diff --git a/src/file_emf.c b/src/file_emf.c
index 08760c6c..8b6dcf75 100644
--- a/src/file_emf.c
+++ b/src/file_emf.c
@@ -35,7 +35,7 @@
 #include "__fc_builtin.h"
 #endif
 
-/*@ requires \valid(file_stat); */
+/*@ requires valid_register_header_check(file_stat); */
 static void register_header_check_emf(file_stat_t *file_stat);
 
 const file_hint_t file_hint_emf= {
@@ -205,13 +205,10 @@ struct EMF_HDR
 #define EMR_CREATECOLORSPACEW	122
 
 /*@
-  @ requires buffer_size >= 2;
-  @ requires (buffer_size&1)==0;
-  @ requires \valid_read(buffer+(0..buffer_size-1));
-  @ requires \valid(file_recovery);
   @ requires file_recovery->data_check==&data_check_emf;
-  @ requires file_recovery->calculated_file_size <= PHOTOREC_MAX_FILE_SIZE;
-  @ ensures \result == DC_CONTINUE || \result == DC_STOP || \result == DC_ERROR;
+  @ requires buffer_size >= 2;
+  @ requires valid_data_check_param(buffer, buffer_size, file_recovery);
+  @ ensures  valid_data_check_result(\result, file_recovery);
   @ assigns file_recovery->calculated_file_size;
   @*/
 static data_check_t data_check_emf(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
@@ -367,16 +364,8 @@ static data_check_t data_check_emf(const unsigned char *buffer, const unsigned i
 }
 
 /*@
-  @ requires buffer_size > 0;
-  @ requires \valid_read(buffer+(0..buffer_size-1));
-  @ requires \valid_read(file_recovery);
-  @ requires file_recovery->file_stat==\null || valid_read_string((char*)file_recovery->filename);
-  @ requires \valid(file_recovery_new);
-  @ requires file_recovery_new->blocksize > 0;
-  @ requires separation: \separated(file_recovery, file_recovery_new);
-  @ ensures \result == 0 || \result == 1;
-  @ ensures (\result == 1) ==> (file_recovery_new->file_stat == \null);
-  @ ensures (\result == 1) ==> (file_recovery_new->handle == \null);
+  @ requires valid_header_check_param(buffer, buffer_size, safe_header_only, file_recovery, file_recovery_new);
+  @ ensures  valid_header_check_result(\result, file_recovery_new);
   @ ensures (\result == 1) ==> (file_recovery_new->extension == file_hint_emf.extension);
   @ ensures (\result == 1) ==> (file_recovery_new->time == 0);
   @ ensures (\result == 1) ==> (file_recovery_new->calculated_file_size >= 0x34);
@@ -385,9 +374,6 @@ static data_check_t data_check_emf(const unsigned char *buffer, const unsigned i
   @ ensures (\result == 1) ==> (file_recovery_new->data_check == &data_check_emf);
   @ ensures (\result == 1) ==> (file_recovery_new->file_check == &file_check_size);
   @ ensures (\result == 1) ==> (file_recovery_new->file_rename== \null);
-  @ ensures (\result == 1) ==> (valid_read_string(file_recovery_new->extension));
-  @ ensures (\result == 1) ==>  \separated(file_recovery_new, file_recovery_new->extension);
-  @ ensures  \result!=0 ==> valid_file_recovery(file_recovery_new);
   @ assigns *file_recovery_new;
   @*/
 static int header_check_emf(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new)