note 48912 deleted from function.imagecolortransparent by cmb

Note Submitter: webmaster at webnetwizard dotco dotuk ---- I'm feeling particularly altruistic today, so here is the code to accompany the text I submitted about a script that 'intelligently' detects if an uploaded GIF has transparency or not, and creates a thumbnail accordingly: if (move_uploaded_file($_FILES['userfile']['tmp_name'], $uploadfile)) { $note = "Image was successfully uploaded.\n"; // Now create thumbnail version of the uploaded image and save it to // folder "$fixPath/images/thumbs". First, we need to create a // resource "handle" for a copy of the uploaded image $img_error = false; list($width, $height, $type) = getimagesize($uploadfile); switch($type) // Allowed types: image/gif,image/jpeg,image/x-png { case 1: // GIF $src = @imagecreatefromgif($uploadfile); if (!$src) $img_error = true; break; case 2: // JPEG . . . case 3: // PNG . . . default: $img_error = true; } // resource handle for source image now in $src // Now calculate scaling factor and put in $sf if(!$img_error) { if($width >= $height && $width > 100) $sf = $width / 100; elseif($height > 100) $sf = $height / 100; else $sf = 1; $newwidth = intval($width / $sf); $newheight = intval($height / $sf); switch($type) // Allowed types: image/gif,image/jpeg,image/x-png { case 1: // GIF $tpcolor = imagecolorat($src, 0, 0); // in the real world, you'd better test all four corners, not just one! $dest = imagecreate($newwidth, $newheight); // $dest automatically has a black fill... imagepalettecopy($dest, $src); imagecopyresized($dest, $src, 0, 0, 0, 0, $newwidth, $newheight, $width, $height); $pixel_over_black = imagecolorat($dest, 0, 0); // ...but now make the fill white... $bg = imagecolorallocate($dest, 255, 255, 255); imagefilledrectangle($dest, 0, 0, $newwidth, $newheight, $bg); imagecopyresized($dest, $src, 0, 0, 0, 0, $newwidth, $newheight, $width, $height); $pixel_over_white = imagecolorat($dest, 0, 0); // ...to test if transparency causes the fill color to show through: if($pixel_over_black != $pixel_over_white) { // Background IS transparent imagefilledrectangle($dest, 0, 0, $newwidth, $newheight, $tpcolor); imagecopyresized($dest, $src, 0, 0, 0, 0, $newwidth, $newheight, $width, $height); imagecolortransparent($dest, $tpcolor); imagegif($dest, "$fixPath/images/thumbs/$userfile"); } else // Background (most probably) NOT transparent imagegif($dest, "$fixPath/images/thumbs/$userfile"); break; case 2: // JPEG . . . case 3: // PNG . . . break; } imagedestroy($src); imagedestroy($dest); } else $note = "Error: Uploaded image but could not create thumbnail"; header("location: $fixPath/index.php?next=$next&nb=$nb&userfile=$userfile"); } else $note = "Could not find anything to upload\n";