IPAK Files: Difference between revisions

Latest revision as of 01:20, 4 July 2015

IPAK's, implemented in Black Ops 2, are basically an archive of compressed image data.

Structure

struct IPakHeader
{
  unsigned int magic;
  unsigned int version;
  unsigned int size;
  unsigned int sectionCount;
};
 
struct IPakSection
{
  unsigned int type; //enum 0x1 = info, 0x2 = data
  unsigned int offset;
  unsigned int size;
  unsigned int itemCount;
};
 
struct IPakIndexEntry
{
  unsigned __int64 key;
  unsigned int offset;
  unsigned int size;
};
 
struct IPakDataChunkHeader
{
  unsigned int countAndOffset; // 24 bits = offset, 8 bits = count
  unsigned int commands[31]; //(depending on endian) blockSize = (info & 0xFFFF); , compressedFlag = info >> 24;
};

Decompression Methods

The compression method is just the basic LZO1X compression.

PC:

http://pastebin.com/vd9t2U2B

PS3:

1.00 t6mp_ps3f.self - 0x6AEA78

XBOX:

tu9 default_mp.xex - 0x828E5090
tu13 default_mp.xex - 0x828E6308

@@ Line 4: / Line 4: @@
 == Structure ==
-Thanks to kokole for the structure.
+<syntaxhighlight lang="cpp">
- struct ipak_header_t
+struct IPakHeader
- {
+{
- 	char identifier[4]; // "IPAK"
+  unsigned int magic;
- 	unsigned int version; //0x50000
+  unsigned int version;
- 	unsigned int fileSize;
+  unsigned int size;
- 	unsigned int sectionCount; //from what I've seen it's always 2 (1 = info 2 = data)
+  unsigned int sectionCount;
- };
+};
- struct section_t
+struct IPakSection
- {
+{
- 	unsigned int sectionIndex; //enum 0x1 = info, 0x2 = data
+  unsigned int type; //enum 0x1 = info, 0x2 = data
- 	unsigned int sectionStart;
+  unsigned int offset;
- 	unsigned int sectionLength;
+  unsigned int size;
- 	unsigned int numOfEntries; // each entry is a compressed iwi file in section 2 and entry info in section 1
+  unsigned int itemCount;
- };
+};
- struct entry_info_t
+struct IPakIndexEntry
- {
+{
- 	u32 hash; // checksum, type?
+  unsigned __int64 key;
- 	u32 id;
+  unsigned int offset;
- 	u32 entryStart; // location of compressed iwi file
+  unsigned int size;
- 	u32 entryLength;
+};
- }; // 16 bytes
- struct entry_t
+struct IPakDataChunkHeader
- {
+{
- 	entry_header_t header;
+  unsigned int countAndOffset; // 24 bits = offset, 8 bits = count
- 	block_info_t blocks[31]; //they can be null, actual number of blocks is header->blockCount;
+  unsigned int commands[31]; //(depending on endian) blockSize = (info & 0xFFFF); , compressedFlag = info >> 24;
- };
+};
+</syntaxhighlight>
- struct entry_header_t
- {
- 	int blockCount; // actual blockcount = *(byte*)&blockCount[0];
- };
- struct block_info_t
- {			//enum 0x0 = plaintext, 0x1 = encrypted
- 	unsigned int info; //(depending on endian) blockSize = (info & 0xFFFF); , compressedFlag = info >> 24;
- }; // 4 bytes
 == Decompression Methods ==
 The compression method is just the basic LZO1X compression.
-The same as compression used on the SAVEGAME.SVG file for the save data.
 PC: