diff --git a/filter/gstoraster.c b/filter/gstoraster.c
index 0c9f37d..820acc8 100644
--- a/filter/gstoraster.c
+++ b/filter/gstoraster.c
@@ -73,29 +73,23 @@ static GsDocType
 parse_doc_type(FILE *fp)
 {
   char buf[5];
-  GsDocType doc_type;
-  char *rc;
+  GsDocType type = GS_DOC_TYPE_UNKNOWN;
 
   /* get the first few bytes of the file */
-  doc_type = GS_DOC_TYPE_UNKNOWN;
   rewind(fp);
-  rc = fgets(buf,sizeof(buf),fp);
-  if (rc == NULL)
-    goto out;
-
-  /* is PDF */
-  if (strncmp(buf,"%PDF",4) == 0) {
-    doc_type = GS_DOC_TYPE_PDF;
-    goto out;
+/* skip until PDF/PS start header */
+ while (fgets(buf, sizeof(buf), fp) != 0) {
+   if (strncmp(buf, "%PDF", 4) == 0)
+     type = GS_DOC_TYPE_PDF;
+   if (strncmp(buf, "%!", 2) == 0)
+     type = GS_DOC_TYPE_PS;
+   if (type != GS_DOC_TYPE_UNKNOWN)
+     break;
   }
 
-  /* is PS */
-  if (strncmp(buf,"%!",2) == 0) {
-    doc_type = GS_DOC_TYPE_PS;
-    goto out;
-  }
-out:
-  return doc_type;
+  rewind(fp);
+
+  return (type);
 }
 
 static void