GPD

GPD (Gamer Profile Data) files are used by the Xbox 360 to store information inside a profile. They are based on the XDBF format. Profiles are composed of many of these files, each named under their respective executable's title id (e.g. 4D5307E6.gpd for Halo 3). The dashboard GPD (FFFE07D1.gpd) contains information and sync information about the titles.

Entry Table

An ID of 0x100000000 indicates that the entry is a Sync List, an ID of 0x200000000 means its a Sync Data entry.

The Settings, Achievement and Title namespaces each have their own Sync List and Sync Data entries.

An ID of 0x8000 usually indicates that entry is information to do with the title (image/name).

Entry Namespaces

Value	Description
1	Achievement
2	Image
3	Setting
4	Title
5	String
6	Achievement Security (created by GFWL for offline unlocked achievements?)
6	Avatar Award (360 only, this is only stored with in the PEC version of the GPD)

Entry IDs

Title Entrys have the ID of there corresponding TitleID.

Value	Description
1676148804	AvatarSetting(stores avatar clothing and colours)
1080295439	GamerPicKey(string defining the users GamerPic)
32768	TitleInfo(such as Title Image or Title Name)
8589934592	SyncData(http://free60.org/GPD#Sync_Data)
4294967296	SyncList(http://free60.org/GPD#Sync_Lists)

Entry Structures

Achievement Entries

Offset	Length	Type	Information
0x0	0x4	unsigned int	Struct size (0x1C)
0x4	0x4	unsigned int	Achievement ID
0x8	0x4	unsigned int	Image ID
0xC	0x4	signed int	Gamerscore
0x10	0x4	unsigned int	Flags (see below)
0x14	0x8	signed long	Unlock Time
0x18	null terminated	unicode string	Name
0x18 + Name length	null terminated	unicode string	Locked Description
0x18 + Name length + Locked Description length	null terminated	unicode string	Unlocked Description

Setting Entries

Offset	Length	Type	Information
0	4	Int32	SettingID(entry ID)
4	4	Int32	Null/unused
8	1	Byte	DataType (see Below)
9	7	Byte[]	Unknown
16	*depends on DataType*	*depends on DataType*	Data

DataType
Context
Int32
Int64
Double
String
Float
Binary
DateTime

Reading the SettingEntry might be a little tricky, depending on the DataType. Gonna write down later how to.

Image Entries

Image entries are composed of a PNG image.
To Read and write this its probable best to use memory streams, I do it like

       public byte[] Data
       {
           get
           {
               byte[] TempData;
               System.IO.MemoryStream TempStream = new System.IO.MemoryStream();
               Img.Save(TempStream, System.Drawing.Imaging.ImageFormat.Png);
               TempData = TempStream.ToArray();
               TempStream.Close();
               return TempData;
           }
           set
           {
               System.IO.MemoryStream TempStream = new System.IO.MemoryStream(value);
               Img = System.Drawing.Image.FromStream(TempStream);
               TempStream.Close();
           }

Title Entries

These entries are located in the FFFE07D1.gpd. To get to them, the id for the XDBF entry is the title ID of the game, and the XDBF entry type is String. For more information about XDBF go to http://www.free60.org/XDBF

Offset	Length	Type	Information
0x0	0x4	unsigned int	Title ID
0x4	0x4	signed int	Achievement Count
0x8	0x4	signed int	Achievement Unlocked Count
0xC	0x4	signed int	Gamerscore Total
0x10	0x4	signed int	Gamerscore Unlocked
0x14	0x2	short	Unknown
0x16	0x01	byte	Avatar Assets Earned
0x17	0x01	byte	Avatar Assets Max
0x18	0x01	byte	Male Avatar Assets Earned
0x19	0x01	byte	Male Avatar Assets Max
0x1A	0x01	byte	Female Avatar Assets Earned
0x1B	0x01	byte	Female Avatar Assets Max
0x1C	0x4	signed int	Unknown/Reserved
0x20	0x8	signed long	Last Played Time
0x28	null terminated	unicode string	Title Name

Avatar Award Entries

The entries are only supported within the PEC version of the GPD. The images for the avatar awards however, are stored in the game GPD for that game.

Offset	Length	Type	Information
0	4	uint32	Struct size (0x2C)
4	4	UInt32	Award ID
8	2	UInt16	Unknown
10	2	UInt16	GenderFlag
12	4	UInt32	Unknown
16	4	UInt32	GameID
20	4	UInt32	Image ID
24	4	uInt32	Flags(Same as achievement?)
28	8	Int64	Unlock Time
36	4	u/Int32	Unknown
40	4	u/Int32	Unknown
44	Till Null	UniCode	Name
44 + Name length	Till Null	UniCode	Locked Description
44 + Name length + Locked Description length	Till Null	UniCode	Unlocked Description

String Entries

String entries are simply a unicode string, to the length specified by the entry.

Sync Lists

This is a list of "Sync Items".

You can find the total sync items by,

((SyncList.Length / 16) - 1)

Sync Item

Offset	Length	Type	Information
0	8	Int64	EntryID
8	8	Int64	SyncID

I don't know much about the second id, however I believe it to have something to do with the SyncData's "Next Sync ID".

Sync Data

Offset	Length	Type	Information
0x0	0x8	unsigned long	Next Sync ID
0x8	0x8	unsigned long	Last Synced ID
0x10	0x8	signed long	Last Synced Time