Here's my Image Resize Class. The Class can get the Result that you want (cropping/centered cropping/etc.)... and a lot more ;-)
I dont explain everything but if you got any questions just ask me.
<?php
final class Img {
/**
* Usage:
* Img::resizeImage( 'sample.png', null, array( 'x' => 150, 'y' => 150 ) )
* Outputs a Image
*
* Img::resizeImage( 'sample.png', 'crop.jpg', array( 'x' => 200, 'y' => 200 ) )
* Saves a Image
*
* @static
* @param string $source
* @param null|string $destination
* @param array $options
* @return void
* @throws Exception
*/
public static function resizeImage( $source, $destination = null, $options = array() ) {
if( !file_exists( $source ) || ( is_string( $destination ) && !is_writable( dirname( $destination ) ) ) ) {
throw new Exception( 'Quelldatei existiert nicht oder Zielverzeichnis ist nicht beschreibbar.' );
}
#@ini_set ('memory_limit', '64M' );
$defaultOptions = array(
'x' => 100,
'y' => 100,
'maxX' => 1000,
'maxY' => 1000,
'zoom_crop' => 1,
'quality' => 90,
'align' => 'c', // [c]enter, [b]ottom, [t]op, [l]eft, [r]ight
'filters' => '',
'sharpen' => 0,
'canvas' => 'ffffff',
);
$options = array_merge( $defaultOptions, $options );
$sData = getimagesize( $source );
$origType = $sData[2];
$mimeType = $sData['mime'];
if( !preg_match( '/^image\/(?:gif|jpg|jpeg|png)$/i', $mimeType ) ) {
throw new Exception( 'The image being resized is not a valid gif, jpg or png.' );
}
if( !function_exists( 'imagecreatetruecolor' ) ) {
throw new Exception( 'GD Library Error: imagecreatetruecolor does not exist' );
}
if( function_exists( 'imagefilter' ) && defined( 'IMG_FILTER_NEGATE' ) ) {
$imageFilters = array (
1 => array (IMG_FILTER_NEGATE, 0),
2 => array (IMG_FILTER_GRAYSCALE, 0),
3 => array (IMG_FILTER_BRIGHTNESS, 1),
4 => array (IMG_FILTER_CONTRAST, 1),
5 => array (IMG_FILTER_COLORIZE, 4),
6 => array (IMG_FILTER_EDGEDETECT, 0),
7 => array (IMG_FILTER_EMBOSS, 0),
8 => array (IMG_FILTER_GAUSSIAN_BLUR, 0),
9 => array (IMG_FILTER_SELECTIVE_BLUR, 0),
10 => array (IMG_FILTER_MEAN_REMOVAL, 0),
11 => array (IMG_FILTER_SMOOTH, 0),
);
}
$destX = min( $options['x'], $options['maxX'] );
$destY = min( $options['y'], $options['maxY'] );
switch( $mimeType ) {
case 'image/jpg':
case 'image/jpeg':
case 'image/pjgpg':
$image = imagecreatefromjpeg( $source );
break;
case 'image/png':
$image = imagecreatefrompng( $source );
break;
case 'image/gif':
$image = imagecreatefromgif( $source );
break;
}
if( !isset( $image ) ) {
throw new Exception( 'Could not open Image' );
}
$width = imagesx( $image );
$height = imagesy( $image );
$originX = $originY = 0;
if( $destX > 0 && $destY == 0 ) {
$destY = floor( $height * ( $destX / $width ) );
} else if( $destY > 0 && $destX == 0 ) {
$destX = floor( $width * ( $destY / $height ) );
}
// scale down and add borders
if( $options['zoom_crop'] == 3 ) {
$finalY = $height * ( $destX / $width );
if( $finalY > $destY ) {
$destX = $width * ( $destY / $height );
} else {
$destY = $finalY;
}
}
$canvas = imagecreatetruecolor( $destX, $destY );
imagealphablending( $canvas, false );
if( strlen( $options['canvas'] ) < 6 ) {
$options['canvas'] = 'ffffff';
}
$canvasColorR = hexdec( substr( $options['canvas'], 0, 2 ) );
$canvasColorG = hexdec( substr( $options['canvas'], 2, 2 ) );
$canvasColorB = hexdec( substr( $options['canvas'], 2, 2 ) );
// transparentes bild erstellen
$color = imagecolorallocatealpha( $canvas, $canvasColorR, $canvasColorG, $canvasColorB, 127 );
imagefill( $canvas, 0, 0, $color );
// scale down and add borders
if( $options['zoom_crop'] == 2 ) {
$finalY = $height * ( $destX / $width );
if( $finalY > $destY ) {
$originX = $destX / 2;
$destX = $width * ( $destY / $height );
$originX = round( $originX - ( $destX / 2 ) );
} else {
$originY = $destY / 2;
$destY = $finalY;
