PHP test for corrupt (but apparently fine) images
//check if our image is OK
if ($image && $imageThumb)
{
    //check if image is a jpeg
    if (exif_imagetype($_FILES[$k]['tmp_name']) == IMAGETYPE_JPEG)
    {
        list($width, $height, $type, $attr) = getimagesize($_FILES[$k]['tmp_name']);
        //echo 1;
        $image = new SimpleImage();
        //echo 2;
        $image->load($_FILES[$k]['tmp_name']);
        //echo 3;
        $imageThumb = new SimpleImage();
        //echo 4;

        //this next line topples my script, but only for that one image - why?:
        $imageThumb->load($_FILES[$k]['tmp_name']);
        //echo '5<br/><br/>-------<br/>';
        //do stuff, save & update db, etc
    }
}