formats

ARC Format

Archive structure notes for Silent Hill 3 ARC containers.

Silent Hill 3 uses a simple archive format for storing grouped file data in .arc files.

The actual archive data and the filename metadata are split across two different formats:

  • *.arc — the raw file container
  • arc.arc — index file that maps archive entries to real filenames

A normal SH3 archive like pic.arc, msg.arc, or bgam.arc contains:

  • a fixed-size header
  • a fixed-size entry table
  • a padding region
  • raw file data blobs

Endianness

All fields are little-endian.

Header

The archive begins with a 16-byte header:

OffsetTypeNameDescription
0x00u32magicArchive magic, always 0x20030507
0x04u32fileCountNumber of entries in the archive
0x08u32paddingSizeSize of the padding region after the entry table
0x0Cu32field_0CUnknown / usually 0