diff --git a/include/devil1geo.h b/include/devil1geo.h
index 7b6b3d2..6d08f1e 100644
--- a/include/devil1geo.h
+++ b/include/devil1geo.h
@@ -85,6 +85,9 @@ typedef struct {
 // input: pointer to struct
     void (* const printcoordinate)(struct Coordinate*, unsigned int);
 
+// input: pointer to struct, file data
+    bool (* const getheader)      (struct Header*, const char*);
+
 // input: pointer of pointer to struct, order, file data
 // ** = 'pass by reference' of a pointer to struct
     bool (* const getmeshheader)  (struct MeshHeader**, 
@@ -96,11 +99,11 @@ typedef struct {
                                    unsigned int offset, 
                                    const char * const);
 
-// input: pointer to struct, order, file data
+// input: pointer to struct, order, file data, file size
     bool (* const getmesh)        (struct Mesh*, 
                                    unsigned int i, 
                                    const char*,
-                                   unsigned int filesize);
+                                   unsigned int);
 } fn_devil1geo;
 extern fn_devil1geo const DEVIL1GEO;
 
diff --git a/include/devil1tex.h b/include/devil1tex.h
index 9013b2b..b002a0a 100644
--- a/include/devil1tex.h
+++ b/include/devil1tex.h
@@ -45,6 +45,9 @@ typedef struct {
 // input: pointer to struct
     void (* const printbatchdesc)(struct TextureBatchDescriptor*);
 
+// input: pointer to struct, file data
+    bool (* const getheader)     (struct TexturePack*, const char*);
+
 // input: pointer of pointer to struct, order, file data, file size
 // ** = 'pass by reference' of a pointer to struct
     bool (* const getbatchdesc)  (struct TextureBatchDescriptor**,
diff --git a/src/devil1geo.c b/src/devil1geo.c
index b329072..d62e13b 100644
--- a/src/devil1geo.c
+++ b/src/devil1geo.c
@@ -9,6 +9,7 @@ static void printmeshbatch(struct Batch*);
 
 static void printcoordinate(struct Coordinate*, unsigned int);
 
+static bool getgheader(struct Header*, const char*);
 
 static bool getmeshheader(struct MeshHeader**, unsigned int i, const char * const);
 
@@ -20,6 +21,7 @@ fn_devil1geo const DEVIL1GEO = {printgheader,
                                 printmeshheader,
                                 printmeshbatch,
                                 printcoordinate,
+                                getgheader,
                                 getmeshheader,
                                 getmeshbatch,
                                 getmesh};
@@ -74,6 +76,14 @@ static void printcoordinate(struct Coordinate *p, unsigned int count) {
     }
 }
 
+static bool getgheader(struct Header* h, const char* filedata) {
+    if (filedata == NULL) {
+        return false;
+    }
+    h = (struct Header*)filedata;
+    return true;
+}
+
 static bool getmeshheader(struct MeshHeader **hs,
                    unsigned int i,
                    const char * const filedata) {
diff --git a/src/devil1tex.c b/src/devil1tex.c
index 5b4d8dd..1bbf2e9 100644
--- a/src/devil1tex.c
+++ b/src/devil1tex.c
@@ -8,8 +8,10 @@ static void printtph(struct TexturePack*);
 // Print Texture Batch Descriptor.
 static void printtbd(struct TextureBatchDescriptor*);
 
-// Get Texture Batch Descriptor.
+// Get Texture Pack Header
+static bool getpackheader(struct TexturePack*, const char*);
 
+// Get Texture Batch Descriptor.
 static bool gettexdescriptor(struct TextureBatchDescriptor**,
                       unsigned int,
                       const char *,
@@ -30,6 +32,7 @@ static bool unpacktexbatch(struct Texture*,
 
 fn_devil1tex const DEVIL1TEX = {printtph,
                                 printtbd,
+                                getpackheader,
                                 gettexdescriptor,
                                 gettexbatch,
                                 unpacktexbatch};
@@ -55,6 +58,14 @@ static void printtbd(struct TextureBatchDescriptor *bd) {
     }
 }
 
+static bool getpackheader(struct TexturePack* p, const char *filedata) {
+    if (filedata == NULL) {
+        return false;
+    }
+    p = (struct TexturePack*)filedata;
+    return true;
+}
+
 static bool gettexdescriptor(struct TextureBatchDescriptor **descriptor,
                       unsigned int i,
                       const char *filedata,