$originY = round( $originY - ( $destY / 2 ) );
}
}
// restore transparency blending
imagesavealpha( $canvas, true );
if( $options['zoom_crop'] > 0 ) {
$srcX = $srcY = 0;
$srcW = $width;
$srcH = $height;
$cmpX = $width / $destX;
$cmpY = $height / $destY;
// calculate x or y coordinate and width or height of source
if( $cmpX > $cmpY ) {
// breitformat
$srcW = round( $width / $cmpX * $cmpY );
$srcX = round( ( $width - ( $width / $cmpX * $cmpY ) ) / 2 );
} elseif( $cmpY > $cmpX ) {
$srcH = round( $height / $cmpY * $cmpX );
$srcY = round( ( $height - ( $height / $cmpY * $cmpX ) ) / 2 );
}
// pos cropping
if( strlen( $options['align'] ) ) {
if( strpos( $options['align'], 't') !== false) {
$srcY = 0;
}
if( strpos( $options['align'], 'b') !== false) {
$srcY = $height - $srcH;
}
if( strpos( $options['align'], 'l') !== false) {
$srcX = 0;
}
if( strpos( $options['align'], 'r') !== false) {
$srcX = $width - $srcW;
}
}
imagecopyresampled( $canvas, $image, $originX, $originY, $srcX, $srcY, $destX, $destY, $srcW, $srcH );
} else {
imagecopyresampled( $canvas, $image, 0, 0, 0, 0, $destX, $destY, $width, $height );
}
// @todo filtermöglichkeit über optionen ausbessern
if( strlen( $options['filters'] ) && function_exists( 'imagefilter' ) && defined( 'IMG_FILTER_NEGATE' ) ) {
// apply filters to image
$filterList = explode( '|', $options['filters'] );
foreach( $filterList as $fl ) {
$filterSettings = explode (',', $fl);
if (isset ($imageFilters[$filterSettings[0]])) {
for ($i = 0; $i < 4; $i ++) {
if (!isset ($filterSettings[$i])) {
$filterSettings[$i] = null;
} else {
$filterSettings[$i] = (int) $filterSettings[$i];
}
}
switch ($imageFilters[$filterSettings[0]][1]) {
case 1:
imagefilter ($canvas, $imageFilters[$filterSettings[0]][0], $filterSettings[1]);
break;
case 2:
imagefilter ($canvas, $imageFilters[$filterSettings[0]][0], $filterSettings[1], $filterSettings[2]);
break;
case 3:
imagefilter ($canvas, $imageFilters[$filterSettings[0]][0], $filterSettings[1], $filterSettings[2], $filterSettings[3]);
break;
case 4:
imagefilter ($canvas, $imageFilters[$filterSettings[0]][0], $filterSettings[1], $filterSettings[2], $filterSettings[3], $filterSettings[4]);
break;
default:
imagefilter ($canvas, $imageFilters[$filterSettings[0]][0]);
break;
}
}
}
}
if( $options['sharpen'] > 0 && function_exists( 'imageconvolution' ) ) {
$sharpenMatrix = array (
array (-1,-1,-1),
array (-1,16,-1),
array (-1,-1,-1),
);
$divisor = 8;
$offset = 0;
imageconvolution( $canvas, $sharpenMatrix, $divisor, $offset );
}
//Straight from Wordpress core code. Reduces filesize by up to 70% for PNG's
if( ( IMAGETYPE_PNG == $origType || IMAGETYPE_GIF == $origType ) &&
function_exists( 'imageistruecolor' ) && !imageistruecolor( $image ) &&
imagecolortransparent( $image ) > 0 ) {
imagetruecolortopalette( $canvas, false, imagecolorstotal( $image ) );
}
if( null === $destination ) {
header( "Cache-Control: no-store, no-cache, must-revalidate" );
header( "Cache-Control: post-check=0, pre-check=0", false);
header( "Pragma: no-cache" );
header( "Expires: Sat, 26 Jul 1997 05:00:00 GMT" );
header( "Last-Modified: " . date( "D, d M Y H:i:s" ) . " GMT" );
}
switch( $mimeType ) {
case 'image/jpg':
case 'image/jpeg':
case 'image/pjgpg':
if( null === $destination ) {
header("Content-type: image/jpeg");
}
@imagejpeg( $canvas, $destination, $options['quality'] );
break;
case 'image/png':
if( null === $destination ) {
header("Content-type: image/png");
}
@imagepng( $canvas, $destination, floor( $options['quality'] * 0.09 ) );
break;
case 'image/gif':
if( null === $destination ) {
header("Content-type: image/gif");
}
@imagegif( $canvas, $destination );
break;
default:
throw new Exception( 'Fehler beim schreiben' );
break;
}
imagedestroy( $canvas );
imagedestroy( $image );
}
}
