMAGETYPE_PSD : return 'psd';
case IMAGETYPE_BMP : return 'bmp';
case IMAGETYPE_TIFF_II : return 'tiff';
case IMAGETYPE_TIFF_MM : return 'tiff';
case IMAGETYPE_JPC : return 'jpc';
case IMAGETYPE_JP2 : return 'jp2';
case IMAGETYPE_JPX : return 'jpf';
case IMAGETYPE_JB2 : return 'jb2';
case IMAGETYPE_SWC : return 'swc';
case IMAGETYPE_IFF : return 'aiff';
case IMAGETYPE_WBMP : return 'wbmp';
case IMAGETYPE_XBM : return 'xbm';
default : return false;
}
}
}
?>
Include the component in your controller:
var $components = array('PImage', ...);
The default image resolution is 75. It is also resampled rather than resized for better results when you have large images.
An example of resizing an image to be a maximum of 480 height (put this in your controller, not your view):
if($this->PImage->resizeImage('resize', 'myimage.jpg', WWW_ROOT . 'img' . DS, false, false, 480))
{
e('Image resized!);
}
To create a square image of 100 x 100:
if($this->PImage->resizeImage('resizeCrop', 'myimage.jpg', WWW_ROOT . 'img' . DS, 'mysquare_image.jpg', 100, 100, 60))
{
e('Image resized!);
}
To crop the image from the center (in this case, a square):
if($this->PImage->resizeImage('crop', 'myimage.jpg', WWW_ROOT . 'img' . DS, 'mycropped_image.jpg', 250, 250))
{
e('Image resized!);
}
Hope y'all find this useful.
Here is a nice fix, thanks to Phally (Change is at around line 167):
Controller Class:
<?php case 'png' :imagepng($newImage, $dest, $quality);?>
to
Controller Class:
<?php case 'png' :imagepng($newImage, $dest, round(($quality / 10) - 1)); ?>
EDIT: I would also like to note that support for using the quality parameter with imagepng was added in PHP 5.1.2, if you're using anything below then replace with this instead:
Controller Class:
<?php case 'png' :imagepng($newImage, $dest); ?>
if($newWidth) {
if($newWidth > $oldWidth) $newWidth = $oldWidth; $widthScale = $newWidth / $oldWidth;
}
if($newHeight) { if($newHeight > $oldHeight) $newHeight = $oldHeight; $heightScale = $newHeight / $oldHeight;
}
in the 'resizeCrop' case:
if($newWidth > $oldWidth) $newWidth = $oldWidth; $ratioX = $newWidth / $oldWidth;
if($newHeight > $oldHeight) $newHeight = $oldHeight; $ratioY = $newHeight / $oldHeight;
Comments are closed for articles over a year old