diff --git a/SeedDMS_Preview/Preview/Previewer.php b/SeedDMS_Preview/Preview/Previewer.php
index 9f5aaf2f6..abe71d9c2 100644
--- a/SeedDMS_Preview/Preview/Previewer.php
+++ b/SeedDMS_Preview/Preview/Previewer.php
@@ -98,13 +98,22 @@ class SeedDMS_Preview_Previewer {
 				case "image/gif":
 				case "image/jpeg":
 				case "image/jpg":
+				case "image/svg+xml":
 					$cmd = 'convert -resize '.$width.'x'.$width.' '.$file.' '.$target;
 					break;
 				case "application/pdf":
+				case "application/postscript":
 					$cmd = 'convert -density 18 -resize '.$width.'x'.$width.' '.$file.'[0] '.$target;
+					break;
+				case "text/plain":
+					$cmd = 'convert -resize '.$width.'x'.$width.' '.$file.'[0] '.$target;
+					break;
+				case "application/x-compressed-tar":
+					$cmd = 'tar tzvf '.$file.' | convert -resize '.$width.'x'.$width.' text:-[0] '.$target;
+					break;
 			}
 			if($cmd) {
-				system( $cmd);
+				exec($cmd);
 			}
 			return true;
 		}