NSD

NSD (most likely to stand for Naughty Dog Software Data or Naughty Dog System Data) is a custom file format created by Naughty Dog for use in the Crash games. The root directory of a Crash game CD will have several sub-directories, with names S0, S1, S2, and S3; within these sub-directories are pairs of files with the name S00000**.NSD/.NSF. Each pair corresponds to a specific level in the game, and these files contain the game data for that level. An NSD file is essentially an index for its paired NSF file, but it also contains additional information such as a level descriptor/header and a loading screen descriptor.

Format

Crash 1

Offset	Field	Size	Value
0x0	Entry Hash Table Offsets	4 bytes x 256	*
0x400	Chunk Count	4 bytes	c
0x404	Entry Hash Table Size	4 bytes	s
0x408	Entry containing object type -> executable EID* type	4 bytes	*
0x40C	Compressed chunk offset table size(?)	4 bytes	*
0x410	Unknown	4 bytes	*
0x414	Unknown	4 bytes	*
0x418	Offset of Uncompressed Chunks	4 bytes	*
0x41C	Compressed Chunk Count	4 bytes	*
0x420	Compressed Chunk Offsets	4 bytes x 64	*
0x520	Entry Hash Table	4 bytes x 2 x s	*
0x520 + (8 x s) + 0x0	Level Header Magic Number	4 bytes	0x1
0x520 + (8 x s) + 0x4	Level ID	4 bytes	*
0x520 + (8 x s) + 0x8	Initial Zone EID	4 bytes	*
0x520 + (8 x s) + 0xC	Initial Camera Path (Item Index)	4 bytes	*
0x520 + (8 x s) + 0x10	Unknown	4 bytes	*
0x520 + (8 x s) + 0x14	Object Type -> Executable EID map	4 bytes x 64	*
?	Descriptor for 'loading screen' image	?

* - Only useful in older versions of Crash 1, but is present in all 3 games.

Structure

Crash 1

struct NSD
{
  union
  {
    unsigned long entryhashoffsets[256];
    unsigned long *entryhashbuckets[256];
  }
  unsigned long chunkcount;
  unsigned long entryhashcount;
  unsigned long unk_408;
  unsigned long unk_40C;
  unsigned long unk_410;
  unsigned long unk_414;
  unsigned long uncompressedoffset;
  unsigned long compressedcount;
  unsigned long compressedoffsets[64];
  hashpair      entryhash[entryhashcount];
  struct levelheader
  {
    const unsigned long magic = ?
    unsigned long levelID;
    unsigned long firstzone;
    unsigned long firstcampath;
    unsigned long unknown;
    unsigned long execeidmap[64];
  };
};

Purpose

TBD