PHP Thumbnail Image script, quality looking funny on thumbnail.

Im having a problem with this script, the quality of the thumbnails looks very grainy.
I tried adding truecolour but it makes no difference.
Any help would be appreciated.
Regards Mike

      <?php
  error_reporting(0);

$val = $_GET['sid'];
	  mkdir("images/storyimg/$val/", 0777);
      $idir = "images/storyimg/$val";   // Path To Images Directory
      $tdir = "images/storyimg/$val/$val";   // Path To Thumbnails Directory
      $twidth = "180";   // Maximum Width For Thumbnail Images
      $theight = "180";   // Maximum Height For Thumbnail Images
      if (!isset($_GET['subpage'])) {   // Image Upload Form Below   ?>
        <form method="post" action="addphoto.php?subpage=upload" enctype="multipart/form-data">
         File:<br />
        <input type="file" name="imagefile" class="form">
        <br /><br />
        <input name="submit" type="submit" value="Sumbit" class="form">  <input type="reset" value="Clear" class="form">
        </form>
      <? } else  if (isset($_GET['subpage']) && $_GET['subpage'] == 'upload') {   // Uploading/Resizing Script
	  
        $url = $_FILES['imagefile']['name'];   // Set $url To Equal The Filename For Later Use
        if ($_FILES['imagefile']['type'] == "image/jpg" || $_FILES['imagefile']['type'] == "image/jpeg" || $_FILES['imagefile']['type'] == "image/pjpeg") {
          $file_ext = strrchr($_FILES['imagefile']['name'], '.'); 
	
		  // Get The File Extention In The Format Of , For Instance, .jpg, .gif or .php
          $copy = copy($_FILES['imagefile']['tmp_name'], "$idir" . $_FILES['imagefile']['name']);   // Move Image From Temporary Location To Permanent Location
          if ($copy) {   // If The Script Was Able To Copy The Image To It's Permanent Location
            print 'Image uploaded successfully.<br /><a href="javascript: history.go(-1)">Go Back</a>';   // Was Able To Successfully Upload Image
            $simg = imagecreatefromjpeg("$idir" . $url);   // Make A New Temporary Image To Create The Thumbanil From
            $currwidth = imagesx($simg);   // Current Image Width
            $currheight = imagesy($simg);   // Current Image Height
            if ($currheight > $currwidth) {   // If Height Is Greater Than Width
               $zoom = $twidth / $currheight;   // Length Ratio For Width
               $newheight = $theight;   // Height Is Equal To Max Height
               $newwidth = $currwidth * $zoom;   // Creates The New Width
            } else {    // Otherwise, Assume Width Is Greater Than Height (Will Produce Same Result If Width Is Equal To Height)
              $zoom = $twidth / $currwidth;   // Length Ratio For Height
              $newwidth = $twidth;   // Width Is Equal To Max Width
              $newheight = $currheight * $zoom;   // Creates The New Height
            }
            $dimg = imagecreate($newwidth, $newheight);   // Make New Image For Thumbnail
            imagetruecolortopalette($simg, true, 16777216);   // Create New Color Pallete
            $palsize = ImageColorsTotal($simg);
            for ($i = 0; $i < $palsize; $i++) {   // Counting Colors In The Image
             $colors = ImageColorsForIndex($simg, $i);   // Number Of Colors Used
             ImageColorAllocate($dimg, $colors['red'], $colors['green'], $colors['blue']);   // Tell The Server What Colors This Image Will Use
            }
            imagecopyresized($dimg, $simg, 0, 0, 0, 0, $newwidth, $newheight, $currwidth, $currheight);   // Copy Resized Image To The New Image (So We Can Save It)
            imagejpeg($dimg, "$tdir" . $url);   // Saving The Image
            imagedestroy($simg);   // Destroying The Temporary Image
            imagedestroy($dimg);   // Destroying The Other Temporary Image
            print 'Image thumbnail created successfully.';   // Resize successful
          } else {
            print '<font color="#FF0000">ERROR: Unable to upload image.</font>';   // Error Message If Upload Failed
          }
        } else {
          print '<font color="#FF0000">ERROR: Wrong filetype (has to be a .jpg or .jpeg. Yours is ';   // Error Message If Filetype Is Wrong
          print $file_ext;   // Show The Invalid File's Extention
          print '.</font>';
        }

      } ?>

PHP:

 

Hi Darksat,

why try to reinvent the wheel? You can achieve the same with much less code and PEAR, just to let you know.

HTTP_Upload

Image_Transform:

<?php
require_once 'Image/Transform.php';
$i =& Image_Transform::factory('');

$i->load('test.jpg');
$i->fit(100,100);
$i->save('resized.png', 'png');
?>

PHP:

Hope it helps.

 

I kind of need to get the existing code working if I can.

 

Bump.
Im sure its something fairly simple but the existing code works fine appart from the image pixelation.

 

I think what's happening is you're loading a JPEG and then converting it to a palette based image, then still outputting it as JPEG...

            $dimg = imagecreate($newwidth, $newheight);   // Make New Image For Thumbnail
            imagetruecolortopalette($simg, true, 16777216);   // Create New Color Pallete
            $palsize = ImageColorsTotal($simg);
            for ($i = 0; $i < $palsize; $i++) {   // Counting Colors In The Image
             $colors = ImageColorsForIndex($simg, $i);   // Number Of Colors Used
             ImageColorAllocate($dimg, $colors['red'], $colors['green'], $colors['blue']);   // Tell The Server What Colors This Image Will Use
            }

PHP:

to

            $dimg = imagecreatetruecolor($newwidth, $newheight);   // Make New Image For Thumbnail

PHP:

should fix it. Also try imagecopyresampled instead of imagecopyresized

 

should be

$zoom = $theight / $currheight; // Length Ratio For Width

otherwise your reduced pictures will be out of proportion