(PHP 4 >= 4.2.0, PHP 5)
exif_thumbnail — Retrieve the embedded thumbnail of a TIFF or JPEG image
$filename
   [, int &$width
   [, int &$height
   [, int &$imagetype
  ]]] )exif_thumbnail() reads the embedded thumbnail of a TIFF or JPEG image.
If you want to deliver thumbnails through this function, you should send the mimetype information using the header() function.
   It is possible that exif_thumbnail() cannot create an 
   image but can determine its size. In this case, the return value is 
   FALSE but width and height 
   are set.
  
filename
     The name of the image file being read. This image contains an embedded thumbnail.
width
     The return width of the returned thumbnail.
height
     The returned height of the returned thumbnail.
imagetype
     The returned image type of the returned thumbnail. This is either TIFF or JPEG.
   Returns the embedded thumbnail, or FALSE if the image contains no 
   thumbnail.
  
| Version | Description | 
|---|---|
| 4.3.0 | The optional parameters width,height, andimagetypeall became available. | 
| 4.3.0 | May return thumbnails in the TIFF format. | 
Example #1 exif_thumbnail() example
<?php
if (array_key_exists('file', $_REQUEST)) {
    $image = exif_thumbnail($_REQUEST['file'], $width, $height, $type);
} else {
    $image = false;
}
if ($image!==false) {
    header('Content-type: ' .image_type_to_mime_type($type));
    echo $image;
    exit;
} else {
    // no thumbnail available, handle the error here
    echo 'No thumbnail available';
}
?>