Größe dynamisch große Bild, um die Miniaturansicht in PHP?

Können Sie einen Blick auf SimpleImage Klasse hier:

http://www.white-hat-web-design.co.uk/blog/resizing-images-with-php/

Ich benutze es und es ist ziemlich gut und einfach.
Im Grunde können Sie nur

include('SimpleImage.php');
$image = new SimpleImage();
$image->load('picture.jpg');
$image->resize(250,400);
$image->save('picture2.jpg');

Können Sie diese Vorverarbeitung einmal und zeigen neu erstellte Bild.

Meiner Meinung nach, der einfachste Weg wäre die Nutzung von imagemagick (http://phpsnips.com/snip-111#.UhT5XZJwok0):

<?php 
//Location to upload main image: 
$mainDir = $_SERVER['DOCUMENT_ROOT'].'/images/l/'; 
//Location to create the thumb image: 
$smalDir = $_SERVER['DOCUMENT_ROOT'].'/images/s/'; 
//Command to use: 
$command = '/usr/bin/convert'; 
//Thumbnail width: 
$size = 210; 
//Make sure we have an image: 
if(isset($_POST['submit'])){ 
    if(getimagesize($_FILES['photo']['tmp_name'])){ 
        $name = $_FILES['photo']['name']; 
        $uploadfile = $mainDir . $name; 
        move_uploaded_file($_FILES['photo']['tmp_name'], $uploadfile); 
        $lrgImg = $mainDir . $name; 
        $smlImg = $smalDir . $name; 
        $imageMagick = $command . " '". $lrgImg . "' -resize '$size' '" . $smlImg . "'";         
        shell_exec($imageMagick); 
    } 
    header("Location: /test.php"); 
    exit; 
}else{ 
?> 
    <form action=" <?php echo $_SERVER['PHP_SELF']; ?> " method="post" enctype="multipart/form-data">
        <p><input type="file" name="photo" /></p>
        <p><input type="submit" value="Upload!" name="submit" /></p>
    </form>
<?php 
    foreach(glob($smalDir.'*') as $img){ 
        echo ' <img src="'.str_replace($_SERVER['DOCUMENT_ROOT'], '',$img).'" /> '; 
    } 
} 
?>

Könnten Sie es auch tun, mit PHPGD (http://phpsnips.com/snip-5#.UhT5yJJwok0):

<?php 
function createThumbnail($imageDirectory, $imageName, $thumbDirectory, $thumbWidth, $quality){ 
    $details = getimagesize("$imageDirectory/$imageName") or die('Please only upload images.'); 
    $type = preg_replace('@^.+(?<=/)(.+)$@', '$1', $details['mime']); 
    eval('$srcImg = imagecreatefrom'.$type.'("$imageDirectory/$imageName");'); 
    $thumbHeight = $details[1] * ($thumbWidth / $details[0]); 
    $thumbImg = imagecreatetruecolor($thumbWidth, $thumbHeight); 
    imagecopyresampled($thumbImg, $srcImg, 0, 0, 0, 0, $thumbWidth, $thumbHeight,  
    $details[0], $details[1]); 
    eval('image'.$type.'($thumbImg, "$thumbDirectory/$imageName"'. 
    (($type=='jpeg')?', $quality':'').');'); 
    imagedestroy($srcImg); 
    imagedestroy($thumbImg); 
} 

foreach ($_FILES["pictures"]["error"] as $key => $error) { 
   if ($error == UPLOAD_ERR_OK) { 
       $tmp_name = $_FILES["pictures"]["tmp_name"][$key]; 
       $name = $_FILES["pictures"]["name"][$key]; 
       move_uploaded_file($tmp_name, "data/$name"); 
       createThumbnail("/location/of/main/image", $name, "/location/to/store/thumb", 120, 80); 
       //120 = thumb width  ::  80 = thumb quality (1-100) 
   } 
} 
?>

Aus Php.net:

2 main-Funktion, die Sie eventuell benötigen könnten:

1: imagecopyresampled

<?php
//The file
$filename = 'test.jpg';

//Set a maximum height and width
$width = 200;
$height = 200;

//Content type
header('Content-Type: image/jpeg');

//Get new dimensions
list($width_orig, $height_orig) = getimagesize($filename);

$ratio_orig = $width_orig/$height_orig;

if ($width/$height > $ratio_orig) {
   $width = $height*$ratio_orig;
} else {
   $height = $width/$ratio_orig;
}

//Resample
$image_p = imagecreatetruecolor($width, $height);
$image = imagecreatefromjpeg($filename);
imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig);

//Output
imagejpeg($image_p, null, 100);
?>

2: imagecopyresized

<?php
//File and new size
$filename = 'test.jpg';
$percent = 0.5;

//Content type
header('Content-Type: image/jpeg');

//Get new sizes
list($width, $height) = getimagesize($filename);
$newwidth = $width * $percent;
$newheight = $height * $percent;

//Load
$thumb = imagecreatetruecolor($newwidth, $newheight);
$source = imagecreatefromjpeg($filename);

//Resize
imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);

//Output
imagejpeg($thumb);
?>