diff --git a/imageapi_imagemagick.module b/imageapi_imagemagick.module
index 3171d0b..fd74441 100644
--- a/imageapi_imagemagick.module
+++ b/imageapi_imagemagick.module
@@ -146,6 +146,18 @@ function imageapi_imagemagick_image_desaturate(&$image) {
  */
 function _imageapi_imagemagick_convert($source, $dest, $args) {
   $args['quality'] = '-quality '. escapeshellarg(variable_get('imageapi_imagemagick_quality', 75));
+
+  // If the file is missing an extension, or contains an invalid image
+  // extension; read the file and and set destination to new filename.
+  $pathinfo = pathinfo($source);
+  if (empty($pathinfo['extension']) || !ctype_alnum($pathinfo['extension']) || strlen($pathinfo['extension']) > 4) {
+    $extension = filefield_get_image_extension($source);
+    if (!empty($extension)) {
+      $old_dest = $dest;
+      $dest .= $extension;
+    }
+  }
+
   // To make use of ImageMagick 6's parenthetical command grouping we need to make
   // the $source image the first parameter and $dest the last.
   // See http://www.imagemagick.org/Usage/basics/#cmdline for more info.
@@ -154,6 +166,10 @@ function _imageapi_imagemagick_convert($source, $dest, $args) {
   if (0 != _imageapi_imagemagick_convert_exec($command, $output, $errors)) {
     return FALSE;
   }
+  // Copy the new file back to the orginal destination so orginal request works.
+  if (!empty($old_dest)) {
+    file_copy($dest, $old_dest);
+  }
   return file_exists($dest);
 }